Aspirin in the treatment of acute migraine attacks

Progress in Traditional Chinese Medicine for the Treatment of Migraine

Migraine is a recurrent disease with complex pathogenesis and is difficult to cure. At present, commercially available western migraine drugs are prone to generate side effects while treating the disease. Traditional Chinese medicine (TCM) avoids side effects via treatment with the principles of “treating both symptoms and root causes”, “overall adjustment”, and “treatment based on syndrome differentiation”. Three strategies of drug treatment were developed based on the syndromes, i.e., removing stasis, calming liver Yang, and reinforcing deficiency. Prescriptions of removing stasis mostly contain Chuanxiong rhizome (Chuan Xiong) to remove blood stasis by promoting blood circulation and improve properties of hemorheology, and Da Chuan Xiong Formula (DCXF) is a traditional prescription widely used in clinical practice. Prescriptions of calming liver Yang usually take Ramulus Uncariae cum Uncis (Gou Teng) as the main herb, which can calm the liver Yang via improving vasomotor function, and Tian Ma Gou Teng Decoction (TMGTD) is the representative drug. For reinforcing deficiency, Chinese doctors frequently utilize Angelica Sinensis (Dang Gui) and Astragali Radix (Huang Qi) to nourish blood and Qi in order to improve the weak state of human body; Dang Gui Bu Xue Decoction (DGBXD) is the commonly used prescription. These strategies not only treat the symptoms of diseases but also their root causes, and with the features of multiple targets, in multiple ways. Therefore, TCM prescriptions have obvious advantages in the treatment of chronic diseases such as migraine. In this review, we provided an overview of the pathogenesis of migraine and the function of representative TCM preparations in therapy of migraine as well as the mechanism of action according to effective researches, in order to provide reference and clue for further researches.

Influence of Differing Analgesic Formulations of Aspirin on Pharmacokinetic Parameters

Aspirin has been used therapeutically for over 100 years. As the originator and an important marketer of aspirin-containing products, Bayer's clinical trial database contains numerous reports of the pharmacokinetics of various aspirin formulations. These include evaluations of plain tablets, effervescent tablets, granules, chewable tablets, and fast-release tablets. This publication seeks to expand upon the available pharmacokinetic information concerning aspirin formulations. In the pre-systemic circulation, acetylsalicylic acid (ASA) is rapidly converted into its main active metabolite, salicylic acid (SA). Therefore, both substances are measured in plasma and reported in the results. The 500 mg strength of each formulation was chosen for analysis as this is the most commonly used for analgesia. A total of 22 studies were included in the analysis. All formulations of 500 mg aspirin result in comparable plasma exposure to ASA and SA as evidenced by AUC. Tablets and dry granules provide a consistently lower Cmax compared to effervescent, granules in suspension and fast release tablets. Effervescent tablets, fast release tablets, and granules in suspension provide a consistently lower median Tmax compared to dry granules and tablets for both ASA and SA. This report reinforces the importance of formulation differences and their impact on pharmacokinetic parameters.

Review of dose-response curves for acute antimigraine drugs: triptans, 5-HT1F agonists and CGRP antagonists

INTRODUCTION

Dose-response curves for efficacy and tolerability are the important determinants for the choice of doses of acute migraine drugs.

AREAS COVERED

Dose-response curves for the efficacy of seven triptans (5-HT1B/1D receptor agonists), a 5-HT1F receptor agonist (lasmiditan) and four oral calcitonin-gene related peptide receptor antagonists (telcagepant, MK-3207, BI 44370 TA and BMS-927711) in placebo-controlled trials were reviewed. In addition, dose-response curves for adverse events (AEs) were reviewed.

EXPERT OPINION

For most triptans, the dose-response curve for efficacy is flat, whereas AEs often increase with increasing doses. The two other groups of drugs also have flat dose-response curves for efficacy. Overall, the triptans still have the most favorable efficacy-tolerability profile. Current acute antimigraine drugs do not fulfill the expectations of the patients, and thus, there are many unmet needs. Although upcoming drugs may not be superior to triptans, migraine patients will potentially benefit greatly from these, especially patients who are triptan non-responders and patients with cardiovascular disease.

Calcitonin gene-related peptide (CGRP): a new target for migraine

Migraine is a neurological disorder that manifests as a debilitating headache associated with altered sensory perception. The neuropeptide calcitonin gene-related peptide (CGRP) is now firmly established as a key player in migraine. Clinical trials carried out during the past decade have proved that CGRP receptor antagonists are effective for treating migraine, and antibodies to the receptor and CGRP are currently under investigation. Despite this progress in the clinical arena, the mechanisms by which CGRP triggers migraine remain uncertain. This review discusses mechanisms whereby CGRP enhances sensitivity to sensory input at multiple levels in both the periphery and central nervous system. Future studies on epistatic and epigenetic regulators of CGRP actions are expected to shed further light on CGRP actions in migraine. In conclusion, targeting CGRP represents an approachable therapeutic strategy for migraine.

Central effects of acetylsalicylic acid on trigeminal-nociceptive stimuli

BACKGROUND

Acetylsalicylic acid is one of the most used analgesics to treat an acute migraine attack. Next to the inhibitory effects on peripheral prostaglandin synthesis, central mechanisms of action have also been discussed.

METHODS

Using a standardized model for trigeminal-nociceptive stimulation during fMRI scanning, we investigated the effect of acetylsalicylic acid on acute pain compared to saline in 22 healthy volunteers in a double-blind within-subject design. Painful stimulation was applied using gaseous ammonia and presented in a pseudo-randomized order with several control stimuli. All participants were instructed to rate the intensity and unpleasantness of every stimulus on a VAS scale. Based on previous results, we hypothesized to find an effect of ASA on central pain processing structures like the ACC, SI and SII as well as the trigeminal nuclei and the hypothalamus.

RESULTS

Even though we did not find any differences in pain ratings between saline and ASA, we observed decreased BOLD signal changes in response to trigemino-nociceptive stimulation in the ACC and SII after administration of ASA compared to saline. This finding is in line with earlier imaging results investigating the effect of ASA on acute pain. Contrary to earlier findings from animal studies, we could not find an effect of ASA on the trigeminal nuclei in the brainstem or within the hypothalamic area.

CONCLUSION

Taken together our study replicates earlier findings of an attenuating effect of ASA on pain processing structures, which adds further evidence to a possibly central mechanism of action of ASA.

Reactive oxygen species induce procalcitonin expression in trigeminal ganglia glia

OBJECTIVE

To examine calcitonin gene-related peptide (CGRP) gene expression under inflammatory conditions using trigeminal ganglia organ cultures as an experimental system. These cultures have increased proinflammatory signaling that may mimic neurogenic inflammation in the migraine state.

BACKGROUND

The trigeminal nerve sends peripheral pain signals to the central nervous system during migraine. Understanding the dynamic processes that occur within the trigeminal nerve and ganglion may provide insights into events that contribute to migraine pain. A neuropeptide of particular interest is CGRP, which can be elevated and play a causal role in migraine. However, most studies have overlooked a second splice product of the Calca gene that encodes calcitonin (CT), a peptide hormone involved in calcium homeostasis. Importantly, a precursor form of CT called procalcitonin (proCT) can act as a partial agonist at the CGRP receptor and elevated proCT has recently been reported during migraine.

METHODS

We used a trigeminal ganglion whole organ explant model, which has previously been demonstrated to induce pro-inflammatory agents in vitro. Quantitative polymerase chain reaction and immunohistochemistry were used to evaluate changes in messenger ribonucleic acid (mRNA) and protein levels of CGRP and proCT.

RESULTS

Whole mouse trigeminal ganglia cultured for 24 hours showed a 10-fold increase in CT mRNA, with no change in CGRP mRNA. A similar effect was observed in ganglia from adult rats. ProCT immunoreactivity was localized in glial cells. Cutting the tissue blunted the increase in CT, suggesting that induction required the close environment of the intact ganglia. Consistent with this prediction, there were increased reactive oxygen species in the ganglia, and the elevated CT mRNA was reduced by antioxidant treatment. Surprisingly, reactive oxygen species were increased in neurons, not glia.

CONCLUSIONS

These results demonstrate that reactive oxygen species can activate proCT expression from the CGRP gene in trigeminal glia by a paracrine regulatory mechanism. We propose that this glial recruitment pathway may occur following cortical spreading depression and neurogenic inflammation to increase CGRP nociceptive actions in migraine.

CGRP and migraine: could PACAP play a role too?

Migraine is a debilitating neurological disorder that affects about 12% of the population. In the past decade, the role of the neuropeptide calcitonin gene-related peptide (CGRP) in migraine has been firmly established by clinical studies. CGRP administration can trigger migraines, and CGRP receptor antagonists ameliorate migraine. In this review, we will describe multifunctional activities of CGRP that could potentially contribute to migraine. These include roles in light aversion, neurogenic inflammation, peripheral and central sensitization of nociceptive pathways, cortical spreading depression, and regulation of nitric oxide production. Yet clearly there will be many other contributing genes that could act in concert with CGRP. One candidate is pituitary adenylate cyclase-activating peptide (PACAP), which shares some of the same actions as CGRP, including the ability to induce migraine in migraineurs and light aversive behavior in rodents. Interestingly, both CGRP and PACAP act on receptors that share an accessory subunit called receptor activity modifying protein-1 (RAMP1). Thus, comparisons between the actions of these two migraine-inducing neuropeptides, CGRP and PACAP, may provide new insights into migraine pathophysiology.

Aspirin with or without an antiemetic for acute migraine headaches in adults

BACKGROUND

This is an updated version of the original Cochrane review published in Issue 4, 2010 (Kirthi 2010). Migraine is a common, disabling condition and a burden for the individual, health services and society. Many sufferers choose not to, or are unable to, seek professional help and rely on over-the-counter analgesics. Co-therapy with an antiemetic should help to reduce nausea and vomiting commonly associated with migraine headaches.

OBJECTIVES

To determine the efficacy and tolerability of aspirin, alone or in combination with an antiemetic, compared to placebo and other active interventions in the treatment of acute migraine headaches in adults.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Oxford Pain Relief Database, ClinicalTrials.gov, and reference lists for studies through 10 March 2010 for the original review and to 31 January 2013 for the update.

SELECTION CRITERIA

We included randomised, double-blind, placebo-controlled or active-controlled studies, or both, using aspirin to treat a migraine headache episode, with at least 10 participants per treatment arm.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Numbers of participants achieving each outcome were used to calculate relative risk and numbers needed to treat (NNT) or harm (NNH) compared to placebo or other active treatment.

MAIN RESULTS

No new studies were found for this update. Thirteen studies (4222 participants) compared aspirin 900 mg or 1000 mg, alone or in combination with metoclopramide 10 mg, with placebo or other active comparators, mainly sumatriptan 50 mg or 100 mg. For all efficacy outcomes, all active treatments were superior to placebo, with NNTs of 8.1, 4.9 and 6.6 for 2-hour pain-free, 2-hour headache relief, and 24-hour headache relief with aspirin alone versus placebo, and 8.8, 3.3 and 6.2 with aspirin plus metoclopramide versus placebo. Sumatriptan 50 mg did not differ from aspirin alone for 2-hour pain-free and headache relief, while sumatriptan 100 mg was better than the combination of aspirin plus metoclopramide for 2-hour pain-free, but not headache relief; there were no data for 24-hour headache relief.Adverse events were mostly mild and transient, occurring slightly more often with aspirin than placebo.Additional metoclopramide significantly reduced nausea (P < 0.00006) and vomiting (P = 0.002) compared with aspirin alone.

AUTHORS' CONCLUSIONS

We found no new studies since the last version of this review. Aspirin 1000 mg is an effective treatment for acute migraine headaches, similar to sumatriptan 50 mg or 100 mg. Addition of metoclopramide 10 mg improves relief of nausea and vomiting. Adverse events were mainly mild and transient, and were slightly more common with aspirin than placebo, but less common than with sumatriptan 100 mg.

Italian guidelines for primary headaches: 2012 revised version

The first edition of the Italian diagnostic and therapeutic guidelines for primary headaches in adults was published in J Headache Pain 2(Suppl. 1):105–190 (2001). Ten years later, the guideline committee of the Italian Society for the Study of Headaches (SISC) decided it was time to update therapeutic guidelines. A literature search was carried out on Medline database, and all articles on primary headache treatments in English, German, French and Italian published from February 2001 to December 2011 were taken into account. Only randomized controlled trials (RCT) and meta-analyses were analysed for each drug. If RCT were lacking, open studies and case series were also examined. According to the previous edition, four levels of recommendation were defined on the basis of levels of evidence, scientific strength of evidence and clinical effectiveness. Recommendations for symptomatic and prophylactic treatment of migraine and cluster headache were therefore revised with respect to previous 2001 guidelines and a section was dedicated to non-pharmacological treatment. This article reports a summary of the revised version published in extenso in an Italian version.

Evaluation of onset of pain relief from micronized aspirin in a dental pain model

A new formulation of a micronized acetylsalicylic acid swallowable tablet with an effervescent component (FR-aspirin) was evaluated in two independent studies using the dental impaction pain model. These clinical studies were performed to confirm the results of preclinical dissolution studies and human pharmacokinetic studies, which indicated an improved onset of analgesia without compromising duration of effect or safety. Study 1 evaluated a 650-mg dose of aspirin and Study 2 evaluated a 1,000-mg dose of aspirin. Both studies were double-blinded, parallel group and compared to regular aspirin (R-aspirin) and placebo. Speed of onset was measured by the double stopwatch method for time to both first perceptible relief and meaningful relief. In both studies, the FR-aspirin was significantly faster (p<0.038-0.001) than both R-aspirin and placebo for both onset measures. There were no significant differences between FR-aspirin and R-aspirin for peak or total effects and both treatments were significantly better than placebo. For first perceptible relief, FR-aspirin onset was 19.8 and 16.3 min for 650 mg and 1,000 mg, respectively, compared to 23.7 and 20.0 for R-aspirin. For meaningful relief, FR-aspirin onset was 48.9 and 49.4 min for 650 mg and 1,000 mg, respectively, compared to 119.2 and 99.2 for R-aspirin. These efficacy studies clearly demonstrate that the onset of analgesic efficacy is dramatically improved by adding an effervescent component and micronized active ingredient to the swallowable tablet aspirin formulation. The enhanced onset did not adversely impact either the peak effect or duration of effect or tolerability compared to regular aspirin.

Calcitonin gene-related peptide in migraine: intersection of peripheral inflammation and central modulation

Over the past two decades, a convergence of basic and clinical evidence has established the neuropeptide calcitonin-gene-related peptide (CGRP) as a key player in migraine. Although CGRP is a recognised neuromodulator of nociception, its mechanism of action in migraine remains elusive. In this review, we present evidence that led us to propose that CGRP is well poised to enhance neurotransmission in migraine by both peripheral and central mechanisms. In the periphery, it is thought that local release of CGRP from the nerve endings of meningeal nociceptors following their initial activation by cortical spreading depression is critical for the induction of vasodilation, plasma protein extravasation, neurogenic inflammation and the consequential sensitisation of meningeal nociceptors. Mechanistically, we propose that CGRP release can give rise to a positive-feedback loop involved in localised increased synthesis and release of CGRP from neurons and a CGRP-like peptide called procalcitonin from trigeminal ganglion glia. Within the brain, the wide distribution of CGRP and CGRP receptors provides numerous possible targets for CGRP to act as a neuromodulator.

Self-medication of migraine and tension-type headache: summary of the evidence-based recommendations of the Deutsche Migräne und Kopfschmerzgesellschaft (DMKG), the Deutsche Gesellschaft für Neurologie (DGN), the Österreichische Kopfschmerzgesellschaft (ÖKSG) and the Schweizerische Kopfwehgesellschaft (SKG)

The current evidence-based guideline on self-medication in migraine and tension-type headache of the German, Austrian and Swiss headache societies and the German Society of Neurology is addressed to physicians engaged in primary care as well as pharmacists and patients. The guideline is especially concerned with the description of the methodology used, the selection process of the literature used and which evidence the recommendations are based upon. The following recommendations about self-medication in migraine attacks can be made: The efficacy of the fixed-dose combination of acetaminophen, acetylsalicylic acid and caffeine and the monotherapies with ibuprofen or naratriptan or acetaminophen or phenazone are scientifically proven and recommended as first-line therapy. None of the substances used in self-medication in migraine prophylaxis can be seen as effective. Concerning the self-medication in tension-type headache, the following therapies can be recommended as first-line therapy: the fixed-dose combination of acetaminophen, acetylsalicylic acid and caffeine as well as the fixed combination of acetaminophen and caffeine as well as the monotherapies with ibuprofen or acetylsalicylic acid or diclofenac. The four scientific societies hope that this guideline will help to improve the treatment of headaches which largely is initiated by the patients themselves without any consultation with their physicians.

Aspirin with or without an antiemetic for acute migraine headaches in adults

BACKGROUND

Migraine is a common, disabling condition and a burden for the individual, health services and society. Many sufferers choose not to, or are unable to, seek professional help and rely on over-the-counter analgesics. Co-therapy with an antiemetic should help to reduce nausea and vomiting commonly associated with migraine headaches.

OBJECTIVES

To determine the efficacy and tolerability of aspirin, alone or in combination with an antiemetic, compared to placebo and other active interventions in the treatment of acute migraine headaches in adults.

SEARCH STRATEGY

We searched Cochrane CENTRAL, MEDLINE, EMBASE and the Oxford Pain Relief Database for studies through 10 March 2010.

SELECTION CRITERIA

We included randomised, double-blind, placebo- or active-controlled studies using aspirin to treat a discrete migraine headache episode, with at least 10 participants per treatment arm.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. Numbers of participants achieving each outcome were used to calculate relative risk and numbers needed to treat (NNT) or harm (NNH) compared to placebo or other active treatment.

MAIN RESULTS

Thirteen studies (4222 participants) compared aspirin 900 mg or 1000 mg, alone or in combination with metoclopramide 10 mg, with placebo or other active comparators, mainly sumatriptan 50 mg or 100 mg. For all efficacy outcomes, all active treatments were superior to placebo, with NNTs of 8.1, 4.9 and 6.6 for 2-hour pain-free, 2-hour headache relief, and 24-hour headache relief with aspirin alone versus placebo, and 8.8, 3.3 and 6.2 with aspirin plus metoclopramide versus placebo. Sumatriptan 50 mg did not differ from aspirin alone for 2-hour pain-free and headache relief, while sumatriptan 100 mg was better than the combination of aspirin plus metoclopramide for 2-hour pain-free, but not headache relief; there were no data for 24-hour headache relief.Associated symptoms of nausea, vomiting, photophobia and phonophobia were reduced with aspirin compared with placebo, with additional metoclopramide significantly reducing nausea (P < 0.00006) and vomiting (P = 0.002) compared with aspirin alone.Fewer participants needed rescue medication with aspirin than with placebo. Adverse events were mostly mild and transient, occurring slightly more often with aspirin than placebo.

AUTHORS' CONCLUSIONS

Aspirin 1000 mg is an effective treatment for acute migraine headaches, similar to sumatriptan 50 mg or 100 mg. Addition of metoclopramide 10 mg improves relief of nausea and vomiting. Adverse events were mainly mild and transient, and were slightly more common with aspirin than placebo, but less common than with sumatriptan 100 mg.

Sociodemographic differences in diagnosis and treatment of pediatric headache

The authors investigated the sociodemographic differences in receiving a headache diagnosis for pediatric health care visits using 2 nationally representative databases--the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey. For those visits involving a headache diagnosis, the authors explored 2 possible disparities in care--being diagnosed by a neurologist and being prescribed an evidence-based medication. A headache diagnosis was less common during visits for private insurance patients versus Medicaid patients. In addition, while a headache diagnosis was equally likely for visits by Caucasian American children versus African American children and children of other races, visits for the latter 2 groups were less likely to involve a headache diagnosis from a neurologist. Finally, only 37% of the headache visits involved a prescription of an evidence-based medication. The authors conclude that some sociodemographic disparities exist in pediatric headache care across the United States.

Demonstration of the analgesic efficacy and dose-response of acetylsalicylic acid with pseudoephedrine

To determine acute analgesia by acetylsalicylic acid (ASA) when combined with pseudoephedrine (PSE) in patients with upper respiratory tract infection (URTI), we used the sore throat pain model to measure single-dose effects of ASA 500 mg/PSE 30 mg, ASA 1000 mg/PSE 60 mg, and acetaminophen (APAP) 1000 mg/PSE 60 mg (serving as a positive control). Under double-blind, randomized, placebo-controlled conditions, 640 adult patients with confirmed acute pharyngitis and rhinosinusitis associated with URTI rated throat pain intensity and relief at intervals over 6 hours. Efficacy was demonstrated for both doses of ASA/PSE compared with placebo for all end points, including total pain relief and summed pain intensity differences, beginning at 20 minutes on both scales (all P < .05), and the efficacy of APAP/PSE compared with placebo was confirmed (P < .01). Greater differences in pain relief and intensity were also demonstrated between the higher and lower doses of ASA/PSE (P < .05), in particular, among 329 patients with severe pain, as well as between ASA 1000 mg/PSE 60 mg and APAP 1000 mg/PSE 60 mg (P < .05). No serious adverse events were reported. This study demonstrates that ASA is a well-tolerated and effective analgesic in 500- and 1000-mg doses when combined with pseudoephedrine.

Pharmacology

Headache treatment has been based primarily on experiences with non-specific drugs such as analgesics, non-steroidal anti-inflammatory drugs, or drugs that were originally developed to treat other diseases, such as beta-blockers and anticonvulsant medications. A better understanding of the basic pathophysiological mechanisms of migraine and other types of headache has led to the development over the past two decades of more target-specific drugs. Since activation of the trigeminovascular system and neurogenic inflammation are thought to play important roles in migraine pathophysiology, experimental studies modeling those events successfully predicted targets for selective development of pharmacological agents to treat migraine. Basically, there are two fundamental strategies for the treatment of migraine, abortive or preventive, based to a large degree on the frequency of attacks. The triptans, which exhibit potency towards selective serotonin (5-hydroxytryptamine, 5-HT) receptors expressed on trigeminal nerves, remain the most effective drugs for the abortive treatment of migraine. However, numerous preventive medications are currently available that modulate the excitability of the nervous system, particularly the cerebral cortex. In this chapter, the pharmacology of commercially available medications as well as drugs in development that prevent or abort headache attacks will be discussed.

Finding New Drug Targets for the Treatment of Migraine Attacks

No new preventive drugs specific to migraine have appeared for the last 20 years and existing acute therapies need improvement. Unfortunately, no animal models can predict the efficacy of new therapies for migraine. Because migraine attacks are fully reversible and can be aborted by therapy, the headache- or migraine-provoking property of naturally occurring signalling molecules can be tested in a human model. This model has predicted efficacy of nitric oxide synthase inhibition and calcitonin gene-related peptide receptor blockade. The pharmaceutical industry should pay more attention to human models, although methods are different from normal target validation.

Rapid oral transmucosal absorption of sumatriptan, and pharmacodynamics in acute migraine

OBJECTIVES

(1) To determine whether sumatriptan can be absorbed across the oral mucosa, and, if so; then (2) to describe its pharmacokinetics; and (3) to investigate whether there are pharmacodynamic correlates of such pharmacokinetics in patients experiencing migraine attacks.

METHODS

Two clinical trials. The first, in normal volunteers, compared the pharmacokinetic performance of a lingual spray (LS) formulation of sumatriptan (2 dose sizes, one of which in both the fed and fasted state) with an orthodox 50-mg sumatriptan tablet. The second clinical trial, in a patient population enriched by documenting suboptimal response to an initial 50-mg sumatriptan tablet, was a multiple-attack, crossover, fixed dose-order, open-label comparison of sumatriptan administered by LS (up to 3 different dose sizes) and a 100-mg sumatriptan tablet.

RESULTS

The LS formulations resulted in double-peaked time-plasma concentration curves that are consistent with absorption of sumatriptan across the oral mucosa. The first T(max) was usually about 10-15 minutes. In the enriched patient population, this corresponded with evidence of earlier efficacy for the LS in comparison with a 50-mg tablet; the lower dose size for the former was consistent with oral mucosal drug absorption, and evasion of first-pass metabolism.

CONCLUSIONS

The initial pharmacokinetics of LS approximate to those of a subcutaneous injection, albeit some fraction of these doses is also swallowed. These pharmacokinetics correspond with earlier effectiveness of LS in comparison with a 50-mg sumatriptan tablet, and at lower dose, in an enriched, relevant patient population. These initial studies support further development of this innovative formulation of sumatriptan and this new route of administration.

Over-the-counter triptans for migraine : what are the implications?

In 2006, the triptans sumatriptan 50mg and naratriptan 2.5mg were approved as over-the-counter (OTC) drugs in pharmacies in the UK and Germany, respectively. Both drugs have been used in a large number of patients with migraine and are considered to have good safety profiles. The implications of OTC triptan availability for clinical practice are that more migraine patients will use a triptan and will tend to medicate early when their headache is still mild, which should be beneficial. The problem with OTC access to triptans is medication overuse; therefore, patients should be warned of this and advised to use a triptan on fewer than 10 days per month. Pharmacists should be educated regarding migraine types and symptoms and on contraindications to triptans, so they are then able to discern the patients who should receive triptans and, as importantly, those who should not. The annual cost of migraine is euro27 billion in Europe, $US1.4 billion in the UK and $US16.6 billion in the US. By far the greatest opportunity for cost-savings comes from the potential to reduce costs associated with lost productivity from migraine. OTC availability of triptans will inevitably result in easier access to these medications, which, in turn, may result in improved treatment and lower migraine-related disability. There is currently a lack of empirical evidence that treating migraine effectively does in fact recover lost productivity; well designed studies are required to show this. The availability of triptans OTC is a logical development for the better management of a common, benign, self-limiting but nonetheless burdensome disorder that is currently grossly undertreated. We welcome this development, but recognise that advice at the point of sale is crucial for effective and safe use of these drugs.

Efficacy and safety of 1,000mg effervescent aspirin: individual patient data meta-analysis of three trials in migraine headache and migraine accompanying symptoms

Migraine is often associated with health consequences including impaired quality of life, and the cost of treating migraine headaches places a significant financial burden on patients who suffer from migraines. Nonsteroidal anti-inflammatory drugs (NSAIDs) and triptans are commonly used for the treatment of acute migraine attacks. Aspirin is widely accepted as a treatment option for migraine pain relief and could provide an alternative not only for treatment of moderate migraine attacks, but also for severe migraine attacks. The efficacy and safety of 1,000 mg effervescent aspirin (eASA) was evaluated in comparison to 50 mg sumatriptan and placebo in an individual patient data meta-analysis of three randomized, placebo-controlled, single- dose migraine trials. Pain-relief at 2 h, pain-free at 2 h and sustained pain-free up to 24 h were calculated. For eASA, the response rates were 51.5 % (95 % CI: 46.6-56.5 %), 27.1 % (95 % CI: 22.6-31.4 %), and 23.5 % (95 % CI: 19.3-27.7 %). For sumatriptan, the response rates were 46.6 % (95% CI: 40.0-53.2 %), 29% (95 % CI: 23.0-34.9 %), and 22.2 % (95 % CI: 16.7-27.6 %). The corresponding rates for placebo were 33.9 % (95% CI: 29.1-38.6 %), 15.1 % (95 % CI: 11.5-18.7 %), and 14.6 % (95 % CI: 11.0-18.1 %). The treatment effect of eASA and sumatriptan were significantly different from placebo (p < 0.001), but differences between eASA and sumatriptan were not significant. The remission of accompanying symptoms and the subgroup analyses of patients with moderate or severe migraine pain at baseline revealed no significant differences between eASA and sumatriptan. Safety was evaluated based on the frequency of reported adverse events, and treatment with eASA was associated with lower incidence of adverse events than was with sumatriptan. This individual patient data meta-analysis provided evidence that eASA 1,000 mg is as effective as sumatriptan 50mg for the treatment of acute migraine attacks and has a better side effect profile. This is also true for patients with moderate as well as severe headache at baseline. Patients therefore should be advised to use eASA first for migraine attacks and use a triptan in case of no response.

Pharmacokinetics and interactions of headache medications, part I: introduction, pharmacokinetics, metabolism and acute treatments

Recent progress in the treatment of primary headaches has made available specific, effective and safe medications for these disorders, which are widely spread among the general population. One of the negative consequences of this undoubtedly positive progress is the risk of drug-drug interactions. This review is the first in a two-part series on pharmacokinetic drug-drug interactions of headache medications. Part I addresses acute treatments. Part II focuses on prophylactic treatments. The overall aim of this series is to increase the awareness of physicians, either primary care providers or specialists, regarding this topic. Pharmacokinetic drug-drug interactions of major severity involving acute medications are a minority among those reported in literature. The main drug combinations to avoid are: i) NSAIDs plus drugs with a narrow therapeutic range (i.e., digoxin, methotrexate, etc.); ii) sumatriptan, rizatriptan or zolmitriptan plus monoamine oxidase inhibitors; iii) substrates and inhibitors of CYP2D6 (i.e., chlorpromazine, metoclopramide, etc.) and -3A4 (i.e., ergot derivatives, eletriptan, etc.), as well as other substrates or inhibitors of the same CYP isoenzymes. The risk of having clinically significant pharmacokinetic drug-drug interactions seems to be limited in patients with low frequency headaches, but could be higher in chronic headache sufferers with medication overuse.