Acute treatment of migraine with dihydroergotamine nasal spray. Dihydroergotamine Working Group

Dihydroergotamine mesylate nasal spray: an acute treatment option for migraine in adults

INTRODUCTION

Although the landscape of migraine symptomatic treatment has been enriched by novel effective drugs, it is mandatory to critically reappraise older molecules to ascertain whether they could still represent reliable alternatives in specific endophenotypes of patients or migraine attacks. Among these, dihydroergotamine (DHE) nasal spray has been shown to be effective and is characterized by greater tolerability and manageability than the parenteral DHE formulation.

AREAS COVERED

In this narrative review, the authors describe the pharmacodynamic and pharmacokinetic properties of DHE nasal spray and explore the results of the trials which explored its efficacy, safety and tolerability as migraine symptomatic treatment. They also discuss the limitations of the classically used device and the attempts that several companies are carrying out to generate devices warranting a more reproducible drug absorption.

EXPERT OPINION

DHE nasal spray could be considered as rescue treatment in patients who have failed other symptomatic therapeutic strategies. Nevertheless, in the perspective of tailored therapy, the intranasal route of administration and the consequent rapid onset of action may represent benefits putatively making DHE a treatment of choice for challenging migraine attacks such as those with nocturnal onset or quickly reaching the climax of both headache and neurovegetative associated symptoms.

Efficacy and safety of intranasal agents for the acute treatment of migraine: a systematic review and network meta-analysis

BACKGROUND

Intranasal agents may be ideal for the treatment of migraine patients. Many new acute intranasal-specific therapies have been developed, but few of them have been directly compared. The aim of this network meta-analysis (NMA) was to compare the efficacy and safety of various intranasal agents for the treatment of acute migraine in adult patients.

METHODS

The Cochrane Register of Controlled Trials, Embase, and PubMed were searched from inception to 15 August 2023. Randomized controlled trials (RCTs) using intranasal agents (no restrictions on dose, formulation, dosing regimen or timing of the first dose) to treat adult patients with acute migraine were included. The primary efficacy endpoint was pain freedom at 2 h, and the primary safety endpoint was adverse events (AEs). The analysis process followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Nineteen studies (21 RCTs, 9738 participants) were included. Compared to the placebo, 5 mg of zolmitriptan using a conventional liquid nasal spray device was the most effective for pain freedom at 2 h [odds ratio (OR): 4.67, 95% confidence interval (CI): 3.43 to 6.43] and 24 h (OR: 5.49, 95% CI: 3.58 to 8.42) among all the interventions. Butorphanol nasal spray 1 mg was the most effective (OR: 8.62, 95% CI: 1.11 to 66.92) for pain freedom at 1 h, but with low-quality evidence. DFN-02 presented the highest freedom from nausea (OR: 4.95, 95% CI: 1.29 to 19.01) and phonophobia (OR: 5.36, 95% CI: 1.67 to 17.22) at 2 h, albeit with lower odds of achieving complete pain freedom. ROX-828 showed the highest improvement in freedom from photophobia at 2 h (OR: 4.03, 95% CI: 1.66 to 9.81). Dihydroergotamine nasal spray was significantly associated with the highest risk of AEs (OR: 9.65, 95% CI: 4.39 to 21.22) and was not recommended for routine use. Zavegepant nasal spray demonstrated the lowest risk of AEs (OR: 2.04, 95% CI: 1.37 to 3.03). The results of sensitivity analyses for the primary endpoints (pain freedom at 2 h and AEs) were generally consistent with those of the base case model.

CONCLUSIONS

Compared with other new intranasal-specific therapies in treating migraine attacks, zolmitriptan nasal spray 5 mg was the most effective agent for pain freedom at 2 h. Zavegepant nasal spray 10 mg had the fewest adverse side effects.

Sodium Valproate Versus Dopamine Antagonists for Acute Migraine in the Emergency Department: A Systematic Review

BACKGROUND

Migraine is a common primary headache disorder diagnosed in the emergency department (ED). This systematic review sought to compare the efficacy of sodium valproate (SV) to dopamine antagonists (DA) in relieving pain due to acute migraine.

METHODS

Two research librarians helped create a search strategy including Embase, Ovid Medline, and the Cochrane Database of Clinical Trials from inception to June 1, 2020, updated May 19, 2021. Two investigators identified randomized control trials (RCTs) including adult patients with acute migraine presenting to the ED or acute clinical setting comparing SV to a DA with the aim of relieving pain. Primary outcome was headache relief at 1 hour from treatment. Secondary outcomes included pain relief at 24 hours, relief of associated symptoms (e.g. nausea, photo-/phonophobia, etc.), and need for rescue analgesia. Meta-analysis was performed and presented as odds ratios.

RESULTS

Four RCTs with 470 patients were identified from an initial pool of 454 titles. Two studies compared SV to a DA alone and two compared SV to a DA plus one other agent (sumatriptan or dihydroergotamine). Three studies were included for meta-analysis. Pain relief had a pooled odds ratio of 1.14 at 1 hour and 0.42 at 24 hours. Three articles reporting the need for rescue analgesia had pooled odds ratio of 2.76.

CONCLUSIONS

Sodium valproate is not more effective than DA at reducing migraine headache pain at 1 hour and less effective at 24 hours. Dopamine antagonists should be used over SV for the management of patients with acute migraine.

Acute Treatments for Episodic Migraine in Adults: A Systematic Review and Meta-analysis

IMPORTANCE

Migraine is common and can be associated with significant morbidity, and several treatment options exist for acute therapy.

OBJECTIVE

To evaluate the benefits and harms associated with acute treatments for episodic migraine in adults.

DATA SOURCES

Multiple databases from database inception to February 24, 2021.

STUDY SELECTION

Randomized clinical trials and systematic reviews that assessed effectiveness or harms of acute therapy for migraine attacks.

DATA EXTRACTION AND SYNTHESIS

Independent reviewers selected studies and extracted data. Meta-analysis was performed with the DerSimonian-Laird random-effects model with Hartung-Knapp-Sidik-Jonkman variance correction or by using a fixed-effect model based on the Mantel-Haenszel method if the number of studies was small.

MAIN OUTCOMES AND MEASURES

The main outcomes included pain freedom, pain relief, sustained pain freedom, sustained pain relief, and adverse events. The strength of evidence (SOE) was graded with the Agency for Healthcare Research and Quality Methods Guide for Effectiveness and Comparative Effectiveness Reviews.

FINDINGS

Evidence on triptans and nonsteroidal anti-inflammatory drugs was summarized from 15 systematic reviews. For other interventions, 115 randomized clinical trials with 28 803 patients were included. Compared with placebo, triptans and nonsteroidal anti-inflammatory drugs used individually were significantly associated with reduced pain at 2 hours and 1 day (moderate to high SOE) and increased risk of mild and transient adverse events. Compared with placebo, calcitonin gene-related peptide receptor antagonists (low to high SOE), lasmiditan (5-HT1F receptor agonist; high SOE), dihydroergotamine (moderate to high SOE), ergotamine plus caffeine (moderate SOE), acetaminophen (moderate SOE), antiemetics (low SOE), butorphanol (low SOE), and tramadol in combination with acetaminophen (low SOE) were significantly associated with pain reduction and increase in mild adverse events. The findings for opioids were based on low or insufficient SOE. Several nonpharmacologic treatments were significantly associated with improved pain, including remote electrical neuromodulation (moderate SOE), transcranial magnetic stimulation (low SOE), external trigeminal nerve stimulation (low SOE), and noninvasive vagus nerve stimulation (moderate SOE). No significant difference in adverse events was found between nonpharmacologic treatments and sham.

CONCLUSIONS AND RELEVANCE

There are several acute treatments for migraine, with varying strength of supporting evidence. Use of triptans, nonsteroidal anti-inflammatory drugs, acetaminophen, dihydroergotamine, calcitonin gene-related peptide antagonists, lasmiditan, and some nonpharmacologic treatments was associated with improved pain and function. The evidence for many other interventions, including opioids, was limited.

Nasal Delivery of Acute Medications for Migraine: The Upper Versus Lower Nasal Space

The acute treatment of migraine requires effective drugs that are well tolerated and provide rapid and consistent pain relief. Oral tablets are the most commonly used acute treatment for migraine; however, their effectiveness is limited by the rate of gastrointestinal (GI) tract absorption and first-pass hepatic metabolism, and they may not be ideal for patients experiencing GI motility issues. Nasal delivery is an attractive alternative route as it may circumvent GI tract absorption, avoid first-pass metabolism in the liver, and potentially reduce the frequency of GI adverse events. The large surface area and high vascularity within the nose may permit rapid absorption of therapeutics into the systemic circulation, allowing for rapid onset of action. However, the site of drug deposition (upper versus lower nasal cavity) may influence drug pharmacokinetics. Most approved nasal migraine therapies target the lower nasal space where the epithelium is less permeable, and they may be quickly cleared away due to increased ciliary function or dripping from the nose or swallowing, resulting in variable absorption and limited bioavailability. Together with its abundant vascularization, relative mucosal thickness stability, and low clearance rates, the upper nasal space harnesses the benefits of nasal delivery to potentially maximize drug efficacy.

Individual differences of maladaptive brain changes in migraine and their relationship with differential effectiveness of treatments

Migraine is a difficult disorder to identify with regard to its pathophysiological mechanisms, and its treatment has been primarily difficult owing to interindividual differences. Substantial rates of nonresponsiveness to medications are common, making migraine treatment complicated. In this review, we systematically analyzed recent studies concerning neuroimaging findings regarding the neurophysiology of migraine. We linked the current imaging research with anecdotal evidence from interindividual factors such as duration and pain intensity of migraine, age, gender, hormonal interplay, and genetics. These factors suggested the use of nonpharmacological therapies such as transcranial magnetic stimulation, transcranial direct current stimulation, and placebo therapy for the treatment of migraine. Finally, we discussed how interindividual differences are related to such nondrug treatments.

A Phase 1, Randomized, Open-Label, Safety, Tolerability, and Comparative Bioavailability Study of Intranasal Dihydroergotamine Powder (STS101), Intramuscular Dihydroergotamine Mesylate, and Intranasal DHE Mesylate Spray in Healthy Adult Subjects

Objective

To investigate and compare the safety and the pharmacokinetics of dihydroergotamine (DHE) after administration of intranasal DHE powder (STS101), intranasal DHE spray (Migranal^®), and intramuscular (IM) DHE injection in healthy subjects.

Methods

This was a 2‐part, active‐controlled, 3‐period crossover study over 3 weeks, separated by 1‐week washout periods. In part 1, 3 ascending dosage strengths of STS101 (1.3, 2.6, and 5.2 mg) were administered to 15 healthy subjects with no history of migraine. In part 2, 27 healthy subjects were administered 1 dose each of STS101 5.2 mg, Migranal DHE Mesylate Liquid Nasal Spray 2.0 mg, and IM DHE Mesylate 1.0 mg in a randomized order. Liquid chromatography, tandem mass spectrometry was used to determine plasma levels of DHE and its major metabolite, 8′OH‐DHE. Pharmacokinetic parameters (C_max, T_max, AUC_0‐2 h, AUC_0‐48 h, AUC_0‐inf, and t_1/2) for DHE and metabolite were calculated. Geometric means and 90% confidence intervals of log‐transformed data were calculated and the ratio of means compared. Safety was evaluated by monitoring adverse events, vital signs, electrocardiograms, subjective and objective assessments of nasal signs and symptoms, and changes in laboratory parameters. The study is registered as NCT03874832.

Results

Forty‐three subjects were enrolled and received study medication. Forty completed all study activities, 14 in part 1 and 26 in part 2. In part 1, DHE plasma levels showed a dose‐dependent increase, with STS101 5.2 mg reaching a mean C_max of 1870 pg/mL with a T_max of 23 minutes. In part 2, STS101 5.2 mg showed rapid absorption, achieving mean DHE plasma concentrations of 1230 and 1850 pg/mL at 10 and 15 minutes after administration, respectively. In comparison to Migranal, STS101 5.2 mg showed approximately 2‐fold higher C_max (2175 vs 961 pg/mL), AUC_0‐2 h (2979 vs 1316 h × pg/mL), and AUC_0‐inf (12,030 vs 6498 h × pg/mL), respectively. The mean AUC_0‐inf of STS101 5.2 mg was comparable to IM DHE (12,030 vs 13,650 h × pg/mL). STS101 5.2 mg showed substantially lower variability compared to Migranal for C_max (41% vs 76%), AUC_0‐2 h (39% vs 75%), and AUC_0‐inf (39% vs 55%). The incidence of treatment emergent AEs (TEAEs), all mild and transient, reported in parts 1 and 2 combined was 9/15 (60%), 5/15 (33%), and 16/41 (39%) of the subjects after 1.3, 2.6, and 5.2 mg STS101, respectively, and 4/26 (15%) and 5/27 (19%) of the subjects after IM DHE and Migranal, respectively.

Conclusion

STS101 showed rapid absorption, achieving effective DHE plasma concentrations within 10 minutes. It achieved substantially higher C_max, AUC_0‐2 h and AUC_0‐inf, compared to Migranal suggesting potentially better efficacy than Migranal. Its variability was better than Migranal, thus offering improved consistency of response. AUC_0‐inf was comparable to IM DHE, suggesting prolonged action and low recurrence. Additionally, the C_max was sufficiently low to avoid any significant nausea reported with IV DHE. Thus, STS101 is an easy to administer, non‐injected, acute treatment for migraine, with a favorable tolerability profile and is expected to provide rapid and consistent freedom from pain and associated migraine symptoms without recurrence.

Dihydroergotamine (DHE) - Then and Now: A Narrative Review

OBJECTIVE

To provide a narrative review of clinical development programs for non-oral, non-injectable formulations of dihydroergotamine (DHE) for the treatment of migraine.

BACKGROUND

Dihydroergotamine was one of the first "synthetic drugs" developed in the 20th century for treating migraine. It is effective and recommended for acute migraine treatment. Since oral DHE is extensively metabolized, it must be given by a non-oral route. Intravenous DHE requires healthcare personnel to administer, subcutaneous/intramuscular injection is challenging to self-administer, and the approved nasal spray formulation exhibits low bioavailability and high variability that limits its efficacy. Currently there are several attempts underway to develop non-oral, non-injected formulations of DHE.

METHOD

A systematic search of MEDLINE/PubMed and ClinicalTrials.gov databases, then narrative review of identified reports, focusing on those published in the last 10 years.

RESULTS

Of 1881 references to DHE from a MEDLINE/PubMed search, 164 were from the last 10 years and were the focus of this review. Further cross reference was made to ClinicalTrials.gov for 19 clinical studies, of which some results have not yet been published, or are studies that are currently underway. Three nasal DHE products are in clinical development, reawakening interest in this route of delivery for migraine. Other routes of DHE administration have been, or are being, explored.

CONCLUSION

There is renewed appreciation for DHE and the need for non-oral, non-injected delivery is now being addressed.

Is the Generally Held View That Intravenous Dihydroergotamine Is Effective in Migraine Based on Wrong "General Consensus" of One Trial? A Critical Review of the Trial and Subsequent Quotations

BACKGROUND

The claim that parenteral dihydroergotamine (DHE) is effective in migraine is based on one randomized, placebo-controlled, crossover trial from 1986. The aim of this review was to critically evaluate the original article. It was also found to be of interest to review quotes concerning the results in the more than 100 articles subsequently referring to the article.

METHODS

The correctness of the stated effect of intravenous DHE in the randomized clinical trial (RCT) was first critically evaluated. Then, Google Scholar was searched for references to the article and these references were classified as to whether they judged the reported RCT as positive or negative.

RESULTS

The design of the RCT, with a crossover within one migraine attack, only allows evaluation of the results for the first period and the effect of DHE and placebo were quite comparable. About 151 references were found for the article in Google scholar. Among the 95 articles with a judgment on the efficacy of intravenous DHE in the RCT, 90 stated that DHE was effective or likely effective whereas only 5 articles stated that DHE was ineffective.

CONCLUSIONS

Despite a "negative" RCT, authors of subsequent articles on the efficacy of parenteral DHE overwhelmingly reported this RCT as "positive." This is probably due to the fact that the authors concluded in the abstract that DHE is effective, and to a kind of "wrong general consensus."

Dihydroergotamine Tartrate Induces Lung Cancer Cell Death through Apoptosis and Mitophagy

BACKGROUND

Mitochondria have emerged as a major target for anticancer therapy because of their critical role in cancer cell survival. Our preliminary works have suggested that dihydroergotamine tartrate (DHE), an antimigraine agent, may have effects on mitochondria.

METHODS

We examined the effect of DHE on the survival of several lung cancer cells and confirmed that DHE suppressed diverse lung cancer cell growth effectively. To confirm whether such effects of DHE would be associated with mitochondria, A549 cells were employed for the evaluation of several important parameters, such as membrane potential, reactive oxygen species (ROS) generation, apoptosis, ATP production and autophagy.

RESULTS

DHE decreased membrane permeability, increased ROS generation as well as apoptosis, and disturbed ATP production. Eventually, mitophagy was activated for damaged mitochondria.

CONCLUSION

Taken together, our findings demonstrate that DHE induces lung cancer cell death by the induction of apoptosis and mitophagy, thus suggesting that DHE can be developed as an anti-lung cancer therapeutic agent.

Treatment of headache following triptan failure after successful triptan therapy

OPINION STATEMENT

Triptans should remain the first choice in migraine abortive treatment. They are not always effective or adequate for specific patients. Before declaring a triptan in appropriate for a given patient, the provider ought to be analytical about the rationale and especially the use of objective efficacy outcome measures and ensure that treatment is prescribed and used appropriately. Other ergot derivatives, especially dihydroergotamine, may on one hand share common contraindications of triptans but on the other hand can be quite effective where triptans failed. Non-steroids are simple, readily available, and overall safe, and evidence for their efficacy in migraine is plentiful. Opioid analgesics are blatantly overprescribed especially in non-complicated migraine patients. These should be used with great care and restraint and closely monitored. Frequent opioid usage often leads to tolerance, dependence, and medication overuse headache. Neurostimulation is gaining momentum in the armamentarium of migraine management but at the present time remains primarily focused on prophylaxis, yet abortive use is expected to grow.

Acute Migraine Treatment in Adults

There are many options for acute migraine attack treatment, but none is ideal for all patients. This study aims to review current medical office-based acute migraine therapy in adults and provides readers with an organized approach to this important facet of migraine treatment. A general literature review includes a review of several recent published guidelines. Acetaminophen, 4 nonsteroidal anti-inflammatory drugs (NSAIDs) (ibuprofen, acetylsalicylic acid [ASA], naproxen sodium, and diclofenac potassium), and 7 triptans (almotriptan, eletriptan, frovatriptan, naratriptan, rizatriptan, sumatriptan, and zolmitriptan) have good evidence for efficacy and form the core of acute migraine treatment. NSAID-triptan combinations, dihydroergotamine, non-opioid combination analgesics (acetaminophen, ASA, and caffeine), and several anti-emetics (metoclopramide, domperidone, and prochlorperazine) are additional evidence-based options. Opioid containing combination analgesics may be helpful in specific patients, but should not be used routinely. Clinical features to be considered when choosing an acute migraine medication include usual headache intensity, usual rapidity of pain intensity increase, nausea, vomiting, degree of disability, patient response to previously used medications, history of headache recurrence with previous attacks, and the presence of contraindications to specific acute medications. Available acute medications can be organized into 4 treatment strategies, including a strategy for attacks of mild to moderate severity (strategy one: acetaminophen and/or NSAIDs), a triptan strategy for patients with severe attacks and for attacks not responding to strategy one, a refractory attack strategy, and a strategy for patients with contraindications to vasoconstricting drugs. Acute treatment of migraine attacks during pregnancy, lactation, and for patients with chronic migraine is also discussed. In chronic migraine, it is particularly important that medication overuse is eliminated or avoided. Migraine treatment is complex, and treatment must be individualized and tailored to the patient's clinical features. Clinicians should make full use of available medications and formulations in an organized approach.

Dihydroergotamine: a review of formulation approaches for the acute treatment of migraine

Dihydroergotamine (DHE) was first used to treat migraine in 1945 and is currently included among migraine-specific treatments for moderate-severe migraine. DHE may be administered through several routes of delivery, with efficacy and tolerability varying among formulations. We review DHE formulation approaches for the acute treatment of migraine, reviewing pharmacokinetics/dynamics and comparing clinical response among various formulations. Pharmacokinetic properties vary among DHE formulations, with peak concentration occurring in 6 min with intravenous, 34 min with intramuscular, 56 min with intranasal, 12 min with oral inhalation and 75 min with oral administration. DHE is a potent agonist at serotonin 5-HT1B and 5-HT1D receptors. Adverse effects due to binding to select adrenergic and dopaminergic receptors are significantly less with orally inhaled than intravenous DHE when comparing therapeutically effective doses. Among parenteral formulations (including subcutaneous, intramuscular, intravenous and nasal spray), efficacy is superior with injectable dosing. Nasal spray DHE is generally more effective than placebo, but less effective than sumatriptan. Orally inhaled DHE is likewise more effective than placebo, but there are no head-to-head comparisons with triptans available for review. Adverse effects, particularly nausea, may limit use of parenteral DHE. Nausea is generally less frequent with non-injectable dosing.

Relatively slow and long-lasting antimigraine effect of dihydroergotamine is most likely due to basic pharmacological attributes of the drug: A review

Introduction

If a drug has a slow dissociation from the receptor this can result in a long duration of effect and a slow effect. The long duration of the antimigraine effect of dihydroergotamine (DHE) has been reported previously whereas a possible slow onset of DHE’s antimigraine effect, which is the subject of this review, has only rarely been mentioned.

Methods

Eight randomised, controlled trials (RCT) with DHE for acute treatment with migraine were selected from the literature. The speed of the effect of DHE in migraine was evaluated by plotting the effect up to four hours against time.

Findings

Subcutaneous DHE 1 mg was inferior to subcutaneous sumatriptan 6 mg for headache relief for the first two hours but equally effective after three hours. After intranasal DHE 2 mg the mean therapeutic gain increased slowly up to four hours. For orally inhaled DHE 0.5 mg there was a considerable time lag between therapeutic gain (maximum after two hours) and plasma concentrations of DHE (Tmax = 12 min).

Conclusion

DHE has a slow dissociation from the receptor; and this basic attribute of the drug is the most likely cause of the general relatively slow anti-migraine effect of DHE.

Where is dihydroergotamine mesylate in the changing landscape of migraine therapy?

IMPORTANCE OF THE FIELD

Migraine affects approximately 18% of women and 6% of men, and has an immense impact on quality of life and productivity. Advancement in therapeutic options has been slow. For many patients with difficult-to-treat migraine, the appropriate use of dihydroergotamine mesylate (DHE) can result in treatment success and unprecedented patient satisfaction.

AREAS COVERED IN THIS REVIEW

Migraine treatment guidelines regarding the role of DHE are highlighted. An overview of the market for antimigraine drugs is provided in the context of DHE, since its introduction in 1943, and the novel agents that are likely to be available in the near future. An extensive literature search was undertaken using Medline and the Cochrane Systematic Review and Clinical Trial databases.

WHAT THE READER WILL GAIN

An understanding of which migraine patients are likely to benefit maximally from treatment with DHE in its various forms.

TAKE HOME MESSAGE

In the most difficult patient groups - including those with status migrainosus, migraine recurrence, medication-overuse headache, and chronic daily headache - DHE has therapeutic efficacy superior to other agents. The side-effect profile of DHE is more benign than is often perceived and should not be a deterrent for use in well-chosen cases.

Migraine, allodynia, and implications for treatment

Allodynia--perception of pain from non-noxious stimuli--is a common clinical feature in various pain syndromes. The significance for migraine has increasingly been recognized and the pathophysiology has been investigated in detail. Allodynia is a marker for sensitization of central trigeminal neurons. Intensity and persistence of allodynic symptoms are a function of duration of migraine attacks, frequency of attacks, and migraine history. It has been hypothesized that treatment success with triptans may be severely impaired in the presence of allodynia. However, randomized controlled trials did not confirm that. Treatment with cyclooxygenase inhibitors and dihydroergotamine does not seem to be limited by allodynia; these medications may be able to reverse allodynia. Data on the new class of calcitonin-gene related-peptide antagonists are not yet available. Additional and more refined randomized controlled trials, focusing on methodological issues pertaining to the determination of allodynia, are warranted to resolve the true relationship between allodynia and treatment response. Regardless--based on available randomized controlled trials--the recommendation prevails to initiate abortive treatment as soon as possible after attack onset when pain is still mild.

DHE in the pharmacotherapy of migraine: potential for a larger role

Despite a large array of currently marketed, frequently effective drugs for the acute treatment of migraine headache, comprising various classes and formulations, predictably reliable treatment for most headache types is often lacking. Dihydroergotamine mesylate (DHE) is a comparatively safe and effective therapy for migraine headache that could potentially be used for a broader range of headache types than occurs at present. The features of DHE supporting this assertion include (1) effectiveness in terminating severe, long-lasting headaches, (2) rapid onset of action, (3) very low rates of headache recurrence, (4) minimal risk of medication-overuse headache, and (5) in the nasal spray formulation, suitability for outpatients (especially patients who are very nauseated or vomiting, potentially obviating the need for an office or hospital visit for acute care). Conditions or circumstances for which there are data supporting the expanded use of DHE include menstrual migraine, migraine with central sensitization and cutaneous allodynia, medication-overuse headache, migraine recurrence, and status migrainosus. The introduction of the intranasal formulation of DHE provides both pharmacologic and patient-convenience advantages for use in migraine therapy. This article reviews the rationale for the use of DHE in these common, often difficult-to-treat migraine forms.

Pharmacology of dihydroergotamine and evidence for efficacy and safety in migraine

Dihydroergotamine mesylate (DHE), an ergot alkaloid, has been extensively utilized and studied in the treatment of episodic and chronic migraine. This article reviews the pharmacokinetics, pharmacodynamics, and clinical efficacy and safety of DHE, particularly in comparison to ergotamine tartrate (ET), a similar ergot alkaloid with a long history of use in the treatment of migraine. Structural differences between these 2 compounds account for clinically important distinctions in their pharmacokinetic, pharmacodynamic, and adverse event profiles. DHE is a significantly less potent arterioconstrictor than is ET, which makes it a potentially much safer drug. In addition, DHE is associated with a markedly lower incidence of medication-withdrawal headache, nausea, and vomiting than is ET. The safety and efficacy data presented here are derived from clinical trials and case series involving DHE administered by intravenous infusion, intramuscular or subcutaneous injection, or intranasal spray.

Nasal delivery of antimigraine drugs: clinical rationale and evidence base

The intranasal route of administration for antimigraine drugs offers many theoretical and practical advantages. A drug that is administered intranasally is absorbed by the highly vascular mucous membranes of the nose, which allows for rapid delivery of un-metabolized drug to the central nervous system. The onset of action is thus considerably earlier than with oral administration requiring gastrointestinal absorption. The intranasal route also provides several practical advantages, such as greater acceptability to patients because of the noninvasive mode of delivery, the ability to take medication when severe nausea or vomiting is present, and a better adverse event profile. Three antimigraine drugs are available in intranasal formulation: dihydroergotamine, sumatriptan, and zolmitriptan. This article reviews the pharmacology, efficacy, safety, and tolerability of these agents. All are well tolerated by patients and have demonstrated efficacy in the treatment of migraine headache. Each of these drugs has a unique pharmacokinetic and pharmacodynamic profile, which may support a clinical preference for one intranasal agent over another in treating patients with specific headache features.

A Practical Approach to Headache Treatment

The World Health Organization cites migraine headache as one of the 20 most disabling medical conditions. This article focuses on the diagnosis and treatment of the primary headache disorders, with special emphasis on migraine, the headache most likely to bring patients to physicians and pharmacists. This review begins with the warning signs of the ominous headache, which, although rare, can herald a life-threatening condition. Clinical characteristics of the primary headache types, migraine, tension-type headache, and cluster headache, are described. Although many individuals believe their headaches are “sinus,” or “stress or tension-induced,” most of the characteristics of these types of headaches actually meet International Headache Society criteria for migraine. Treatments of primary headaches, including acute therapies, abortive agents, and prophylactic medications, are uniquely specific for each headache syndrome. Chronic daily headache patients compose only 4% of the population yet make up the largest percentage of patients who seek treatment at specialty headache centers. Medication-overuse headache, the syndrome in which medications taken for the relief of headache actually foster future headaches, offers a particular challenge to health care providers, as does narcotic use in headache therapy. Complementary and alternative treatments proven efficacious in the treatment of primary headache are also described.

Central Sensitization Theory of Migraine: Clinical Implications

The clinical science of migraine headache continues to evolve. Theories of the pathophysiology of migraine have progressed from the early vascular basis of migraine to more complex current theories that emphasize the centrality of neuronal dysfunction. The most recently articulated theory of migraine is the central sensitization hypothesis, which proposes that altered processing of sensory input in the brainstem, principally the trigeminal nucleus caudalis, could account for many of the temporal and symptomatic features of migraine, as well as its poor response to triptan therapy when such treatment is initiated hours after the onset of pain. Both preclinical and clinical data support the central sensitization theory. A critical clinical implication of this theory is that drugs that are capable of either aborting or arresting the process of central sensitization, most prominently dihydroergotamine, may have a unique role in the treatment of migraine. An additional, and highly practical, implication is based upon the finding that cutaneous allodynia-pain arising from innocuous stimulation of the skin, as in hair brushing or the application of cosmetics-is an easily identifiable marker of central sensitization. Thus, the presence or absence of cutaneous allodynia can be integrated into the routine clinical assessment of migraine and utilized as a determinant of treatment. Future basic and clinical research on central sensitization is likely to be of ongoing importance to the field.

Repetitive dihydroergotamine nasal spray for treatment of refractory headaches: an open-label pilot study

OBJECTIVE

To evaluate the safety and efficacy of a repetitive intranasal (IN) dihydroergotamine (DHE) burst protocol for treatment of refractory headaches.

RESEARCH DESIGN AND METHODS

Patients with refractory headaches were enrolled in a prospective, open-label, pilot study. Patients were instructed to self-administer IN DHE every 8 hours for 3 days; each IN DHE dose consisted of one 0.5-mg spray in each nostril that was repeated 15 minutes later, for a total of 2.0 mg DHE per dose. Follow-up visits were scheduled approximately 3 weeks later.

MAIN OUTCOME MEASURES

Efficacy and safety measurements were collected during patient interviews. Primary efficacy measures were the change in headache frequency, duration, and severity (rated from 0 [none] to 5 [extremely severe]) between the initial and follow-up visits. Safety was assessed at the follow-up visits through the occurrence of adverse events (AEs).

RESULTS

Twenty-six patients were enrolled in the study. Follow-up visits were completed by 24 patients whose mean headache frequency at study entry was 6.6 d/wk. The IN DHE burst protocol was associated with significant mean decreases in headache frequency (2.6 d/wk, p < 0.001), duration (5.8 hours, p = 0.03), and severity (1.2 units, p < 0.001) between study entry and the follow-up visit. One patient discontinued IN DHE use early because of an AE (nasal stuffiness); two additional patients each reported one AE (fatigue and increased headache) that was attributed to IN DHE.

CONCLUSIONS

The results of this pilot study suggest that the IN DHE burst protocol may be an effective and safe treatment for refractory headaches; interpretation of these results is limited by the open-label, uncontrolled design and the small number of patients. The development of a double-blind, placebo-controlled study to further evaluate this treatment regimen is warranted.

Intranasal medications for the treatment of migraine and cluster headache

Intranasal medications for the treatment of headache have recently received increased attention. This paper reviews intranasal formulations of a variety of available medications (dihydroergotamine mesylate [dihydroergotamine mesilate], sumatriptan, zolmitriptan, butorphanol, capsaicin and lidocaine [lignocaine]) and one experimental medication (civamide, a cis-isomer of capsaicin) for the treatment of migraine and cluster headache. Although the efficacy of intranasal agents varies with the product used, intranasal delivery may be both convenient and more effective than other modes of drug delivery for a variety of reasons: (i) intranasal administration bypasses small bowel gastrointestinal tract absorption, which is often significantly delayed during the acute phase of a migraine attack; (ii) nauseated patients may prefer non-oral formulations as they decrease the chance of vomiting and are more rapidly effective; (iii) intranasal administration causes no pain or injection site reaction and is easier and more convenient to administer than injection or suppository and so may be used earlier in a migraine attack, resulting in better efficacy; (iv) intranasal medication produces the same number or fewer adverse events than injections; and (v) intranasal formulations offer a more rapid onset of action than oral medications, for some of the above reasons and, as such, may be more useful in patients with cluster headache, although this needs to be verified. However, it is important to emphasise that a preference study showed that most patients prefer oral tablets to an intranasal formulation. Also, some nasal preparations have significant adverse effects or are not well absorbed and therefore do not work consistently; others are more challenging to administer as a result of their delivery apparatus. Nevertheless, it is our opinion that nasal preparations increase therapeutic options and may result in faster response times and better efficacy than oral formulations and better patient satisfaction than injectable preparations.

Cost Considerations of Acute Migraine Treatment

OBJECTIVE

To provide medication price data and cost-reducing strategies for the acute treatment of migraine.

METHODS

Retail prices for common acute care medications were found at http://www.drugstore.com. Cost-reduction tactics were obtained from literature searches and clinical experience.

RESULTS

Several strategies can reduce cost without sacrificing treatment outcome. In mild to moderate migraine, low-priced nonsteroidal anti-inflammatory drugs can be used as first-line medications due to their proven efficacy and favorable tolerability. For patients with more severe migraine, implementing a stratified care approach-using migraine-specific medications early in acute treatment-is cost-effective for most patients. Stratified care not only improves outcome and decreases disability, but also reduces cost. Pill splitting and early administration of triptans within an attack enhance their value. Supplying rescue medications, such as opioids, sedatives, and phenothiazines, can prevent emergency department visits. Minimizing multiple dosing of triptans and reducing utilization of expensive health care resources are key factors in reducing the cost of effective migraine treatment. An important affordability factor for patients with co-payments is the number of triptan pills per package. Sumatriptan, naratriptan, and frovatriptan each contain 9 tablets per package, while most other triptan packages contain 6. Current triptan retail prices (per unit) include: Amerge 1 and 2.5 mg, 17.78 dollars; Axert 6.25 and 12.5 mg, 16.31 dollars; Frova 2.5 mg, 13.89 dollars; Imitrex 50 mg, 14.96 dollars; Imitrex 100 mg, 14.41 dollars; Imitrex Nasal Spray 20 mg, 21.61 dollars; Imitrex SQ 6 mg, 50.26 dollars; Maxalt 5 and 10 mg, 15 dollars; Maxalt-MLT 5 and 10 mg, 15 dollars; Relpax 40 mg, 13.58 dollars; Zomig 2.5 mg, 13.67 dollars; Zomig 5 mg, 15.89 dollars; Zomig-ZMT 2.5 mg, 13.67 dollars; and Zomig-ZMT 5 mg, 15.89 dollars.

CONCLUSIONS

Practitioners can optimize the use of health care dollars without compromising quality of care through awareness of cost-saving treatment strategies, as well as price variations among medications.

Newer formulations of the triptans: advances in migraine management

Migraine is a common, frequently incapacitating, headache disorder that imposes a substantial burden on both the individual patient and society. The last two decades have witnessed an explosion in our understanding of the pathophysiology of migraine, and in our development of an efficacious and diverse therapeutic armamentarium. There are several routes of drug administration available to patients with migraine. All the serotonin 5-HT(1B/1D) receptor agonists (triptans) are available as oral tablets (sumatriptan, rizatriptan, zolmitriptan, naratriptan, almotriptan, frovatriptan and eletriptan). Only sumatriptan is available as a subcutaneous injection. Some triptans are also available via newer routes of administration, including orally disintegrating tablets (rizatriptan and zolmitriptan), rectal suppositories (sumatriptan) and intranasal sprays (sumatriptan and zolmitriptan). Oral disintegrating tablets and other non-oral triptan routes (subcutaneous, intranasal, rectal) are a useful alternative to conventional oral tablets for patients who have difficulty swallowing pills or prefer not to do so, and for patients whose nausea and/or vomiting precludes swallowing tablets and/or makes the likelihood of complete absorption unpredictable. This is important because epidemiological studies in migraine reveal that the vast majority of patients (>90%) have experienced nausea during a migraine attack and more than 50% have nausea with the majority of attacks. Similarly, most (almost 70%) have vomited at some time during an attack and of these patients, almost one-third vomit in the majority of attacks. The newer formulations, rapidly dissolving tablets and intranasal sprays, afford patients the opportunity to use abortive therapy without the need for liquids, at anytime and anywhere, at the onset of a migraine attack. Furthermore, the intranasal sprays are absorbed rapidly and have a prompt onset of action allowing for significant pain free rates versus placebo as early as 15 minutes post administration. The ability to administer treatment early in a migraine attack and have a rapid onset of action is particularly important in acute migraine treatment in order to prevent the development of central sensitisation. While many patients and physicians choose conventional oral tablets because of familiarity and ease of administration, the newer formulations, oral disintegrating tablets and intranasal sprays, should be given consideration as first-line agents in selected patients.

Placebo adverse events in headache trials: headache as an adverse event of placebo

We analysed the adverse events of placebo in acute and preventive randomized, double-blind, placebo-controlled studies for migraine treatment. Fifty-seven trials (oral triptans, non-steroidal anti-inflammatory drugs, nasal ergot alkaloids and preventive agents) were included. From 10 to 30% of subjects reported adverse events after placebo. Most common were features associated with a migraine attack, such as nausea, phono- and photophobia. Other frequent complaints resembled those of the active drug (e.g. chest pressure in triptan trials). A third group of adverse events appeared to be coincidental (e.g. sleep disturbance). Adverse events following placebo are probably related to the drug under study and the symptomatology of migraine; some have no obvious explanation.

Ergotamine and dihydroergotamine: history, pharmacology, and efficacy

Ergotamine and dihydroergotamine share structural similarities with the adrenergic, dopaminergic, and serotonergic neurotransmitters. As a result, they have wide-ranging effects on the physiologic processes that they mediate. Ergotamine and dihydroergotamine are highly potent at the 5-HT1B and 5-HT1D antimigraine receptors and, as a consequence, the plasma concentrations that are necessary to produce the appropriate therapeutic and physiologic effects are very low. The broad spectrum of activity at other monoamine receptors is responsible for their side effect profile (dysphoria, nausea, emesis, unnecessary vascular effects). Both ergotamine and dihydroergotamine have sustained vasoconstrictor actions. In acute migraine treatment, their mechanisms of action involve constricting the pain-producing intracranial extracerebral blood vessels at the 5-HT1B receptors and inhibiting the trigeminal neurotransmission at the peripheral and central 5-HT1D receptors. The scientific evidence for efficacy is stronger for dihydroergotamine than for ergotamine. Their wide use is based on long-term experience.

Ergotamine and dihydroergotamine: a review

The ergot alkaloids were the first specific antimigraine therapy available. However, with the advent of the triptans, their use in the treatment of migraine has declined and their role has become less clear. This review discusses the pharmacology, efficacy, and safety of the ergots. In randomized clinical trials, oral ergotamine was found to be superior to placebo, but inferior to 100 mg of oral sumatriptan. In contrast, rectal ergotamine was found to have higher efficacy (73% headache relief) than rectal sumatriptan (63% headache relief). Intranasal dihydroergotamine was found to be superior to placebo, but less effective than subcutaneous and intranasal sumatriptan. Ergotamine is still widely used in some countries for the treatment of severe migraine attacks. It is generally regarded as a safe and useful drug if prescribed for infrequent use, in the correct dose, and in the absence of contraindications; however, safer and more effective options do exist in the triptans. In patients with status migrainous and patients with frequent headache recurrence, ergotamine is still probably useful.

Practical approaches to migraine management

Migraine is a recurrent clinical syndrome characterised by combinations of neurological, gastrointestinal and autonomic manifestations. The exact pathophysiological disturbances that occur with migraine have yet to be elucidated; however, cervico-trigemino-vascular dysfunctions appear to be the primary cause. Despite advances in the understanding of the pathophysiology of migraine and new effective treatment options, migraine remains an under-diagnosed, under-treated and poorly treated health condition. Most patients will unsuccessfully attempt to treat their headaches with over-the-counter medications. Few well designed, placebo-controlled studies are available to guide physicians in medication selection. Recently published evidence-based guidelines advocate migraine-specific drugs, such as serotonin 5-HT(1B/1D) agonists (the 'triptans') and dihydroergotamine mesylate, for patients experiencing moderate to severe migraine attacks. Additional headache attack therapy options include other ergotamine derivatives, phenothiazines, nonsteroidal anti-inflammatory agents and opioids. Preventative medication therapy is indicated for patients experiencing frequent and/or refractory attacks.

Pharmacokinetics, pharmacodynamics, and safety of the 5-HT(1B/1D) agonist eletriptan following intravenous and oral administration

Four separate studies were conducted to examine the safety, tolerability, pharmacokinetics (PK), and pharmacodynamics (PD) of eletriptan, a 5-HT(1B/1D) receptor agonist being developed for the treatment of migraines, after oral and intravenous administration. Fifty-five males received oral (1.5-30 mg or 30-120 mg) or intravenous (1.67-50 microg/kg or 50-102 microg/kg) eletriptan in four double- and single-blind, placebo-controlled, ascending-dose crossover studies. The maximum plasma concentration (Cmax) and area under the concentration curve (AUC) appeared linear over all dose ranges, with an apparent terminal half-life of 4 to 5 hours. Clearance and volume of distribution remained constant with dose. The time to first occurrence of Cmax (tmax) for oral eletriptan was approximately 1 hour and was unaffected by dose. Comparison of AUC values suggested an absolute bioavailability of approximately 50%. A linear PK/PD model, fitted to the data, predicted small, transient elevations in diastolic blood pressure following eletriptan doses > or = 60 mg. These effects were considered unlikely to be clinically significant. Eletriptan was well tolerated, and treatment-related adverse events were mild to moderate and transient. These PK properties should result in eletriptan having a rapid onset and sustained duration of action in terms of migraine efficacy.

Post-traumatic Headache

Headache is the most common symptom after closed head injury, persisting for more than 2 months in 60% of patients. Rarely does headache occur in isolation. Cervical pain is a frequent accompaniment. Post-traumatic headache is often one of several symptoms of the postconcussive syndrome, and therefore may be accompanied by additional cognitive, behavioral, and somatic problems. Acute post-traumatic headaches may begin at the time of injury and continue for up to 2 months post-injury. Although onset proximate to the time of injury is most common, any new headache type occurring within this period of time is referred to as an acute post-traumatic headache. If such headaches persist beyond the first two months post-injury, they are subsequently referred to as chronic post-traumatic headaches. Over time, post-traumatic headaches may take on a pattern of daily occurrence. If aggressive treatment is initiated early, posttraumatic headache is less likely to become a permanent problem. Once "windup" of post-traumatic headaches occurs, the cycle of ongoing headaches is more difficult to interrupt. The mechanism of post-traumatic headache is poorly understood. Trauma-induced headaches are usually heterogeneous in nature, often including both tension-type pain and intermittent migraine-like attacks. Rebound-headaches may develop from overuse of analgesic medications, and the occurrence of such may complicate significantly the diagnosis of post-traumatic headache. Adequate treatment typically requires both "peripheral" and "central" measures. Understanding the general principles of treatment, especially appropriate use of preventive and abortive medications, will most usefully guide treatment. There is scant literature with which to direct treatment selection for post-traumatic headache. Consequently, treatments for post-traumatic headache are based on those prescribed for phenomenologically similar but etiologically distinct headache disorders. Delayed recovery from post-traumatic headache may be a result of inadequately aggressive or ineffective treatment, overuse of analgesic medications resulting in analgesia rebound phenomena, or comorbid psychiatric disorders (eg, post-traumatic stress disorder, insomnia, substance abuse, depression, or anxiety).

Efficacy of intravenous magnesium sulfate in the treatment of acute migraine attacks

OBJECTIVE

To study the efficacy and tolerability of 1 g of intravenous magnesium sulfate as acute treatment of moderate or severe migraine attacks.

BACKGROUND

Migraine is a common disorder in which not only the pain but also the accompanying symptoms such as nausea and vomiting reduce activity and productivity of sufferers. Many drugs used for the treatment of acute migraine attacks have many side effects, are not well tolerated, are ineffective in some patients, or cannot be used during pregnancy or in patients with ischemic heart disease. Magnesium deficiency has been proposed to play a role in the pathophysiology of migraine, and recently treatment of migraine with magnesium has gained considerable interest.

METHODS

This was a randomized, single-blind, placebo-controlled trial including 30 patients with moderate or severe migraine attacks. Fifteen patients received 1 g intravenous magnesium sulfate given over 15 minutes. The next 15 patients received 10 mL of 0.9% saline intravenously. Those in the placebo group with persisting complaints of pain or nausea and vomiting after 30 minutes also received 1 g magnesium sulfate intravenously over 15 minutes. The patients were assessed immediately after treatment, and then 30 minutes and 2 hours later. Intensity of pain, accompanying symptoms, and side effects were noted.

RESULTS

All patients in the treatment group responded to treatment with magnesium sulfate. The pain disappeared in 13 patients (86.6%); it was diminished in 2 patients (13.4%); and in all 15 patients (100%), accompanying symptoms disappeared. In the placebo group, a decrease in pain severity but persisting nausea, irritability, and photophobia were noted in 1 patient (6.6%). Accompanying symptoms disappeared in 3 patients (20%) 30 minutes after placebo administration. All patients initially receiving placebo were subsequently given magnesium sulfate. All of these patients responded to magnesium sulfate. In 14 patients (93.3%), the attack ended; in 1 patient (6.6%), pain intensity decreased; and in all 15 patients (100%), accompanying symptoms disappeared. Both the response rate (100% for magnesium sulfate and 7% for placebo) and the pain-free rate (87% for magnesium sulfate and 0% for placebo) showed that magnesium sulfate was superior to placebo. Twenty-six patients (86.6%) had mild side effects which did not necessitate discontinuing treatment during magnesium sulfate administration.

CONCLUSION

Our results show that 1 g intravenous magnesium sulfate is an efficient, safe, and well-tolerated drug in the treatment of migraine attacks. It is possible that magnesium sulfate could be used in a broader spectrum of patients than other drugs commonly used for attack treatment. In view of these results, the effect of magnesium sulfate in acute migraine should be examined in large-scale studies.

Ergotamine, dihydroergotamine: current uses and problems

In randomized clinical trials oral ergotamine was found superior to placebo but inferior to oral sumatriptan 100mg. In contrast rectal ergotamine was found to have higher efficacy (73% headache relief) than rectal sumatriptan (63% headache relief). Intranasal dihydroergotamine (DHE) was found superior to placebo but less effective than subcutaneous and intranasal sumatriptan. In general, the use of the more specific drugs, the triptans, causing less adverse events and being more effective, is preferable to the use of the ergotamine in the acute treatment of migraine. If ergotamine is to be used the rectal route is preferable. The rectal dose of ergotamine should be tailored to the individual patient. The intranasal dose of DHE , between 1 and 2 mg, should also be tailored to the individual patient. In order to avoid drug-induced headache ergotamine and DHE should not be used daily.

Migraine: pharmacotherapy in the emergency department

Migraine can be a disabling condition for the sufferer. For the small number of patients for whom home therapy fails and who seek treatment in an emergency department, several therapeutic options are available. I review the evidence regarding the effectiveness and safety of the following therapies: the phenothiazines, lignocaine (lidocaine), ketorolac, the ergot alkaloids, metoclopramide hydrochloride, the "triptans," haloperidol, pethidine (meperidine hydrochloride), and magnesium sulfate. Based on available evidence, the most effective agents seem to be prochlorperazine, chlorpromazine and sumatriptan, each of which has achieved greater than 70% efficacy in several studies.

Emergency department management of pediatric migraine

Migraine is a common pediatric emergency department problem. Since its pathophysiology is unclear and possibly multifactorial, a single treatment strategy is unlikely to be successful for all patients. A specific treatment that has been successful for a particular patient should be strongly considered. Otherwise, it is best to start with simple therapies such as acetaminophen, aspirin, or an NSAID if not already tried at home. For patients requiring more specific therapy, reasonable choices would be dihydroergotamine or a dopamine antagonist such as prochlorperazine. There are several newer agents studied in adults with examples being sumatriptan and naratriptan. These probably have a role in the adolescent and should be considered in the younger age group when other therapies have failed. When the headache has been prolonged, dexamethasone may be useful in decreasing inflammation and relieving pain. As illustrated in many of the above studies, monotherapy is often inadequate in achieving complete relief of headache pain in all patients. Most of the drugs discussed here address only one of the three etiologies thought to be involved in migraine pathogenesis, namely; the dopaminergic system. the serotonin system or inflammation. Presumably, therapy directed toward more than one of these etiologies at the same time may be more effective (11).

Determination of dihydroergotamine in human plasma by high-performance liquid chromatography with fluorescence detection

Dihydroergotamine, a 5-hydroxytryptamine antagonist, is used for the treatment of vascular headaches. A high-performance liquid chromatography assay with fluorescence detection is described for the determination of dihydroergotamine in plasma. The assay was validated over the concentration range 0.1-10 ng/ml plasma and applied to the analysis of plasma samples from subjects treated intramuscularly and intranasally with 2 mg of dihydroergotamine.

Migraine: a comprehensive review of new treatment options

Headaches are among the most common complaints reported to health care professionals and are classified by the International Headache Society as migraine, tension-type, or cluster, with additional subtypes. Classification and etiology of headache should be determined after thorough review of the patient's history. Once diagnosed, migraine can be treated by preventive or abortive measures. Recent developments add new options, including availability of drugs for intranasal administration (sumatriptan, dihydroergotamine) and 5-HT1B/1D agonists (rizatriptan, zolmitriptan, naratriptan, eletriptan). Although placebo-controlled trials are available, few comparative clinical trials of these agents have been conducted; however, important pharmacologic, pharmacokinetic, and clinical differences exist among the drugs.

Symptomatic pharmacotherapy of migraine

This review summarizes data on the effectiveness of various symptomatic migraine pharmacotherapies and makes recommendations for treatment. A wide variety of agents are available for the symptomatic treatment of migraine headache, including over-the-counter analgesics, nonsteroidal anti-inflammatory drugs (NSAIDs), combination products, opiates, ergot alkaloids, corticosteroids, dopamine antagonists, and triptans. In the stepped-care approach, simple analgesics and NSAIDs are the recommended first step for the treatment of mild-to-moderate migraine headaches. Patients who do not respond to first-step treatments may be given ergots, combination products, dopamine antagonists, or triptans as the second step. Corticosteroids or opiates may be used as rescue treatment in patients who do not respond to second-step treatment. A stratified approach to care individualizes treatment based on the severity of the headache and other patient-specific factors. In a stratified approach, dihydroergotamine or triptans may be the first-step treatment for patients who present with a history of severe migraines that have responded poorly to previous treatments. Sumatriptan was the first triptan approved for the symptomatic treatment of migraine headache; newer triptans include zolmitriptan, naratriptan, and rizatriptan. Since sumatriptan is rapidly absorbed by the subcutaneous route, its time to onset of effect is shortest. Among triptan drugs that are administered orally, the relative time to onset may be shorter with rizatriptan than sumatriptan. Naratriptan has a longer time to onset but is associated with a lower rate of migraine recurrence than other triptans. graine headache, ergot alkaloids, triptans,

Characterization of lidocaine metabolism by rat nasal microsomes: implications for nasal drug delivery

Lidocaine has been recently approved for use as an intranasal spray in the treatment of migraine. In this study, we investigated the metabolism of lidocaine to its primary metabolite monoethylglycine xylidide (MEGX), by rat nasal olfactory and respiratory microsomes. The metabolic parameters were compared with metabolism employing rat and human hepatic microsomes. The olfactory and respiratory microsomes both exhibited considerable activity for conversion of lidocaine to MEGX in comparison with the activity in the hepatic tissues. The rat olfactory microsomes had a markedly higher affinity than the rat hepatic or respiratory microsomes. However, the turnover rate was only about one-half that of rat liver. Employing Western immunoblotting we investigated the presence of cytochrome P450s (CYPs) 1A2, 3A2, 2B1 and 2C11 in rat nasal tissues; these isozymes are known to partcipated in the metabolism of lidocaine in rat liver. These isozymes were found to be present in significant amounts in both the nasal olfactory and respiratory tissue; this is the first known report of the presence of CYP2C11 in nasal mucosae. Our studies underscore the importance of CYP-mediated drug metabolism in nasal tissues. The effect of this 'nasal first-pass' should be weighed carefully while considering the fate and the bioavailability of drugs delivered via the intranasal route.

Canadian Association of Emergency Physicians Guidelines for the acute management of migraine headache

The aim of this article is to provide an evidence-based guideline on the management of acute migraine headaches in the Emergency Department setting. After a Medline search that covered 1965 to the present, all randomized controlled trials were reviewed. Recommendations as to the efficacy of abortive anti-migraine medications were based on the Canadian Medical Association's Guideline for Guidelines. Classes of medications that are discussed include: dopamine antagonists, serotonin agonists, opioids, local anesthetics, non-steroidal anti-inflammatory agents, and steroids. The recommendations are limited to discussing the efficacy of specific medications, adverse effects to be expected, as well as associated headache rates after discharge. Specific recommendations as to which medication might offer a superior treatment have not been proposed due to lack of proper comparative trials as well as lack of information on headache and quality of life after discharge from the Emergency Department.

Pharmacologic Treatment of Migraine

The vascular theory of migraine proposed by Wolff, attributing migrainous symptoms to paroxysmal constriction and dilation of the cranial vasculature, held sway for over four decades and even now remains embraced by many clinicians and the lay public. Recent investigations, however, suggest that this proposed mechanism is untenable; although changes in blood vessel caliber and blood flow do occur in some patients during some attacks, they are not required for the production of migrainous symptoms and appear to be largely epiphenomena, occurring subsequent (and consequent) to another primary process. Evidence is mounting that migraine may result from a pathologic alteration of neurotransmission within the brain stem and trigeminovascular system, and one of the neurotransmitters primarily involved is serotonin. This has led to an explosion of interest in therapeutic agents which influence serotoninergic receptors, and the astounding success enjoyed by the first of these agents to be utilized clinically (sumatriptan and dihydroergotamine) and their offspring suggests that our understanding of this common and vexing problem will increase and be paralleled by the identification of yet more specific and effective treatment intervention.