Efficacy of the neurokinin-1 receptor antagonist aprepitant in children with cyclical vomiting syndrome

Definition, investigation and management of gastrointestinal dystonia in children and young people with neurodisability

BACKGROUND

Children and young people with severe neurodisabling conditions (CYPSND)experience severe functional gastrointestinal symptoms and dependence on artificial nutrition. 'Gastrointestinal dystonia' (GID) has been applied by clinicians when symptoms become debilitating and potentially life-limiting. Evidence is lacking regarding the definition and appropriate management of GID.

METHODS

We therefore assembled a RAND appropriateness panel. We performed a systematic review, created an online survey and distributed this to a panel of 27 experts from five stakeholder groups from 13 UK specialist centres across the British Isles (gastroenterology, neurology/neurodisability, surgery, palliative care and allied health professionals). A Disagreement Index ≥1 indicated disagreement.

FINDINGS

The panel rated the appropriateness of 250 statements covering the following in GID: definition, clinical evaluation, nutritional assessment/feeding strategies, investigations, medications and prescribing, surgical interventions, safeguarding, palliative care and ethics. Agreement was reached except in selected statements regarding uncommon diagnostic features. There was uncertainty in specific clinical scenarios regarding: investigation, the use of blenderised diet, certain pharmacological agents and surgical interventions. The only intervention deemed inappropriate was antireflux surgery in the context of GID and gastrointestinal dysmotility without reflux disease. The remaining statements (198) were considered appropriate.

INTERPRETATION

We present a comprehensive review, agreement on the definition of GID and recommendations on management pathways agreed by a selected panel of multidisciplinary experts. Clear diagnostic criteria will enable important epidemiological work to record outcomes for this complex patient group. Identifying the associated morbidity, burden of care and mortality will help advocate for appropriate health resources and support to carers and families.

European Guideline on Chronic Nausea and Vomiting-A UEG and ESNM Consensus for Clinical Management

INTRODUCTION

Chronic nausea and vomiting are symptoms of a wide range of gastrointestinal and non-gastrointestinal conditions. Diagnosis can be challenging and requires a systematic and well-structured approach. If the initial investigation for structural, toxic and metabolic disorders is negative, digestive motility and gut-brain interaction disorders should be assessed. United European Gastroenterology (UEG) and the European Society for Neurogastroenterology and Motility (ESNM) identified the need for an updated, evidence-based clinical guideline for the management of chronic nausea and vomiting.

METHODS

A multidisciplinary team of experts in the field, including European specialists and national societies, participated in the development of the guideline. Relevant questions were addressed through a literature review and statements were developed and voted on according to a Delphi process.

RESULTS

Ninety-eight statements were identified and voted following the Delphi process. Overall agreement was high, although the grade of scientific evidence was low in many areas. Disagreement was more evident for some pharmacological treatment options. A diagnostic algorithm was developed, focussing on the differentiating features between gastrointestinal motility and gut-brain interaction disorders with predominant nausea and vomiting.

CONCLUSION

These guidelines provide an evidence-based framework for the evaluation and treatment of patients with chronic nausea and vomiting.

Treatment principles in adults and development of patient-reported outcomes in cyclic vomiting syndrome

BACKGROUND

Cyclic vomiting syndrome is a chronic disorder of gut-brain interaction that is present in both adults and children. It is characterized by severe nausea, vomiting, abdominal pain, and several non-GI symptoms. It is also associated with several comorbid conditions such as anxiety and depression, which affect overall health care outcomes.

METHODS

This article delineates treatment principles, encompassing both abortive interventions and prophylactic regimens currently recommended for CVS. However, it underscores a critical concern: the absence of FDA-approved medications for CVS treatment, with existing therapies relying on retrospective and open-labeled trials.

KEY RESULTS

This article emphasizes the pressing need for the development of CVS-specific outcome assessment tools to facilitate more accurate evaluation and robust data collection for the future studies. In exploring this deficiency, the manuscript also presents the up-to-date data and development that enhances our comprehension of patient-centric concepts, and the challenges faced in creating CVS-specific tools, and presents a roadmap for their development. Addressing this gap is crucial for advancing our understanding of CVS and optimizing patient care.

CONCLUSIONS AND INFERENCES

This elucidates the current state of CVS management but also advocates for a future where tailored tools enhance our ability to measure and improve the outcomes for individuals with this debilitating disorder.

Acute care of cyclic vomiting syndrome and cannabinoid hyperemesis syndrome in the home and emergency department

BACKGROUND

Cyclic vomiting syndrome (CVS) and cannabinoid hyperemesis syndrome (CHS) are both characterized by episodic, acute transitions from asymptomatic states to highly symptomatic states of nausea, repetitive vomiting, and often severe abdominal pain. Patients with CVS and CHS face significant challenges to abort or mitigate episodes at home and often require emergency department (ED)-based care.

PURPOSE

This paper reviews the current treatment approach to abort acute CVS and CHS episodes at home and in ED settings. Multiple pharmacologic and nonpharmacologic interventions have been demonstrated to potentially abort CVS or CHS episodes. Systemic pharmacologic agents often used as abortive therapy include triptans, antiemetics, anxiolytics, NK-1 receptor antagonists, antipsychotics, sedatives in general, and various analgesic / anti-inflammatory medications. Nonsystemic, nonpharmacologic approaches include reducing external stimuli (quiet room, dim lights, etc.), and hot water bathing or the application of topical capsaicin cream. More research is needed to develop evidence-based, individualized abortive treatment plans, as well as to determine whether the abortive treatment for CVS requires a fundamentally different approach than for CHS. When home-based approaches fail, all patients with CVS or CHS should receive nonjudgmental, informed, and compassionate care in the ED to abort their episode. Patients with more severe forms of CVS/CHS who require more frequent ED utilization should develop care plans with their ED to assure predictable and effective treatment.

Endocannabinoid signaling in stress, nausea, and vomiting

BACKGROUND

Classical antiemetics that target the serotonin system may not be effective in treating certain nausea and vomiting conditions like cyclic vomiting syndrome (CVS) and cannabinoid hyperemesis syndrome (CHS). As a result, there is a need for better therapies to manage the symptoms of these disorders, including nausea, vomiting, and anxiety. Cannabis is often used for its purported antiemetic and anxiolytic effects, given regulation of these processes by the endocannabinoid system (ECS). However, there is considerable evidence that cannabinoids can also produce nausea and vomiting and increase anxiety in certain instances, especially at higher doses. This paradoxical effect of cannabinoids on nausea, vomiting, and anxiety may be due to the dysregulation of the ECS, altering how it maintains these processes and contributing to the pathophysiology of CVS or CHS.

PURPOSE

The purpose of this review is to highlight the involvement of the ECS in the regulation of stress, nausea, and vomiting. We discuss how prolonged cannabis use, such as in the case of CHS or heightened stress, can dysregulate the ECS and affect its modulation of these functions. The review also examines the evidence for the roles of ECS and stress systems' dysfunction in CVS and CHS to better understand the underlying mechanisms of these conditions.

Mitigating the Risk of QTc Prolongation When Using Haloperidol for Acute Treatment of Cannabinoid Hyperemesis Syndrome in Adolescents and Young Adults

Background/Objectives: Cannabinoid Hyperemesis Syndrome (CHS), associated with long-term cannabinoid use, has been increasingly observed in emergency room visits as more states in the U.S. have legislatively permitted medical and recreational marijuana use. The acute management of CHS primarily focuses on antiemetic treatment and supportive care. However, both the condition itself and the antiemetic drugs, such as haloperidol, may cause QTc prolongation. Methods: We reported two adolescent cases admitted to the emergency department for acute antiemesis management of CHS who received haloperidol treatment. A literature review was performed through October 2024 for previously published cases of QTc prolongation and/or Torsades de Pointes (TdP) in adolescents and young adults. Results: A 15-year-old female presented with hypokalemia and hypomagnesemia upon admission. She complained of chest pain and tachycardia, and the electrocardiogram (EKG) showed prolonged QTc (528 msec). The haloperidol infusion was discontinued. She recovered well post-discharge without complaints. A 17-year-old female had a borderline prolonged QT interval (476 msec). Her nausea and vomiting improved with a three-dose course of intravenous fosaprepitant before discharge. Our literature search identified five severe cases with life-threatening episodes of QTc prolongation and/or TdP in adolescents and young adults. Conclusions: Patients with CHS are at higher risk of QTc prolongation due to cannabis use, electrolyte imbalance, and antiemetic medications. We recommend vigilant EKG monitoring, particularly before initiating and throughout haloperidol treatment. If the patient presents with an increased risk of QTc prolongation, consider using topical capsaicin, lorazepam, aprepitant/fosaprepitant, and olanzapine as alternatives.

Utility of Aprepitant in the Management of Pediatric Patients with Cyclical Vomiting Syndrome

Introduction: Cyclical vomiting syndrome (CVS) is a recurrent debilitating illness characterized by intense episodes of nausea and emesis with widely varied pharmacological management across the country. Aprepitant is now increasingly used in patients with CVS. The impact of aprepitant as an abortive therapy in the readmission of pediatric patients with CVS is currently unknown. Methodology: We analyzed all pediatric patients with a primary diagnosis of CVS using the ICD-10 code in the Pediatric Health Information System database of the Children's Hospital Association. We evaluated the demographic data, comorbid conditions, and management details during the inpatient stay. CVS patients who received aprepitant during their inpatient hospitalization were compared with patients without aprepitant use. Seven-day readmission rate for CVS was used as the outcome variable to assess the effectiveness of the aprepitant in aborting an episode. Propensity score matching was used to match the two cohorts. Results: We analyzed 1775 patients of which 96 received aprepitant during the inpatient hospitalization. The aprepitant group had a more severe hospitalization course as evidenced by an increased duration of hospital stay (5 vs. 3 days) and total hospitalization costs ($11,790 vs. $6380). There were no significant differences in the 7-day (17% vs. 16%, p = 0.91) readmission rate and results were not altered by propensity score matching. Conclusions: Aprepitant use as an abortive therapy did not affect the 7-day CVS-related readmission rate. Further prospective studies are needed to explore the role of aprepitant as an abortive agent in the management of CVS in the pediatric population.

A Comprehensive Review and Update on Cannabis Hyperemesis Syndrome

Cannabis, derived from Cannabis sativa plants, is a prevalent illicit substance in the United States, containing over 400 chemicals, including 100 cannabinoids, each affecting the body's organs differently upon ingestion. Cannabis hyperemesis syndrome (CHS) is a gut-brain axis disorder characterized by recurring nausea and vomiting intensified by excessive cannabis consumption. CHS often goes undiagnosed due to inconsistent criteria, subjective symptoms, and similarity to cyclical vomiting syndrome (CVS). Understanding the endocannabinoid system (ECS) and its dual response (pro-emetic at higher doses and anti-emetic at lower doses) is crucial in the pathophysiology of CHS. Recent research noted that type 1 cannabinoid receptors in the intestinal nerve plexus exhibit an inhibitory effect on gastrointestinal motility. At the same time, the thermoregulatory function of endocannabinoids might explain compulsive hot bathing in CHS patients. The prevalence of cannabis CHS is expected to rise as legal restrictions on its recreational use decrease in several states. Education and awareness are vital in diagnosing and treating CHS as its prevalence increases. This comprehensive review explores the ECS's involvement, CHS management approaches, and knowledge gaps to enhance understanding of this syndrome.

Cyclic vomiting syndrome: From pathophysiology to treatment

Cyclic vomiting syndrome (CVS) is a disorder characterized by recurrent and unpredictable episodes of intense vomiting, interspersed with periods of apparent wellbeing. This disorder, which primarily affects children and adolescents but can persist into adulthood, has recently been the subject of extensive study and analysis in the medical literature. The aim of the present review is to examine the most important aspects of the epidemiology, pathophysiology, subtypes, diagnostic criteria, and current management of CVS. Even though the exact etiology remains unknown, genetic factors (polymorphisms), nervous system alterations and autonomic dysregulation, and environmental factors (use and abuse of cannabinoids) are postulated as possible triggers. CVS has significant diagnostic challenges, given that there is no specific test for confirming its presence. Thorough evaluation of symptoms and the ruling out of other possible causes of recurrent vomiting are required. Management of CVS typically involves a multidisciplinary approach. Pharmacologic options are explored, such as antiemetics and preventive medications, as well as behavioral and psychologic support therapies. Treatment personalization is essential, adapting it to the individual needs of each patient. Despite advances in the understanding of CVS, it remains a significant clinical challenge. This disorder impacts the quality of life of those affected and their families, underscoring the ongoing need for research and the development of more effective treatment strategies.

Perspectives, experiences, and concerns with cyclical vomiting syndrome: Insights from online targeted-disease forums

INTRODUCTION

There is limited research examining the biopsychosocial impact of cyclic vomiting syndrome (CVS) on patients. This study aims to assess individuals' experiences, fears, and concerns associated with CVS and the impact of CVS on their daily lives.

METHODS

We employed social netnography to analyze publicly available posts related to CVS that were identified from six US online forums and Twitter. A randomly selected sub-cohort of posts per pre-defined criteria was first qualitatively analyzed using an inductive thematic approach. Then, machine learning topic modeling was applied to explore themes in an unsupervised manner for the entire corpus of posts. Afterward, findings from the qualitative and quantitative approaches were integrated to generate a thematic network.

RESULTS

Based on the 39,179 collected posts, seven domain themes were identified. Overall, 41.4% of the posts were related to "biopsychosocial burden" of CVS, including physical impact, psychological impact, and social impact. In 22.3% of posts, individuals shared their experience of "interactions with the healthcare system", and 14.2% of posts were related to "perceived CVS triggers." Individuals also shared "solutions to alleviate their symptoms" and "mental health needs" in 10.2% and 8.8% of posts, respectively. Finally, 6.1% of the posts were about "seeking/sharing support" with others.

DISCUSSION

This is the first social netnography study to describe the in-depth experiences of individuals living with CVS and the marked impact on their physical, mental, and social health. The study also highlights the unmet need for effective therapies, both pharmacological and non-pharmacological, to alleviate the biopsychosocial impact of CVS.

Cannabinoid hyperemesis syndrome: prevalence and management in an era of cannabis legalization

As more states legalize cannabinoid products for recreational use and medicinal purposes, the prevalence of cannabinoid hyperemesis syndrome has become increasingly common. Yet, it remains unrecognized to many healthcare providers along with the most efficacious treatments. Cannabinoid hyperemesis syndrome most often presents with episodic vomiting secondary to chronic daily cannabis use over several months to years. Patients often complain of nausea and abdominal pain that is improved by taking hot showers or baths. Symptoms are alleviated with the cessation of cannabis use over a period of 6-12 months. Treatment for acute attacks often consists of parenteral benzodiazepines in the inpatient setting. Long-term management and prevention of further attacks are aided by tricyclic antidepressants such as amitriptyline with a dose range of 50-200 mg/d. Once a patient is in remission, amitriptyline can be tapered slowly. As cannabis becomes more widely available and accepted in the continental United States, so must education on the diagnosis of cannabinoid hyperemesis syndrome and treatment strategies.

Cannabinoids and the Gastrointestinal Tract

The synthesis and degradation of endocannabinoids, location of cannabinoid (CB) receptors, and cannabinoid mechanisms of action on immune/inflammatory, neuromuscular, and sensory functions in digestive organs are well documented. CB2 mechanisms are particularly relevant in immune and sensory functions. Increasing use of cannabinoids in the United States is impacted by social determinants of health including racial discrimination, which is associated with tobacco and cannabis co-use, and combined use disorders. Several conditions associated with emesis are related to cannabinoid use, including cannabinoid hyperemesis or withdrawal, cyclic vomiting syndrome, and nausea and vomiting of pregnancy. Cannabinoids generally inhibit gastrointestinal motor function; yet they relieve symptoms in patients with gastroparesis and diverse nausea syndromes. Cannabinoid effects on inflammatory mechanisms have shown promise in relatively small placebo-controlled studies in reducing disease activity and abdominal pain in patients with inflammatory bowel disease. Cannabinoids have been studied in disorders of motility, pain, and disorders of gut-brain interaction. The CB2-receptor agonist, cannabidiol, reduced the total Gastroparesis Cardinal Symptom Index and increases the ability to tolerate a meal in patients with gastroparesis appraised over 4 weeks of treatment. In contrast, predominant-pain end points in functional dyspepsia with normal gastric emptying were not improved significantly with cannabidiol. The CB2 agonist, olorinab, reduced abdominal pain in inflammatory bowel disease in an open-label trial and in constipation-predominant irritable bowel syndrome in a placebo-controlled trial. Cannabinoid mechanisms alter inflammation in pancreatic and liver diseases. In conclusion, cannabinoids, particularly agents affecting CB2 mechanisms, have potential for inflammatory, gastroparesis, and pain disorders; however, the trials require replication and further understanding of risk-benefit to enhance use of cannabinoids in gastrointestinal diseases.

Recent advances in the treatment of gastrointestinal motility disorders in children

INTRODUCTION

Pediatric gastrointestinal motility disorders represent some of the most challenging clinical conditions with largely undefined pathogenetic pathways and therefore limited therapeutic options. Herein, we provide an overview of the recent advances in treatment options for these disorders and their clinical impact.

AREAS COVERED

PubMed and Medline databases were searched for relevant articles related to the treatment of achalasia, esophageal atresia, gastroparesis, PIPO and constipation published between 2017 and 2022. In this article, we review and summarize recent advances in management of gastrointestinal motility disorders in children with a particular focus on emerging therapies as well as novel diagnostic modalities that help guide their application or develop new, more targeted treatments.

EXPERT OPINION

Gastrointestinal motility disorders represent one of the most challenging conundrums in pediatric age and despite significant advances in investigative tools, the palette of treatment options remain limited. Overall, while pharmacological options have failed to bring a curative solution, recent advances in minimal invasive therapeutic and diagnostic techniques have emerged as potential keys to symptom and quality of life improvement, such as ENDOFLIP, POEM, cine-MRI, fecal microbiota transplantation.

An assessment of the effects of neurokinin1 receptor antagonism against nausea and vomiting: Relative efficacy, sites of action and lessons for future drug development

A broad-spectrum anti-vomiting effect of neurokinin1 receptor antagonists (NK1 RA), shown in pre-clinical animal studies, has been supported by a more limited range of clinical studies in different indications. However, this review suggests that compared with vomiting, the self-reported sensation of nausea is less affected or possibly unaffected (depending on the stimulus) by NK1 receptor antagonism, a common finding for anti-emetics. The stimulus-independent effects of NK1 RAs against vomiting are explicable by actions within the central pattern generator (ventral brainstem) and the nucleus tractus solitarius (NTS; dorsal brainstem), with additional effects on vagal afferent activity for certain stimuli (e.g., highly emetogenic chemotherapy). The central pattern generator and NTS neurones are multifunctional so the notable lack of obvious effects of NK1 RAs on other reflexes mediated by the same neurones suggests that their anti-vomiting action is dependent on the activation state of the pathway leading to vomiting. Nausea requires activation of cerebral pathways by projection of information from the NTS. Although NK1 receptors are present in cerebral nuclei implicated in nausea, and imaging studies show very high receptor occupancy at clinically used doses, the variable or limited ability of NK1 RAs to inhibit nausea emphasizes: (i) our inadequate understanding of the mechanisms of nausea; and (ii) that classification of a drug as an anti-emetic may give a false impression of efficacy against nausea vs. vomiting. We discuss the potential mechanisms for the differential efficacy of NK1 RA and the implications for future development of drugs that can effectively treat nausea, an area of unmet clinical need.

Efficacy of aprepitant as a prophylactic medication in adults with cyclic vomiting syndrome

BACKGROUND

Aprepitant is a neurokinin-1 receptor antagonist, and recent guidelines by the American Neurogastoenterology and Motility Society recommend its use as prophylaxis in moderate-to severe cyclic vomiting syndrome (CVS). Data are limited to small studies in children. We aimed to determine its efficacy in adults with CVS.

METHODS

A retrospective review of CVS patients diagnosed using Rome criteria at a tertiary referral center was conducted. Drug response was defined as >50% reduction in symptoms and/or healthcare utilization. An intent-to-treat (ITT) analysis was conducted.

KEY RESULTS

Of 96 patients prescribed aprepitant, 26 (27%) were unable to start due to cost/lack of insurance coverage. Of 70 receiving therapy, mean age was 33 ± 11 years; 51 (73%) were female and 56 (80%) Caucasian. The majority (93%) were refractory to other prophylactic medications. Aprepitant was taken thrice weekly in 51 (73%), daily in 16 (23%) and a few times a month in 3 (4%) due to cost. Fifty (71.4%) had a global symptom response to aprepitant. There was significant reduction in the number of CVS episodes (14.5 ± 11.7 to 6.2 ± 8.0, p < 0.0001), emergency department visits (4.2 ± 7.7 to 1.8 ± 3.4, p = 0.006), and hospital admissions (1.6 ± 3.9 to 0.8 ± 2.1, p = 0.02) in patients treated with aprepitant. Seven (10%) discontinued the drug due to minor side effects.

CONCLUSIONS AND INFERENCES

Aprepitant is a safe and effective prophylactic medication in adults with refractory CVS. Adequate insurance coverage is a major barrier preventing its use.

Clinical characteristics and long-term outcomes in patients with cyclic vomiting syndrome: A 15-year experience at a tertiary referral center

BACKGROUND

Cyclic vomiting syndrome (CVS) is a disorder of gut-brain interaction (DGBI) characterized by recurrent episodes of nausea and vomiting. Most children outgrow their CVS symptoms and develop migraine headaches, but there are limited data in adults. We thus sought to determine the natural history of CVS in adults.

METHODS

We conducted a retrospective analysis of patients at a specialized tertiary care clinic. Frequency of CVS episodes, emergency department (ED) visits, and hospitalizations were recorded at the index visit and at follow-up.

KEY RESULTS

Of 455 CVS patients with complete data, mean age was 33 ± 13 years, 294 (65%) were female, and 392 (86%) were Caucasian. Mean duration of follow-up was 47.4 ± 37.2 months. There was a significant reduction in frequency of CVS episodes/year (18 to 6.8), ED visits (6.1 to 2), and hospitalizations (2.3 to 0.7) (all p-values < 0.001) but only 88 (19%) of patients had complete resolution of episodes at follow-up. On multivariable regression analysis, non-white race [0.33 (0.11-0.98) p = 0.01], comorbidity count [0.77 (0.62-0.95) p = 0.01], cannabis use [0.36 (0.2-0.65) p = 0.0007], and aprepitant use [0.2 (0.08-0.005) p < 0.001] were associated with a reduced odds of complete resolution of CVS episodes. Of note, 19 patients (4%) died.

CONCLUSIONS AND INFERENCES

While most adults with CVS improved with specialized care, in contrast to children, only a small subset (~1 in 5) had complete resolution of symptoms. Reasons for the effects of race, cannabis use, and comorbidity burden on outcomes in CVS are unclear and warrant further investigation.

Diagnosis and Management of Cyclic Vomiting Syndrome: A Critical Review

Cyclic vomiting syndrome (CVS) is a chronic disorder of gut-brain interaction characterized by recurrent disabling episodes of nausea, vomiting, and abdominal pain. CVS affects both children and adults with a prevalence of approximately 2% in the United States. CVS is more common in female individuals and affects all races. The pathophysiology of CVS is unknown and a combination of genetic, environmental, autonomic, and neurohormonal factors is believed to play a role. CVS is also closely associated with migraine headaches and likely have a shared pathophysiology. The diagnosis of CVS is based on the Rome criteria, and minimal recommended testing includes an upper endoscopy and imaging studies of the abdomen. CVS is frequently associated with anxiety, depression, and autonomic dysfunction. Patients with CVS commonly use cannabis therapeutically for symptom relief. By contrast, cannabinoid hyperemesis syndrome is believed to be a subset of CVS with chronic heavy cannabis use leading to hyperemesis. Due to the recalcitrant nature of the illness, patients often visit the emergency department and are hospitalized for acute CVS flares. Guidelines on the management of CVS recommend a biopsychosocial approach. Prophylactic therapy consists of tricyclic antidepressants (amitriptyline), antiepileptics (topiramate), and aprepitant in refractory patients. Abortive therapy consists of triptans, antiemetics (ondansetron), and sedation. Treatment of comorbid conditions is extremely important to improve overall patient outcomes. CVS has a significant negative impact on patients, families, and the healthcare system, and future research to understand its pathophysiology and develop targeted therapies is needed.

Abdominal migraine and cyclical vomiting syndrome

Abdominal migraine and cyclical vomiting syndrome (CVS) are characteristic syndromes which have overlapping characteristics with migraine but lack the cardinal symptom of headache. Both abdominal migraine and CVS are characterized by recurrent attacks of nausea, vomiting, and/or abdominal pain lasting hours to a few days, with symptom freedom between attacks. Both abdominal migraine and CVS typically occur in children and adolescents, who often go on to develop more typical migraine headaches when older, but may also present for the first time in adults. Due to their shared characteristics and association with migraine headaches, abdominal migraine and CVS are sometimes called "migraine equivalents," and their pathophysiology is assumed to overlap with migraine headache. This chapter describes what is known about the clinical characteristics, epidemiology, pathophysiology, and prognosis of abdominal migraine and CVS, and explores their relationship to migraine. We also review the existing evidence for the nonpharmacological management, acute treatment of attacks, and preventive treatments for both abdominal migraine and CVS.

Current understanding of the etiology of cyclic vomiting syndrome and therapeutic strategies in its management

INTRODUCTION

Cyclic vomiting syndrome is a chronic debilitating disorder of the gut-brain interaction and is characterized by recurrent episodes of nausea and vomiting.Recent studies indicate that it is common and affects 2% of the US population. Unfortunately, there is significant heterogeneity in the management of these patients in the medical community. This review article aims to bridge this gap and will review the epidemiology and etiology with a focus on management of CVS.

AREAS COVERED

This article reviews the epidemiology, and pathophysiology of CVS and impact on patients. It also discusses management based on recent guidelines based on which is intended for the busy clinician. A literature search was done using PubMed and key words "cyclic vomiting", "management", "etiology", and pathophysiology were used to identify articles of importance.

EXPERT OPINION

CVS is a complex, poorly understood disorder of gut-brain interaction (DGBI) and has a significant negative impact on patients, families and the healthcare system. Recent guidelines recommend a multidisciplinary approach to management using prophylactic therapy in moderate-severe CVS and abortive medication for acute flares. However more research is needed to better understand the pathophysiology and develop targeted therapies for CVS.

Cyclic Vomiting Syndrome in Pediatric Patients: A Review of Therapeutics

Cyclic vomiting syndrome (CVS) is a functional gastrointestinal disorder that can present quite a challenge to clinicians caring for children with this complex disease. Different therapeutic interventions are recommended for prophylaxis and acute abortive therapy for a CVS attack. The aim of this review is to summarize therapeutic treatment recommendations from the 2008 North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition (NASPGHN) Consensus Statement on the Diagnosis and Management of Cyclic Vomiting Syndrome and discuss studies contemporary to this expert recommendation. After an extensive search of medical databases, 8 studies that evaluated therapeutic treatments for CVS were identified. Amitriptyline and cyproheptadine remain the standard of care for prophylaxis. Nutritional supplements such as carnitine and coenzyme Q10 have shown efficacy in decreasing episodes and severity in small studies with high tolerability among patients. The combination of ondansetron and sumatriptan are recommended for abortion of an acute vomiting episode, but other agents such as aprepitant and sedative agents can be considered when vomiting is refractory to initial treatments.

Long-Term Daily Administration of Aprepitant for the Management of Intractable Nausea and Vomiting in Children With Life-Limiting Conditions: A Case Series

BACKGROUND

Nausea and vomiting is a common symptom in children through their end of life journey. Aprepitant, a NK-1 antagonist, has become a potent weapon in the fight against chemo-induced nausea and vomiting. However, its use in palliative care for refractory nausea and vomiting has been limited due to limited experience or evidence of continuous use. Emerging evidence suggests that continuous use is not only safe, but also effective in patients with nausea and vomiting refractory to multiple lines of antiemetic therapy.

METHODS

We conducted a single centre retrospective chart review of children receiving care from a specialist palliative care team who were given continuous daily aprepitant for nausea and vomiting and were unresponsive to at least two prior lines of antiemetic therapy. Parental reports of the impact of nausea on mobility and feeding were used as proxy efficacy markers. Duration of effect and toxicity was also evaluated.

RESULTS

Ten children (eight with cancer as a primary diagnosis and two with noncancer diagnoses) received continuous aprepitant and all showed resolution of nausea and vomiting and an increased ability to mobilize and tolerate feeds. No adverse events noted.

CONCLUSION

Our review suggests a role for aprepitant in management of refractory nausea and vomiting, demonstrating safety and efficacy. This case series is the first report of aprepitant use in this manner in the paediatric palliative care setting.

Pharmacology, Clinical Effects, and Therapeutic Potential of Cannabinoids for Gastrointestinal and Liver Diseases

Cannabis and cannabinoids (such as tetrahydrocannabinol and cannabidiol) are frequently used to relieve gastrointestinal symptoms. Cannabinoids have effects on the immune system and inflammatory responses, as well as neuromuscular and sensory functions of digestive organs, including pancreas and liver. Cannabinoids can cause hyperemesis and cyclic vomiting syndrome, but they might also be used to reduce gastrointestinal, pancreatic, or hepatic inflammation, as well as to treat motility, pain, and functional disorders. Cannabinoids activate cannabinoid receptors, which inhibit release of transmitters from presynaptic neurons and also inhibit diacylglycerol lipase alpha, to prevent synthesis of the endocannabinoid 2-arachidonoyl glycerol. However, randomized trials are needed to clarify their effects in patients; these compounds can have adverse effects on the central nervous system (such as somnolence and psychosis) or the developing fetus, when used for nausea and vomiting during pregnancy. Cannabinoid-based therapies can also hide symptoms and disease processes, such as in patients with inflammatory bowel diseases. It is important for gastroenterologists and hepatologists to understand cannabinoid mechanisms, effects, and risks.

Management of Pediatric Cannabinoid Hyperemesis Syndrome: A Review

With significant increases noted in adolescent marijuana use across the United States, perhaps as a result of legislative changes over the past half-decade, clinicians must be increasingly aware of the potential negative health effects. One such effect that warrants concern is cannabinoid hyperemesis syndrome (CHS) in the pediatric population. A systematic review of the literature was performed to determine the safety and efficacy of management strategies for CHS using PubMed, Scopus, the Cumulative Index of Nursing and Allied Health (CINAHL), Web of Science, and Cochrane Library databases. Search terms used in each database were "pediatric OR child OR children OR adolescent" AND "cannabinoid OR marijuana" AND "hyperemesis OR cyclic vomiting OR vomiting" NOT "seizure OR chemotherapy OR pregnancy OR cancer OR AIDS OR HIV." Fourteen pieces of literature that described either effective, ineffective, or supportive management strategies for pediatric CHS were included in this review. Benzodiazepines were the most reported efficacious agents, followed by topical capsaicin cream and haloperidol. A total of 9 of the 14 studies described intravenous fluid resuscitation and hot bathing rituals as supportive measures, and 7 cases reported traditional antiemetics were ineffective for CHS. The heterogenicity of reported data, combined with the limited number of encounters, make it difficult to ascertain whether a definitive treatment strategy exists. Clinicians should be cognizant of pharmacotherapy agents that are efficacious, and perhaps more importantly, avoid using traditional antiemetic therapies that do not provide benefit.

Highly effective use of aprepitant in an adolescent girl with severe cyclic vomiting syndrome

Cyclic vomiting syndrome (CVS) is a debilitating functional gastrointestinal disorder. Diagnosis is based on the Rome III criteria. There are no evidence-based guidelines for the management of paediatric CVS, although ondansetron and antimigraine medications are frequently tried. We describe a 13-year-old adolescent girl with severe CVS and numerous hospital admissions for dehydration because of cyclic vomiting. She had failed oral ondansetron therapy. Oral aprepitant (125 mg in the first, and 85 mg on the second and third days), a neurokinin 1 receptor antagonist that has been approved for preventing chemotherapy-induced vomiting or postoperative emesis, was tried in our patient at home during the first prodromal signs of an upset stomach. She had a dramatic response to it, with no further episodes of vomiting since its start. There is an urgent need for randomised clinical studies to assess the efficacy of available treatment options, including aprepitant in patients with severe CVS.

Cyclic vomiting syndrome: A narrative review and guide to management

OBJECTIVES/BACKGROUND

Cyclic vomiting syndrome (CVS) is a disabling disorder of gut-brain interaction manifested by stereotypical and severe episodes of nausea and vomiting. Prevalence data indicate that CVS affects 1-2% of children and there has been a recent dramatic rise in diagnosed adults.

METHODS

This narrative review summarizes relevant literature pertaining to pediatric and adult CVS and provides a guide to management based on extensive clinical experience.

RESULTS

More timely diagnosis is facilitated by an expert consensus diagnostic approach and limited testing. Some diagnostic tests of exclusion remain essential. These include an upper gastrointestinal (GI) contrast study to exclude intestinal malrotation and basic laboratory screening. An abdominal ultrasound is recommended to exclude renal hydronephrosis in children and biliary disease in adults. Exclusion of metabolic/genetic conditions is warranted in those with specific warning signs, presentation in infants/toddler age, and in those with refractory disease. In the absence of chronic GI symptoms, referral to a GI specialist for upper endoscopy is generally not necessary in children but recommended in adults. A large subset termed migraine-equivalent CVS display strong clinical and genetic features of migraine. A unifying pathophysiologic core concept involves neuronal hyperexcitability and aberrant central modulation of autonomic signals. This is coupled with multiple susceptibility factors including mitochondrial dysfunction/cellular energy deficits, a hyper-responsive hypothalamic-pituitary-adrenal axis and many comorbidities that increase vulnerability to triggering events. CVS episodes are frequently triggered by stressors and intercurrent illnesses. Lifestyle and non-pharmacological interventions thus play a pivotal role in successful management. Pharmacological therapies are categorized into abortive, supportive/rescue, and prophylactic treatments. The majority respond particularly well to migraine-focused treatment strategies.

CONCLUSION

Despite improved characterization and understanding, CVS remains classified as a functional disorder of brain-gut interaction that is often disjointly managed by generalists and subspecialists. Early recognition, evaluation, and management will facilitate care and improve outcomes. Further research into its natural history with common progression to migraine headaches, neuroendocrine mechanisms, and the pathophysiologic relation to migraine diathesis is much needed.

Cyclic Vomiting Syndrome in Children

Cyclic Vomiting Syndrome (CVS) is an underdiagnosed episodic syndrome characterized by frequent hospitalizations, multiple comorbidities, and poor quality of life. It is often misdiagnosed due to the unappreciated pattern of recurrence and lack of confirmatory testing. CVS mainly occurs in pre-school or early school-age, but infants and elderly onset have been also described. The etiopathogenesis is largely unknown, but it is likely to be multifactorial. Recent evidence suggests that aberrant brain-gut pathways, mitochondrial enzymopathies, gastrointestinal motility disorders, calcium channel abnormalities, and hyperactivity of the hypothalamic-pituitary-adrenal axis in response to a triggering environmental stimulus are involved. CVS is characterized by acute, stereotyped and recurrent episodes of intense nausea and incoercible vomiting with predictable periodicity and return to baseline health between episodes. A distinction with other differential diagnoses is a challenge for clinicians. Although extensive and invasive investigations should be avoided, baseline testing toward identifying organic causes is recommended in all children with CVS. The management of CVS requires an individually tailored therapy. Management of acute phase is mainly based on supportive and symptomatic care. Early intervention with abortive agents during the brief prodromal phase can be used to attempt to terminate the attack. During the interictal period, non-pharmacologic measures as lifestyle changes and the use of reassurance and anticipatory guidance seem to be effective as a preventive treatment. The indication for prophylactic pharmacotherapy depends on attack intensity and severity, the impairment of the QoL and if attack treatments are ineffective or cause side effects. When children remain refractory to acute or prophylactic treatment, or the episode differs from previous ones, the clinician should consider the possibility of an underlying disease and further mono- or combination therapy and psychotherapy can be guided by accompanying comorbidities and specific sub-phenotype. This review was developed by a joint task force of the Italian Society of Pediatric Gastroenterology Hepatology and Nutrition (SIGENP) and Italian Society of Pediatric Neurology (SINP) to identify relevant current issues and to propose future research directions on pediatric CVS.

Cannabinoid hyperemesis syndrome: definition, pathophysiology, clinical spectrum, insights into acute and long-term management

Although cannabinoid hyperemesis syndrome (CHS) was first reported more than 15 years ago, it still remains an unfamiliar clinical entity among physicians worldwide. CHS is categorized by Rome IV classification as a functional gastroduodenal disorder. It is characterized by stereotypical episodic vomiting in the setting of chronic, daily cannabis use, with cycles decreasing by the cessation of cannabis. CHS is also associated with abdominal pain reduced by hot baths and showers with comparative well-being between attacks. Thus, its clinical presentation resembles 'classic' cyclic vomiting syndrome, but eliciting a cannabis history is crucial in diagnosing this entity. In acute attacks, parenteral benzodiazepines are very effective. For prevention and long-term management, tricyclic antidepressants such as amitriptyline are the mainstay of therapy requiring doses in the range of 50-200 mg/d to achieve symptom control. In addition, counseling to achieve marijuana cessation, accompanied by antianxiety medications, is necessary for sustaining clinical outcomes. Once the patient is in remission and off marijuana for a period of 6-12 months, then tapering the dose of amitriptyline can be implemented, with the goal of no therapy being achieved in the majority of patients over time. With the legalization of marijuana in many states, CHS will become an increasingly prevalent clinical entity, so educating about CHS is an important goal, particularly for emergency department physicians who generally first encounter these patients.

Postfundoplication retching: Strategies for management

BACKGROUND

Retching is a common symptom in children following antireflux surgery, particularly in those with neurodisability. There is now a strong body of evidence that implicates retching as a major cause of wrap breakdown. Retching is not a symptom of gastroesophageal reflux disease; it is a component of the emetic reflex. In addition to causing wrap breakdown, it is indicative of the presence of nausea. It is a highly aversive experience and warrants treatment in its own right.

METHODS

A framework was constructed for the management of postoperative retching, with strategies targeting different components of the emetic reflex. The impact of differing antireflux procedures upon retching was also considered.

CONCLUSIONS

Once treatable underlying causes have been excluded, the approach includes modifications to feeds and feeding regimens, antiemetics and motility agents. Neuromodulation and other, novel, therapies may prove beneficial in future. Children at risk of postoperative retching may be identified before any antireflux surgery is performed. Fundoplication is inappropriate in these children because it does not treat their symptoms, which are not because of gastroesophageal reflux, and may make them worse. They are also at risk of wrap disruption. Alternative strategies for symptom management should be employed, and fundoplication should be avoided.

LEVEL OF EVIDENCE

II-V.

Pediatric Migraine Phenomena and Variants: Don't Let Them Go Over Your Head

PURPOSE OF REVIEW

Primary care providers, general pediatric neurologists, and other related subspecialty providers require a clear understanding of pediatric migraine with typical aura and its variants.

RECENT FINDINGS

We highlight some of the genetic mutations known to contribute to specific types of migraine with aura, discuss the ophthalmologic phenomena of migraine and call attention to some of the earliest manifestations of migraine in children, many of which have correlates in adulthood. While the majority of headaches in children are migraine with or without aura or tension type, many migraine and aura variants exist. Early and accurate diagnosis of episodic syndromes associated with migraine, as defined by the 2018 ICHD-3 criteria, can help to reduce unnecessary imaging, referrals, cost and anxiety, thereby benefiting patients and their families.

New advances in the treatment of paediatric functional abdominal pain disorders

This Review summarises recent pharmacological and upcoming alternative interventions for children with functional abdominal pain disorders (FAPDs). Pharmacological targets include prokinetics and drugs affecting gastric accommodation to treat postprandial distress and nausea. Similarly, anti-inflammatory agents, junctional protein regulators, analgesics, secretagogues, and serotonin antagonists have a therapeutic role for irritable bowel syndrome. Non-pharmacological treatments include peripheral electrical nerve field stimulation to the external ear, gastric electrical stimulation, dietary interventions such as low fructose and fibre based diets, and nutraceuticals, which include probiotics, prebiotics, and synbiotics. Newer psychological advances such as exposure-based cognitive behavioural therapy, acceptance and commitment therapy, and mindfulness meditation are being investigated for paediatric functional pain. Lastly, alternative therapies such as acupuncture, moxibustion, yoga, and spinal manipulation are also gaining popularity in the treatment of FAPDs.

Perioperative Administration of Emend® (Aprepitant) at a Tertiary Care Children's Hospital: A 12-Month Survey

Introduction

Aprepitant (Emend^®) is a novel antiemetic agent that works through antagonism of neurokinin-1 (NK-1) receptors. To date, there are limited data regarding its use to prevent postoperative nausea and vomiting (PONV) in children. We retrospectively reviewed our initial 12-months experience with aprepitant after it was made available for perioperative use.

Methods

The anesthetic records of patients who received aprepitant were retrospectively reviewed and demographic, surgical, and medication data retrieved.

Results

The study cohort included 31 patients (15 male and 16 female) ranging in age from 4 to 27 years (15.7 ± 7.4 years) and in weight from 14.4 to 175.7 kilograms (59.3 ± 30.2 kgs). Most of the patients (30 of 31) received the capsule form and 1 received the liquid. The average dose of aprepitant administered was 0.9 ± 0.6 mg/kg; however, only one patient received dosing expressed as mg/kg, and the majority received a 40 mg capsule. All of the patients in the cohort had either a previous history of PONV or risk factors for PONV. PONV occurred in the PACU in 1 patient and during the first 24 postoperative hours in 3 additional patients. No adverse effects related to aprepitant use were noted.

Conclusion

Aprepitant was easily added to the preoperative regimen for pediatric patients who may require it. Our approach limited overuse and subsequent cost concerns. Future studies with a comparator group and a greater sample size are needed to demonstrate its efficacy, especially in comparison to time-honored agents such as ondansetron. No adverse effects were noted in our limited study cohort.

Acute Management of Pediatric Cyclic Vomiting Syndrome: A Systematic Review

OBJECTIVES

To synthesize quantitative and qualitative data on pharmacologic interventions of pediatric cyclic vomiting syndrome and their effectiveness in disease management in the acute care setting.

STUDY DESIGN

Using keywords, 799 studies published up from December 1954 to February 2018 were extracted from MEDLINE via Pubmed, Embase via OVID, CINAHL via EBSCO, and Cochrane Controlled Trials Registry. Studies were evaluated for inclusion and exclusion by 2 independent reviewers using predetermined inclusion and exclusion criteria.

RESULTS

The search yielded 84 studies for full review, of which 54 were included in the systematic review. Studies were subsequently separated into 1 group of 6 case series studies containing quantitative data on sumatriptan, ondansetron, phenothiazines, prokinetic agents, carbohydrate, isometheptene, and aprepitant; 1 one group consisting only of qualitative studies containing expert recommendations.

CONCLUSIONS

Ondansetron has the most quantitative and qualitative evidence to support its inclusion in pediatric emergency department protocols as a rescue therapy. Sumatriptan and aprepitant are potential candidates for inclusion as abortive therapies. Qualitative data from retrospective studies and case reports are not applicable to a larger patient population. This report informs a need for controlled, prospective cohort studies and randomized, controlled trials to optimize current management protocols and to develop new medical interventions.

Pediatric and Adolescent Headache

PURPOSE OF REVIEW

This article provides the practicing neurologist with a comprehensive, evidence-based approach to the diagnosis and management of headache in children and adolescents, with a focus on migraine.

RECENT FINDINGS

Four triptans are now labeled by the US Food and Drug Administration (FDA) for acute migraine treatment in adolescents, and rizatriptan is labeled for use in children age 6 and older. For preventive migraine treatment, the Childhood and Adolescent Migraine Prevention trial demonstrated that approximately 60% of children and adolescents with migraine will improve with a three-pronged treatment approach that includes: (1) lifestyle management counseling (on sleep, exercise, hydration, caffeine, and avoidance of meal skipping); (2) optimally dosed acute therapy, specifically nonsteroidal anti-inflammatory drugs and triptans; and (3) a preventive treatment that has some evidence for efficacy. For the remaining 40% of children and adolescents, and for those who would not have qualified for the Childhood and Adolescent Migraine Prevention trial because of having continuous headache or medication-overuse headache, the clinician's judgment remains the best guide to preventive therapy selection.

SUMMARY

Randomized placebo-controlled trials have been conducted to guide first-line acute and preventive migraine treatments in children and adolescents. Future research is needed to guide treatment for those with more refractory migraine, as well as for children and adolescents who have other primary headache disorders.

Emerging Role of Aprepitant in Cannabis Hyperemesis Syndrome

Cannabis hyperemesis syndrome (CHS) is a clinical syndrome associated with prolonged and regular cannabis use. CHS is characterized by recurrent episodes of intractable nausea and vomiting. Given the overlap with other medical conditions and the frequent delay in diagnosis, finding an effective anti-emetic regimen for symptomatic control of CHS can be challenging. We report a case study where aprepitant (Emend) was successfully used as an anti-emetic in the treatment of CHS when all other common anti-emetics failed.

Management of cyclic vomiting syndrome in adults: Evidence review

BACKGROUND

This evidence review was conducted to inform the accompanying clinical practice guideline on the management of cyclic vomiting syndrome (CVS) in adults.

METHODS

We followed the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework and focused on interventions aimed at prophylactic management and abortive treatment of adults with CVS. Specifically, this evidence review addresses the following clinical questions: (a) Should the following pharmacologic agents be used for prophylaxis of CVS: amitriptyline, topiramate, aprepitant, zonisamide/levetiracetam, or mitochondrial supplements? (b) Should the following pharmacologic agents be used for abortive treatment: triptans or aprepitant?

RESULTS

We found very low-quality evidence to support the use of the following agents for prophylactic and abortive treatment of CVS: amitriptyline, topiramate, aprepitant, zonisamide/levetiracetam, and mitochondrial supplements. We have moderate certainty of evidence for the use of triptans as abortive therapy. We found limited evidence to support the use of ondansetron and the treatment of co-morbid conditions and complementary therapies.

CONCLUSIONS

This evidence review helps inform the accompanying guideline for the management of adults with CVS which is aimed at helping clinicians, patients, and policymakers, and should improve patient outcomes.

Cyclic vomiting syndrome: Pathophysiology, comorbidities, and future research directions

Cyclic vomiting syndrome (CVS) is characterized by severe episodic emesis in adults and children. Cannabinoid hyperemesis syndrome is an increasingly recognized CVS-like illness that has been associated with chronic cannabis use. There are significant gaps in our understanding of the pathophysiology, clinical features, comorbidities, and effective management options of CVS. Recommendations for treating CVS are based on limited clinical data, as no placebo-controlled, randomized trials have yet been conducted. Diseases associated with CVS, including migraine, mitochondrial disorders, autonomic dysfunction, and psychiatric comorbidities, provide clues about pathophysiologic mechanisms and suggest potential therapies. We review our current understanding of CVS and propose future research directions with the aim of developing effective therapy. Establishing a multicenter, standardized registry of CVS patients could drive research on multiple fronts including developing CVS-specific outcome measures to broaden our understanding of clinical profiles, to serve as treatment end points in clinical trials, and to provide a platform for patient recruitment for randomized clinical trials. Such a robust database would also facilitate conduct of research that aims to determine the underlying pathophysiological mechanisms and genetic basis for CVS, as well as identifying potential biomarkers for the disorder. Soliciting government and industry support is crucial to establishing the necessary infrastructure and achieving these goals. Patient advocacy groups such as the Cyclic Vomiting Syndrome Association (CVSA), which partner with clinicians and researchers to disseminate new information, to promote ongoing interactions between patients, their families, clinicians, investigators, to support ongoing CVS research and education, must be an integral part of this endeavor.

Guidelines on management of cyclic vomiting syndrome in adults by the American Neurogastroenterology and Motility Society and the Cyclic Vomiting Syndrome Association

The increasing recognition of cyclic vomiting syndrome (CVS) in adults prompted the development of these evidence-based guidelines on the management of CVS in adults, which was sponsored by the American Neurogastroenterology and Motility Society (ANMS) and the Cyclic Vomiting Syndrome Association (CVSA). GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) framework was used and a professional librarian performed the literature search. The expert committee included the President of the CVSA who brought a patient perspective into the deliberations. The committee makes recommendations for the prophylaxis of CVS, treatment of acute attacks, diagnosis, and overall management of CVS. The committee strongly  recommends that adults with moderate-to-severe CVS receive a tricyclic antidepressant (TCA), such as amitriptyline, as a first-line prophylactic medication and receive topiramate or aprepitant as alternate prophylactic medications. Zonisamide or levetiracetam and mitochondrial supplements (Coenzyme Q10, L-carnitine, and riboflavin) are conditionally recommended as alternate prophylactic medications, either alone or concurrently with other prophylactic medications. For acute attacks, the committee conditionally recommends using serotonin antagonists, such as ondansetron, and/or triptans, such as sumatriptan or aprepitant to abort symptoms. Emergency department treatment is best achieved with the use of an individualized treatment protocol and shared with the care team (example provided). The committee recommended screening and treatment for comorbid conditions such as anxiety, depression, migraine headache, autonomic dysfunction, sleep disorders, and substance use with referral to appropriate allied health services as indicated. Techniques like meditation, relaxation, and biofeedback may be offered as complementary therapy to improve overall well-being and patient care outcomes.

Does retching matter? Reviewing the evidence-Physiology and forces

Failure of antireflux surgery is common in children with neurodisability, with a high incidence of persistent or recurrent symptoms, including retching. Anatomical disruption of the wrap is a frequent finding, but what forces underlie this disruption? This article reviews the forces generated during potential wrap-stressing episodes, putting them into the clinical context of wrap failure. Historically, wrap failure has been attributed to pressures arising from a reduction in gastric capacity or compliance, with advocates for an additional, gastric emptying procedure, at the time of fundoplication. However, any postoperative pressure changes are small and insufficient to cause disruption, and evidence of benefit from gastric emptying procedures is lacking. Diaphragmatic stressor events are common in the presence of neurodisability, and there is now increasing recognition of an association between diaphragmatic stressors and wrap breakdown. The analysis in this review demonstrates that the greatest forces on the fundoplication wrap are those associated with retching and vomiting. The direction and magnitude of these forces are sufficient to cause wrap herniation into the thorax, and wrap separation. Clinical series confirm that retching is consistently and strongly associated with wrap breakdown. Retching needs to be addressed if we are to reduce the incidence of wrap failure. Level of Evidence V.

Antiemetic Drug Use in Children: What the Clinician Needs to Know

Vomiting is not only unpleasant for both children and families, but can lead to frequent hospital admission. The persistent vomiting hampers oral intake and increases the risk of dehydration, so the proper use of antiemetic drugs can be useful. The pharmacological treatment of vomiting in children remains a challenge for the pediatrician because several antiemetics are prescribed as "off-label," outside their authorized drug label. Domperidone and ondansetron are the most commonly known antiemetic drugs. A single oral dose of ondansetron has been shown to reduce the risk of recurrent vomiting, the need for intravenous fluids, and hospital admissions in children with acute gastroenteritis. There is enough evidence to support ondansetron administration in children, so the clinical use can be defined as "off-label/on evidence." This review aims to provide an overview of therapeutic use, safety, and main pharmacological properties of antiemetic drugs in children. A comprehensive search of published literature using the PubMed MEDLINE database was carried out to identify all articles published in English from 1998 to February 2018. At present time, the "off-label/on-evidence" use of some antiemetics could improve the success rate of oral rehydration therapy in pediatric emergency settings and to change the management of vomiting with the prevention of the complications.

Episodic syndromes of childhood associated with migraine

PURPOSE OF REVIEW

This review covers recent advances in our understanding of episodic syndromes that may be associated with migraine in children and adolescents, as well as what is known about the treatment of these disorders.

RECENT FINDINGS

The episodic syndromes include benign paroxysmal torticollis, benign paroxysmal vertigo, abdominal migraine, and cyclic vomiting syndrome. Infant colic, or excessive crying in an otherwise healthy and well fed infant, may also fit into this category and is included in the appendix section of the most recent edition of the International Classification of Headache Disorders.

SUMMARY

Episodic syndromes are considered to be early life expressions of migraine in the developing brain. Additional research is needed to determine, which acute and preventive treatments are the most effective in managing these disorders.

Migraine, Cyclic Vomiting Syndrome, and Other Gastrointestinal Disorders

PURPOSE OF REVIEW

Cyclic vomiting syndrome (CVS) is a chronic functional gastrointestinal disorder characterized by episodic nausea and vomiting and is diagnosed using Rome IV criteria. CVS is being recognized more frequently in adults with a prevalence of 2%. It is associated with several functional disorders like autonomic dysfunction, anxiety, and depression, but the strongest association is with migraine. We will elucidate the close relationship between migraine and CVS and briefly discuss its association with other gastrointestinal disorders.

RECENT FINDINGS

We highlight similarities in pathophysiology, clinical presentation, and response to medications between CVS and migraine (tricyclic antidepressants, triptans, antiepileptics). We also discuss novel therapies like CGRP inhibitors which are effective in migraine and have potential for adaptation in patients with CVS. Using migraine as a template should enable investigators to elucidate the mechanisms underlying this disorder, develop novel therapies, and direct future research in CVS.

An overview of the clinical management of cyclic vomiting syndrome in childhood

This narrative review provides an update on cyclic vomiting syndrome pathogenesis, diagnosis and management, based upon studies published after the 2008 North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) official recommendations. The review began with a comprehensive PubMed/Medline search for "cyclic vomiting syndrome", "periodic syndromes" and "pediatrics" from 2000 up to October 2017. Additional papers were identified by reviewing the re-ference lists of retrieved publications. Cyclic vomiting syndrome is a severe, debilitating disorder of the brain-gut axis with unclear pathogenesis, that significantly affects long-term quality of life of affected children and their families. The 2008 NASPGHAN recommendations defined the major clinical, diagnostic and therapeutic peculiarities. Over the last 10 years, advancements in pathogenesis and diagnostic criteria have been made, and new prophylactic and therapeutic strategies have been proposed. These aspects are discussed in this manuscript. For the pediatrician, the major aim is to have early clinical suspicion to avoid diagnostic delay and to start adequate, phase-related, symptom-tailored management.

The Neurokinins: Peptidomimetic Ligand Design and Therapeutic Applications

The neurokinins are indisputably essential neurotransmitters in numerous pathoand physiological events. Being widely distributed in the Central Nervous System (CNS) and peripheral tissues, their discovery rapidly promoted them to drugs targets. As a necessity for molecular tools to understand the biological role of this class, endogenous peptides and their receptors prompted the scientific community to design ligands displaying either agonist and antagonist activity at the three main neurokinin receptors, called NK1, NK2 and NK3. Several strategies were implemented for this purpose. With a preference to small non-peptidic ligands, many research groups invested efforts in synthesizing and evaluating a wide range of scaffolds, but only the NK1 antagonist Aprepitant (EMENDT) and its prodrug Fosaprepitant (IVEMENDT) have been approved by the Food Drug Administration (FDA) for the treatment of Chemotherapy-Induced and Post-Operative Nausea and Vomiting (CINV and PONV, respectively). While non-peptidic drugs showed limitations, especially in side effect control, peptidic and pseudopeptidic compounds progressively regained attention. Various strategies were implemented to modulate affinity, selectivity and activity of the newly designed ligands. Replacement of canonical amino acids, incorporation of conformational constraints, and fusion with non-peptidic moieties gave rise to families of ligands displaying individual or dual NK1, NK2 and NK3 antagonism, that ultimately were combined with non-neurokinin ligands (such as opioids) to target enhanced biological impact.

Cyclic Vomiting Syndrome in Children and Adults: What Is New in 2018?

PURPOSE OF REVIEW

Cyclic vomiting syndrome (CVS) is a disabling functional gastrointestinal disorder characterized by severe vomiting episodes that alternate with symptom-free periods. The purpose of this review is to summarize current knowledge and highlight most recent data on prevalence, diagnosis, management, and impact of CVS in children and adults.

RECENT FINDINGS

Originally thought to be a pediatric disorder, the past decade has witnessed a considerable increase in CVS diagnosed in adults. Despite improved recognition of CVS, without a delineated pathophysiology and specific biomarker, it remains classified as a functional gastrointestinal disorder. Migraines and CVS share a common pathway based on several studies and response to migraine therapy. Recent work has begun to expand the list of comorbidities and identify plausible mechanisms and new therapeutic avenues. This review seeks to highlight best practices and novel therapies for CVS based on expert consensus and review of available literature.

Cyclic vomiting syndrome: diagnostic approach and current management strategies

Cyclic vomiting syndrome (CVS) is a disorder characterized by episodes of nausea and vomiting lasting for 1-5 days followed by asymptomatic periods. The etiology of CVS is unknown, but it shares similar characteristics to migraine headaches. CVS is generally classified as having four phases: prodromal, acute/vomiting/hyperemesis, recovery, and remission/interepisodic. Current management strategies include trigger avoidance, abortive and prophylactic medication therapies, and supportive care. The goal of therapy for the remission phase is prophylaxis of further episodes. Antidepressant, antiepileptic, and antimigraine medications show an overall reduction or remission of CVS symptoms in more than 70% of patients. This article provides a summary of diagnostic strategies and reviews current management strategies for CVS.

Cyclic vomiting syndrome: epidemiology, diagnosis, and treatment

Cyclic-vomiting syndrome (CVS) is a chronic functional gastrointestinal disorder characterized by recurrent episodes of nausea and vomiting. Although once thought to be a pediatric disorder, there has been a considerable increase in recognition of CVS in adults. The exact pathogenesis is unknown and several theories have been proposed. Migraine and CVS share a similar pathophysiology as suggested by several studies. Since there are no specific biomarkers available for this disorder, physicians should rely on Rome criteria for the diagnosis. Due to the lack of randomized control trials, the treatment of CVS is primarily empirical.

Managing cyclic vomiting syndrome in children: beyond the guidelines

Cyclic vomiting syndrome (CVS) in children is characterized by frequent hospitalizations, multiple comorbidities, and poor quality of life. In the absence of robust data, the treatment of CVS remains largely empiric starting with the 2008 NASPGHAN Consensus Statement recommendations of cyproheptadine for children < 5 years of age and amitriptyline for those ≥ 5 years with propranolol serving as the second-line agent. Comprehensive management begins with lifestyle alterations, and extends to medications, supplements, and stress reduction therapies. Standard drug therapy is organized by the four phases of the illness: (1) interictal (preventative medications and mitochondrial supplements), (2) prodromal (abortive agents), (3) vomiting (fluids/energy substrates, antiemetics, analgesics, and sedatives) and (4) recovery (supportive care and nutrition). Because the response to treatment is heterogeneous, clinicians often trial several different preventative strategies including NK1 antagonists, cautious titration of amitriptyline to higher doses, anticonvulsants, Ca²⁺-channel blockers, and other TCA antidepressants. When the child remains refractory to treatment, reconsideration of possible missed diagnoses and further mono- or combination therapy and psychotherapy can be guided by accompanying comorbidities (especially anxiety), specific subphenotype, and when available, genotype. For hospital intervention, IV fluids with 10% dextrose, antiemetics, and analgesics can lessen symptoms while effective sedation in some instances can truncate severe episodes.

CONCLUSION

Although management of CVS remains challenging to the clinician, approaches based upon recent literature and accumulated experience with subgroups of patients has led to improved treatment of the refractory and hospitalized patient. What is Known: • Cyclic vomiting syndrome is a complex disorder that remains challenging to manage. • Previous therapy has been guided by the NASPGHAN Consensus Statement of 2008. What is New: • New prophylactic approaches include NK1 antagonists and higher dosages of amitriptyline. • Strategies based upon comorbidities and subphenotype are helpful in refractory patients.