Risk of abuse of diphenhydramine in children and adolescents with chronic illnesses

Suspected inappropriate use of prescription and non-prescription drugs among requesting customers: A Saudi community pharmacists' perspective

Background

Inappropriate use of medications is a global health concern, and this is attributed to the increased accessibility to prescription and non-prescription (over-the-counter) drugs at community pharmacies. We investigated the inappropriate use of prescription and non-prescription drugs in community pharmacies based on the perspectives of the community pharmacists in Saudi Arabia.

Methods

This was a questionnaire-based, cross-sectional survey which employed convenient sampling (snowball technique) to recruit participants. Being a licensed practicing pharmacist in a retail chain or an independent community pharmacy was the inclusion criteria. Participants were asked to report the drugs they suspected of being inappropriately used along with the frequency, age and gender of the suspected customers. Pharmacists were also asked to mention the action taken to limit inappropriate use at their pharmacy.

Results

A total of 397 community pharmacists completed the questionnaire (86.9 % response rate). 86.4% of the pharmacists suspected some level of abuse or misuse to have occurred. After receiving the questionnaire, the pharmacists reported suspected inappropriate use as encountered during the past three months. Cumulative inappropriate use was reported 1069 times (prescription drugs - 530; non-prescription drugs - 539). The top three inappropriately used prescription-drug categories were gabapentinoids (22.5%), antipsychotics (17.5%) and topical corticosteroids (12.1%). Among non-prescription drugs, cough products (33.2%) ranked first, followed by cold and flu products (29.5%) and first-generation antihistamines (10.8%). The cross tabulations revealed that being in the age range of 26-50 years and being a male was significantly associated (p < 0.001) with abuse/misuse of antipsychotics, antidepressants, gabapentinoids, cough products and first-generation antihistamines. Eye products (Bimatoprost) and skin products abuse/misuse had significant association with female gender (p < 0.001).

Conclusion

The results of our study provide crucial information to the healthcare authorities regarding the medications that can be inappropriately used at the community pharmacies in Saudi Arabia which necessitates implementation of stringent dispensing regulations. Educational programs can be implemented to increase the awareness among public regarding the harmful effects of inappropriate use of drugs.

A different challenge with Benadryl: adolescent diphenhydramine ingestions reported to National Poison Database System, 2007-2020

BACKGROUND

The US Food and Drug Administration released a warning related to potential adverse effects related to intentional misuse or abuse ingestions of diphenhydramine in September 2020. We sought to evaluate adolescent-aged (13-19 y) diphenhydramine ingestions reported to US poison control centers to characterize these exposures, adverse effects, outcomes, and trends in outcomes and reasons for ingestion.

METHODS

The US National Poison Database System was queried for all exposures to diphenhydramine between January 1, 2007 and December 31, 2020.

RESULTS

47,644 ingestions were included for analysis. An increase in the number of ingestions, percentage of cases due to an intentional reason for ingestion and suspected suicide was observed. More serious outcomes, cardiac complications, seizures, and deaths were more common following intentional ingestions and specifically suspected suicide over misuse or abuse.

CONCLUSIONS

Adolescent ingestions of diphenhydramine increased between 2007 and 2020. More serious outcomes, intentional reasons, and suspected suicide also increased over the study interval. Suspected suicide was associated with cardiac complications, seizures, coma, and death at higher rates than misuse or abuse. While misuse and abuse remain a concern, public health interventions focusing on the risk that diphenhydramine pose as an agent of suicide attempt may be of higher impact.

Misuse and dependence of dimenhydrinate: A mixed studies systematic review

BACKGROUND

Dimenhydrinate (DMH) is an antihistamine used to treat nausea and vomiting. Although widely available in pharmacies as an over the counter medication, there have been reports of potential DMH tolerance and dependence and a possible euphoric potential accompanying heavy use (>100 mg/day). Despite the potential for misuse, there is a gap in the literature concerning patterns, characteristics, and potential mechanisms of DMH misuse.

AIMS

This review aimed to synthesize evidence on the pharmacology, clinical effects, and management of DMH misuse and dependence to inform clinical decision making and relevant drug policy.

METHODS

We conducted a systematic review in accordance with the PRISMA guidelines and using Cochrane collaboration methods. We searched seven databases from their inception through July 2019. To be included in the review, studies needed to measure or focus on one or more dimensions of morbidity or mortality related to the misuse of DMH. Quantitative, qualitative and mixed-method studies were included in order to capture the breadth of possible studies. Studies were excluded if they did not fit into the conceptual framework of the study of if they focused primarily on the misuse of other substances. A narrative synthesis of study findings was pursued given the limited capacity for a quantitative meta-analysis.

FINDINGS

We identified 24 studies, which described a range of neuropsychiatric sequelae related to DMH consumption, including seizures, psychosis, depression, intoxication (resembling anticholinergic syndrome) and withdrawal. The sedative and euphoric properties, readily available nature, and low cost of DMH appear to facilitate DMH dependence, which were more commonly reported among individuals who had concurrent psychiatric disorders, displaying symptoms such as low motivation, poor concentration, and delirium. The overall quality of studies identified by this review was low-largely because the majority of studies were case reports or review articles, with few intervention or cohort studies.

CONCLUSIONS

There is some evidence to suggest the existence of DMH-related syndromes involving intoxication, withdrawal, and dependence, more commonly among long-term, heavy DMH consumers. However, higher quality studies are needed to confirm preliminary findings that there may be a biological basis for such syndromes.

Focus on Over-the-Counter Drugs' Misuse: A Systematic Review on Antihistamines, Cough Medicines, and Decongestants

Background: Over the past 20 years or so, the drug misuse scenario has seen the emergence of both prescription-only and over-the-counter (OTC) medications being reported as ingested for recreational purposes. OTC drugs such as antihistamines, cough/cold medications, and decongestants are reportedly the most popular in being diverted and misused. Objective: While the current related knowledge is limited, the aim here was to examine the published clinical data on OTC misuse, focusing on antihistamines (e.g., diphenhydramine, promethazine, chlorpheniramine, and dimenhydrinate), dextromethorphan (DXM)- and codeine-based cough medicines, and the nasal decongestant pseudoephedrine. Methods: A systematic literature review was carried out with the help of Scopus, Web of Science databases, and the related gray literature. For data gathering purposes, both the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) and PROSPERO guidelines were followed (PROSPERO identification code CRD42020209261). Results: After completion of the selection, eligibility, and screening phases, some 92 articles were here taken into consideration; case reports, surveys, and retrospective case series analyses were included. Findings were organized according to the specific OTC recorded. Most articles focused here on DXM (n = 54) and diphenhydramine (n = 12). When specified, dosages, route(s) of administration, toxicity symptoms (including both physical and psychiatric ones), and outcomes were here reported. Conclusion: Results from the systematic review showed that the OTC misusing issues are both widespread worldwide and popular; vulnerable categories include adolescents and young adults, although real prevalence figures remain unknown, due to a lack of appropriate monitoring systems. Considering the potential, and at times serious, adverse effects associated with OTC misusing issues, healthcare professionals should be vigilant, and ad hoc preventative actions should be designed and implemented.

Sleeping without Prescription: Management of Sleep Disorders in Children with Autism with Non-Pharmacological Interventions and Over-the-Counter Treatments

Autism Spectrum Disorders (ASD) are lifelong neurodevelopmental conditions characterized by abnormal social interaction, communication, and behavior. Sleep disturbances represent a common comorbidity in children and adolescents with ASD, with prevalence ranging from 50 to 80%. It has been proved that sleep disruption worsens the symptoms of autism and results in challenging behaviors. Improving sleep should therefore be a primary therapeutic goal. Treatment options range from lifestyle modifications to pharmacological therapy. Several reviews have been written on pharmacological treatments, but very few on the beneficial effects of non-pharmacological interventions, over-the-counter drugs, and nutritional supplements. This study consists of a narrative review of the literature, presenting the available evidence on the following treatments: sleep education, behavioral interventions, complementary and alternative medicine (special mattresses and blankets, massage, aromatherapy, yoga, physical activity), and commonly used over-the-counter medications and supplements (antihistamines, melatonin, tryptophan, carnosine, iron, vitamins, and herbal remedies). For some treatments—such as melatonin and behavioral interventions—effectiveness in ASD is well established in the literature, while other interventions appear of benefit in clinical practice, even if specific studies in children and adolescents with ASD are lacking. Conversely, other treatments only seem to show anecdotal evidence supporting their use.

The Influence of Adding Diphenhydramine Before Initiation of Moderate Sedation with Midazolam and Pethidine for Improving Quality of Colonoscopy

BACKGROUND

Combination of Intravenous benzodiazepines with opiates appears to be essential in order to guarantee high quality of moderate sedation during colonoscopy. Diphenhydramine is recommended for endoscopic procedures in difficult-to-sedate patients However, the studies supporting its use have yielded conflicting results.

OBJECTIVE

To assess the value of adding diphenhydramine hydrochloride before initiation of moderate sedation with midazolam and pethidine for Improving Quality of Sedation during colonoscopy.

METHODS

We conducted a prospective, randomized, double-blind, placebo-controlled study of 150 Patients undergoing diagnostic colonoscopy. Of 150 patients, data were analyzed for 100 patients randomized into two groups: Diphenhydramine group (n = 53) received 50 mg of diphenhydramine intravenously before initiation of moderate sedation with pethidine and midazolam while in placebo group (n = 47) received placebo in addition to pethidine and midazolam. Amount of pethidine and midazolam used and Quality of sedation were assessed.

RESULTS

The mean doses of pethidine was significantly higher in placebo group as compared to diphenhydramine group (69.9 ± 35.4 mg vs 61.2 ± 21.0 mg, p < 0.01) However, no significant difference between the two groups regarding midazolam mean dose (4.9.±2.1 mg vs 4.8 ± 2.0 mg,p = 0.786). More patients in diphenhydramine group were being very satisfied with the procedure as compared to those in placebo group (88.67% vs 59.57%,p < 0.001).Furthermore more endoscopist in diphenhydramine group were being very satisfied with the procedure as compared to those in placebo group (77.35% vs 51.06%,p < 0.001).

CONCLUSIONS

Intravenous diphenhydramine hydrochloride given before initiation of midazolam and pethidine offers a significant Improvement of Quality of moderate Sedation during colonoscopy without increasing the number of sedation related complications.

Practitioner Review: Treatment of chronic insomnia in children and adolescents with neurodevelopmental disabilities

BACKGROUND

Sleep disturbances, in particular insomnia, represent a common problem in children with neurodevelopmental disabilities (NDDs). Currently, there are no approved medications for insomnia in children by the US Food and Drug Administration or European Medicines Agency and therefore they are prescribed off-label. We critically reviewed pediatric literature on drugs as well as nonpharmacological (behavioral) interventions used for sleep disturbances in children with NDDs.

METHODS

PubMed, Ovid (including PsycINFO, Ovid MEDLINE^® , and Embase), and Web of Knowledge databases were searched through February 12, 2017, with no language restrictions. Two authors independently and blindly performed the screening.

RESULTS

Good sleep practices and behavioral interventions, supported by moderate-to-low level evidence, are the first recommended treatments for pediatric insomnia but they are often challenging to implement. Antihistamine agents, such as hydroxyzine or diphenhydramine, are the most widely prescribed sedatives in the pediatric practice but evidence supporting their use is still limited. An increasing body of evidence supports melatonin as the safest choice for children with NDDs. Benzodiazepines are not recommended in children and should only be used for transient insomnia, especially if daytime anxiety is present. Only few studies have been carried out in children's and adolescents' zolpidem, zaleplon, and eszopiclone, with contrasting results. Limited evidence supports the use of alpha-agonists such as clonidine to improve sleep onset latency, especially in attention deficit/hyperactivity disorder subjects. Tricyclic antidepressants, used in adults with insomnia, are not recommended in children because of their safety profile. Trazodone and mirtazapine hold promise but require further studies.

CONCLUSIONS

Here, we provided a tentative guide for the use of drugs for insomnia in children with NDDs. Well-controlled studies employing both objective polysomnography and subjective sleep measures are needed to determine the efficacy, effectiveness, and safety of the currently prescribed pediatric sleep medicines in children with NDDs.

Pediatric Sleep Pharmacology: A Primer

"What will you give my child to help him sleep?" is a common question parents ask and some health care providers abhor hearing. Entire families may suffer when one member does not sleep well. Poor sleep may complicate the management of other comorbid conditions. Health care providers may have received only limited education on sleep disorders and are frequently forced to choose between treatment options that are poorly studied in children. Fortunately, when addressed correctly, many children with chronic sleep disorders may improve their sleep and daytime behavior in a relatively short time. This review provides a framework to help understand the causes of poor sleep in children and the potential pharmacologic options.

Diphenhydramine's role in death investigations: an examination of diphenhydramine prevalence in 2 US geographical areas

PURPOSE

Diphenhydramine (DPH), an over-the-counter first-generation H1 receptor antagonist, is not a common drug of abuse; however, it is encountered in cases of overdose both in the clinical setting and in death investigations. The toxicology laboratories in the Tarrant County Medical Examiner's Office and the District of Columbia Office of The Chief Medical Examiner analyze antemortem and postmortem specimens. Presented are the findings of this evaluation and detailed histories of cases involving DPH.

METHODS

Toxicology reports, autopsy reports, and death investigator narratives were obtained in cases involving DPH at toxic and lethal levels in which this compound was the primary cause or a contributing factor in the death.

RESULTS

Blood concentrations were quantified at a range of 2870 to 21,263 ng/mL. A rare occurrence of DPH abuse via documented intravenous administration leading to death is presented. The cases presented here generally involved much higher concentrations of DPH and an older population than those in previous published data regarding DPH's role in death investigation and abuse.

CONCLUSIONS

As people seek legal alternative drugs to abuse and with the ease of obtaining information via online forums, there is a potential to see an increase in the number of cases involving excessive use of DPH.

Diphenhydramine dependence through deep intramuscular injection resulting in myonecrosis and prolonged QT interval

WHAT IS KNOWN AND OBJECTIVE

Diphenhydramine (DPH) is a first-generation antihistamine, which is useful in treating allergic reaction, and is usually considered innocuous. We describe a retired nurse with history of depression, who began to develop drug-seeking behaviour after her first receiving of an intramuscular (IM) DPH injection due to urticaria.

CASE SUMMARY

The 49-year-old patient had developed IM DPH dependence within 4 months. She needed to receive psychiatric inpatient treatment because of depressive mood, serious myonecrosis over injected sites, and prolongation of QT interval.

WHAT IS NEW AND CONCLUSION

This is the first reported case of DPH dependence through the IM route. Second-generation antihistamines might be better choices for patients with psychiatric illness by reason of their lower effects on central nervous system and lower risk of abuse.

Pediatric sleep pharmacology

This article reviews common sleep disorders in children and pharmacologic options for them. Discussions of pediatric sleep pharmacology typically focus on treatment of insomnia. Although insomnia is a major concern in this population, other conditions of concern in children are presented, such as narcolepsy, parasomnias, restless legs syndrome, and sleep apnea.

Pharmacology of sleep disorders in children and adolescents

There is a high prevalence of sleep disorders in children and an apparent increasing need for pharmacologic management. However, because of the paucity of data available with regards to dosing, efficacy, tolerability, and safety profiles of medications as well as a lack of adequate well-designed clinical trials, medications are currently not approved for the pediatric population by the US Food and Drug Administration. There are no pharmacologic guidelines for the specific sleep disorders or the different pediatric age ranges. Additional research is needed for evidence-based pediatric sleep pharmacotherapy. This article reviews pediatric sleep disorders and the pharmacologic therapeutic options.

Anxiety in medically ill children/adolescents

Anxiety disorders are thought to be one of the most common psychiatric diagnoses in children/adolescents. Chronic medical illness is a significant risk factor for the development of an anxiety disorder, and the prevalence rate of anxiety disorders among youths with chronic medical illnesses is higher compared to their healthy counterparts. Anxiety disorders may develop secondary to predisposing biological mechanisms related to a child's specific medical illness, as a response to being ill or in the hospital, a threatening environment, as a result of other genetic and psychological factors, or as a combination of all these factors. Additionally, exposure to physical pain early in one's life and/or frequent painful medical procedures are correlated with fear and anxiety during subsequent procedures and treatments, and may lead to medical nonadherence and other comorbidities. Anxiety disorders can have serious consequences in children/adolescents with chronic and/or life-limiting medical illnesses. Therefore, proper identification and treatment of anxiety disorders is necessary and may improve not only psychiatric symptoms but also physical symptoms. Behavioral and cognitive methods as well as psychotropic medications are used to treat anxiety disorders in pediatric patients. We will review current treatments for anxiety in children/adolescents with medical illnesses and propose future research directions.

The misuse/abuse of antihistamine antiemetic medication (cyclizine) by cancer patients

Cyclizine is an antihistamine, which is frequently used to manage nausea and vomiting in cancer patients. Antihistamines can be drugs of misuse/abuse, and the article describes four cancer patients who developed such problems after receiving parenteral cyclizine within the inpatient unit of a cancer centre. The article also briefly reviews the literature on the misuse/abuse of cyclizine and other antihistamines.

Cocaine-like neurochemical effects of antihistaminic medications

The pattern of activation of dopamine (DA) neurotransmission in the nucleus accumbens (NAc) of rats produced by H(1) histamine antagonists which have behavioral effects like those of psychostimulant drugs was examined. Diphenhydramine and (+)-chlorpheniramine were compared with triprolidine, a potent and selective H(1) antagonist and (-)-chlorpheniramine which is less active than its enantiomer at H(1) receptors. Affinities of the drugs to DA, serotonin, and norepinephrine transporters at H(1) receptors and potencies for DA uptake inhibition in striatal synaptosomes were determined to assess mechanisms by which the compounds increased DA levels. Intravenous diphenhydramine (1.0-3.0 mg/kg) (+)- and (-)-chlorpheniramine (1.0-5.6 mg/kg) but not triprolidine (1.0-3.0 mg/kg) elicited a cocaine-like pattern of stimulation of DA transmission with larger effects in the NAc shell than core. The absence of stereospecific effects with chlorpheniramine enantiomers along with the lack of an effect with triprolidine suggest that the effects on DA transmission were not related to H(1) receptor antagonism. Although in vivo potencies were not directly related to DA transporter affinities, it is hypothesized that actions at that site modulated by other actions, possibly those at the serotonin transporter, are primarily responsible for the neurochemical actions of the drugs on DA neurotransmission and might underlie the occasional misuse of these medications.

Pediatric sleep pharmacology

This article reviews the most common pharmacologic options in the treatment of sleep disorders in children. Despite the high prevalence of sleep disorders in children, there is a paucity of education and information available on the pharmacologic management of sleep disorders in children. The principles of sleep physiology and pathophysiology that help provide more rational pharmacologic management are discussed. Medications are typically not Food and Drug Administration (FDA) approved for the pediatric age range or for the specific sleep disorder. Medications have a role for insomnia, narcolepsy, parasomnias, and sleep-related movement disorders. The available choices of hypnotics are reviewed. Medications to increase alertness of narcoleptics and decrease cataplexy are discussed. The use of dopaminergic agents for Restless Legs Syndrome is reviewed. The potential use of medication in sleep apnea is also reviewed. Pharmacologic guidelines need to be developed specifically for sleep disorders in children. Ideally, these guidelines should be FDA approved for the specific sleep disorder and for the pediatric age range. The development of easy to swallow, chewable or liquid forms of these medications are needed. Training programs should play the lead role in enhancing pediatricians' knowledge of the pharmacologic treatment of sleep disorders in children.

Pediatric sleep pharmacology: you want to give my kid sleeping pills?

There is a need for greater information about the pharmacologic management of sleep disorders in children. Pharmacologic guidelines must be developed specifically for sleep disorders in children. Ideally, these guidelines should be approved by the Food and Drug Administration for a specific sleep disorder or for the pediatric age range. This approval prevents physicians from being forced to prescribe medications as an "off label" indication. Development of easy-to-swallow, chewable, or liquid forms of these medications would be well received by parents everywhere. When these are not available, instructions for compounding these medications into a suspension by pharmacists are needed. Integration of behavioral and pharmacologic treatments may yield better patient outcomes. This approach requires pediatricians to have a comprehensive understanding of clinical sleep disorders in children. Training programs should play the lead role in enhancing pediatricians' knowledge of the pharmacologic treatment of sleep disorders in children.

Adverse effects of sedatives in children

The application of sedation/analgesia in paediatric patients is rapidly expanding as less invasive, non-operative techniques of diagnosis and treatment are applied to the paediatric population. Medical providers who are asked to provide sedation may include radiologists, paediatricians, nurses and emergency physicians, as well as anaesthesiologists and intensive care physicians. At the same time, the range of drugs used in these settings has expanded considerably. As there is no single drug fulfilling the criteria for the ideal sedative (rapid-onset, rapid recovery, no adverse effects, immobility appropriate to procedure being performed), multiple drugs may be used in combination. It is imperative that practitioners using drugs for sedation/analgesia in children be aware of the adverse effect profile(s) of these drugs, both individually and in combination. The purpose of this review is to describe the adverse effects of sedative and reversal agents currently used in paediatric sedation/analgesia.

Mental status changes in children with systemic cancer

Mental status changes are second only to headaches as a cause of neurologic consultation in children with systemic cancer, but the literature on these patients is sparse. This study consisted of a review of the consultations because of changes in mental status in patients with pediatric cancer, with analysis of clinical presentation, etiology, underlying cancer, and neuroradiologic findings. Hematologic cancers were the underlying disorder in slightly more than one half of the patients. The majority of children suffered from iatrogenically induced encephalopathy, predominantly opioid-related. Several drugs were associated with depressed sensorium, but a pure metabolic deficit was rare. One third of the patients had multiple causative factors. Neuroimaging studies were particularly helpful in children with unexplained somnolence but were less useful if the patient had hallucinations. The absence of localizing signs in children with unexplained somnolence or stupor did not exclude the presence of structural disease. Altered mental status is frequently observed in children being actively treated for systemic cancer. The majority of children suffer from iatrogenically induced encephalopathy, predominantly opioid-related. The presence of hallucinations favors a toxic-metabolic dysfunction, especially if associated with myoclonus. Under those circumstances a neuroimaging study is usually unrewarding. If the main complaint is unexplained somnolence without hallucinations or delusions, the performance of a brain imaging study is mandatory, even in the absence of localizing signs.