Comparison of Hepatic Transporter Tissue Expression in Rodents and Interspecies Hepatic OCT1 Activity.

Hepatic clearance may be uptake rate limited by organic anion transporting polypeptides (OATPs) and organic cation transporter 1 (OCT1). While comparison of OATP activity has been investigated across species, little has been reported for OCT1. Additionally, while data on interspecies transporter expression in the liver exist, quantitative comparison of these transporters in multiple tissues is lacking. In the current research, the pharmacokinetics of OCT1 substrates (sumatriptan and metformin) were assessed in Oct knockout rats for comparison with previous Oct1/2-/- mice data and OCT1 pharmacogenetics in humans. Effect of OCT1 inhibitors verapamil and erlotinib on OCT1 substrate liver partitioning was also evaluated in rats. Expression of 18 transporters, including Oatps and Octs, in 9 tissues from mice and rats was quantitated using nanoLC/MS-MS, along with uptake transporters in hepatocytes from 5 species. Interspecies differences in OCT1 activity were further evaluated via uptake of OCT1 substrates in hepatocytes with corresponding in vivo liver partitioning in rodents and monkey. In Oct1-/- rats, sumatriptan hepatic clearance and liver partitioning decreased; however, metformin pharmacokinetics were unaffected. OCT1 inhibitor coadministration decreased sumatriptan liver partitioning. In rodents, Oatp expression was highest in the liver, although comparable expression of Oatps in other tissues was determined. Expression of Octs was highest in the kidney, with liver Oct1 expression comparably lower than Oatps. Liver partitioning of OCT1 substrates was lower in rodents than in monkey, in agreement with the highest OCT1 expression and uptake of OCT1 substrates in monkey hepatocytes. Species-dependent OCT1 activity requires consideration when translating preclinical data to the clinic.

Investigation of sumatriptan and ketorolac trometamol in the human experimental model of headache.

BACKGROUND: Pituitary adenylate cyclase-activating polypeptide-38 (PACAP38) induces headache in healthy volunteers but the precise mechanisms by which PACAP38 leads to headache are unclear. We investigated the headache preventive effect of sumatriptan and ketorolac on PACAP38-induced headache in healthy volunteers. In addition, we explored contribution of vascular mechanisms to PACAP38-induced headache using high resolution magnetic resonance angiography. METHODS: Thirty-four healthy volunteers were divided in two groups (A and B) and received infusion of PACAP38 (10 picomol/kg/min) over 20 min. Group A was pretreated with intravenous sumatriptan (4 mg) or ketorolac (30 mg) 20 min before infusion of PACAP38. Group B received infusion of sumatriptan or ketorolac as post-treatment 90 min after infusion of PACAP38. In both experiments, we used a randomized, double-blind, cross-over design. We recorded headache characteristics and circumference of extra-intracerebral arteries. RESULTS: We found no difference in AUC (0-6 h) of PACAP38-induced headache in group A, pretreated with sumatriptan or ketorolac (p = 0.297). There was no difference between sumatriptan and ketorolac in PACAP38-induced circumference change (AUCBaseline-110 min) of MMA (p = 0.227), STA (p = 0.795) and MCA (p = 0.356). In group B, post-treatment with ketorolac reduced PACAP38-headache compared to sumatriptan (p < 0.001). Post-treatment with sumatriptan significantly reduced the circumference of STA (p = 0.039) and MMA (p = 0.015) but not of MCA (p = 0.981) compared to ketorolac. In an explorative analysis, we found that pre-treatment with sumatriptan reduced PACAP38-induced headache compared to no treatment (AUC0-90min). CONCLUSIONS: Post-treatment with ketorolac was more effective in attenuating PACAP38-induced headache compared to sumatriptan. Ketorolac exerted its effect without affecting PACAP38-induced arterial dilation, whereas sumatriptan post-treatment attenuated PACAP38-induced dilation of MMA and STA. Pre-treatment with sumatriptan attenuated PACAP38-induced headache without affecting PACAP38-induced arterial dilation. Our findings suggest that ketorolac and sumatriptan attenuated PACAP38-induced headache in healthy volunteers without vascular effects. TRIAL REGISTRATION: Clinicaltrials.gov (NCT03585894). Registered 13 July 2018.

Experimental and mathematical study of the transdermal delivery of sumatriptan succinate from polyvinylpyrrolidone-based microneedles.

A mechanistic model was developed and tested to predict the release of sumatriptan succinate from dissolving microneedles and its permeation across the epidermal skin layers. Material balance equations were written to describe molecular transport followed by absorption into the systemic circulation. The solid drug particles were encapsulated in pyramid-shaped, polyvinylpyrrolidone-based water-soluble microneedles. Plots, generated from literature values and designed to simulate concentration distributions in the epidermal layers, agreed with optical coherence tomography (OCT)images captured at early stages of the experiments. Simulations showed that an increase in the pitch width led to a faster release of the medication. By modifying the governing equations to include a microneedle baseplate, the model was able to estimate short- and long-term release behaviors from in vitro Franz cellexperiments. These studies were performed using three distinct dissolving microneedle formulations and minipig skin as the biological membrane. The calculated diffusion coefficients were one order of magnitude greater than the value estimated when the drug was directly applied to the skin surface. The dissolution rate constant was affected by the concentration of the polymer matrix.

Transdermal Delivery of Sumatriptan Succinate Using Iontophoresis and Dissolving Microneedles.

This study focuses on the in vitro transdermal transport of sumatriptan succinate using combined iontophoresis and dissolving polymeric microneedle arrays. Permeation experiments were performed to evaluate the effects of formulation parameters on drug release from polyvinylpyrrolidone systems under mild electrical current (≤500 µA/cm2). The preparations consisted of hydrophilic, positively charged molecules encapsulated in a water-soluble and biocompatible polymeric material. Current densities of 100, 300, and 500 µA/cm2 were applied during a 6-h period using silver/silver chloride electrodes. The circular array consisted of 600 needles and occupied a 0.785 cm2 area. Tests, carried out with Franz diffusion cells and skin of Göttingen minipigs, showed that small decreases in the polymer concentration led to negligible lag times and marked increases in the cumulative amount of drug permeated in 6 h (Q6h) and in the flux (Jss). At 500 µA/cm2, Q6h and Jss nearly doubled for a microneedle loaded with 5% (w/w) sumatriptan and 20% (w/w) PVP (lag time = 0 min; Q6h = 2888 µg/cm2; Jss = 490 µg/cm2/h) relative to a system loaded with 5% (w/w) drug and 30% (w/w) PVP (lag time = 36 min; Q6h = 1437 µg/cm2; Jss = 266 µg/cm2/h).

Protective effects of sumatriptan on ischaemia/reperfusion injury following torsion/detorsion in ipsilateral and contralateral testes of rat.

This study was planned to evaluate the effects of sumatriptan, 5-HT1B/1D receptors agonist, on ischaemia/reperfusion injury in bilateral testes after unilateral testicular torsion/detorsion in rats. Male Wistar rats (n = 42) were allocated into a sham-operated group, a control group and treatment groups which were injected sumatriptan (0.1, 0.3 and 1 mg/kg), GR-127935 (0.01 mg/kg)-5-HT1B/1D receptors antagonist-and sumatriptan (0.1 mg/kg) + GR-127935 (0.01 mg/kg). Torsion was induced for 1 hr by rotating right testis 7200 in the clockwise direction, and after 7 days of detorsion, bilateral orchiectomy was conducted. While the level of TNF-α rose in testicular tissue after inducing torsion/detorsion, sumatriptan injection notably lowered TNF-α level in ipsilateral (torted) and contralateral (nontorted) testes (p < 0.001). Moreover, after inducing testicular torsion/detorsion, SOD activity was decreased, whereas administration of sumatriptan significantly increased SOD activity in bilateral testes (p < 0.001). After induction of torsion/detorsion, macroscopic and histological analyses also showed severe damages which were improved by sumatriptan injection. Interestingly, co-administration of sumatriptan with GR-127935 reversed the beneficial impacts of sumatriptan on macroscopic appearance, microscopic pattern and biochemical markers. It is concluded that sumatriptan presumably via stimulation of 5-HT1B/1D receptors decreased inflammation, oxidative stress and deteriorations induced by ischaemia/reperfusion injury following testicular torsion/detorsion.

Survey Analysis of the Use, Effectiveness, and Patient-Reported Tolerability of Inhaled Oxygen Compared With Injectable Sumatriptan for the Acute Treatment of Cluster Headache.

OBJECTIVE: In this secondary analysis of the Clusterbusters® Medication Use survey, the use, effectiveness, and tolerability of inhaled oxygen were investigated and compared with injectable sumatriptan. We also sought to understand the predictors of medication response. BACKGROUND: Inhaled oxygen is a mainstay abortive intervention in cluster headache but is not approved by the Food and Drug Administration (FDA). Unlike injectable sumatriptan, the only FDA-approved pharmacologic intervention for cluster headache, oxygen can be used multiple times a day, which is highly relevant for a condition with numerous daily attacks. In addition to obstacles in obtaining oxygen therapy, optimal oxygen delivery (ie, mask, flow rate) is not uniformly employed in cluster headache. These factors lead to underuse and imprecise therapeutic response rates. METHODS: A secondary analysis was conducted using deidentified data from the Clusterbusters® Medication Use survey, which was modeled after previously published surveys and available online. Subjects were recruited from headache clinics and cluster headache websites. Most responses were chosen from a list; others were free-texted. The final analysis included responses from 493 adult participants with a validated diagnosis of cluster headache. This analysis of deidentified data from the Clusterbusters® Medication Use survey received institutional approval. RESULTS: The most commonly used delivery system used by subjects was a non-rebreather-type mask. The use of oxygen flow rates >10 L/min was a positive predictor of medication response (OR = 2.36, P = .016). Among those who used flow rates >10 L/min, both inhaled oxygen (81.5%) and injectable sumatriptan (80.5%) were efficacious and did not differ significantly from each other in any specific group examined. At flow rates >10 L/min, positive predictors of oxygen response were male gender (OR = 2.07, P = .031) and cigarette smoking (current or historical; OR = 2.25, P = .017). Among the groups examined, there were no predictors of sumatriptan response. Most comments about side effects and concerns were directed at triptans. CONCLUSION: Therapeutic response to inhaled oxygen at sufficiently high flow rates (>10 L/min) had comparable efficacy to that of injectable sumatriptan for the acute treatment of cluster headache. Other factors in oxygen delivery (ie, flow rate changes) should be explored for optimization of therapy. The reasons for improved oxygen response in males and those with a cigarette smoking history require further exploration. While both oxygen and sumatriptan can be effective in the management of cluster headache, patient-reported side effects and concerns were more commonly directed at triptan medications. Current restrictions on access to inhaled oxygen, which exist at many levels, limit the therapeutic options available for patients with cluster headache, thereby doing a disservice to this patient population and the providers who deliver their care.

Modelling the in-vitro dissolution and release of sumatriptan succinate from polyvinylpyrrolidone-based microneedles.

A mathematical model was developed to predict the transport of sumatriptan molecules across the skin followed by absorption into the bloodstream. The drug was encapsulated in dissolving polyvinylpyrrolidone-based microneedles shaped in the form of pyramids. Mass balance equations were derived to simulate the dissolution and transport of the pharmaceutical ingredient. The theoretical framework made it possible to assess and predict the effects of key parameters on the release profile. The skin concentration increased with the loading dose and the height of the microneedle. An inverse relationship was noted between the amount of drug released in the dermal layer and the pitch width. These results were validated with in-vitro diffusion studies previously conducted using Göttingen minipig skin. The new mathematical approach successfully explained the in-vitro permeation of three different sumatriptan-containing formulations.

Induction of chronic migraine phenotypes in a rat model after environmental irritant exposure.

Air pollution is linked to increased emergency department visits for headache and migraine patients frequently cite chemicals or odors as headache triggers, but the association between air pollutants and headache is not well understood. We previously reported that chronic environmental irritant exposure sensitizes the trigeminovascular system response to nasal administration of environmental irritants. Here, we examine whether chronic environmental irritant exposure induces migraine behavioral phenotypes. Male rats were exposed to acrolein, a transient receptor potential channel ankyrin-1 (TRPA1) agonist, or room air by inhalation for 4 days before meningeal blood flow measurements, periorbital cutaneous sensory testing, or other behavioral testing. Touch-induced c-Fos expression in trigeminal nucleus caudalis was compared in animals exposed to room air or acrolein. Spontaneous behavior and olfactory discrimination was examined in open-field testing. Acrolein inhalation exposure produced long-lasting potentiation of blood flow responses to a subsequent TRPA1 agonist and sensitized cutaneous responses to mechanical stimulation. C-Fos expression in response to touch was increased in trigeminal nucleus caudalis in animals exposed to acrolein compared with room air. Spontaneous activity in an open-field and scent preference behavior was different in acrolein-exposed compared with room air-exposed animals. Sumatriptan, an acute migraine treatment blocked acute blood flow changes in response to TRPA1 or transient receptor potential vanilloid receptor-1 agonists. Pretreatment with valproic acid, a prophylactic migraine treatment, attenuated the enhanced blood flow responses observed after acrolein inhalation exposures. Environmental irritant exposure yields an animal model of chronic migraine in which to study mechanisms for enhanced headache susceptibility after chemical exposure.

Soluble guanylyl cyclase is a critical regulator of migraine-associated pain.

Background Nitric oxide (NO) has been heavily implicated in migraine. Nitroglycerin is a prototypic NO-donor, and triggers migraine in humans. However, nitroglycerin also induces oxidative/nitrosative stress and is a source of peroxynitrite - factors previously linked with migraine etiology. Soluble guanylyl cyclase (sGC) is the high affinity NO receptor in the body, and the aim of this study was to identify the precise role of sGC in acute and chronic migraine. Methods We developed a novel brain-bioavailable sGC stimulator (VL-102), and tested its hyperalgesic properties in mice. We also determined the effect of VL-102 on c-fos and calcitonin gene related peptide (CGRP) immunoreactivity within the trigeminovascular complex. In addition, we also tested the known sGC inhibitor, ODQ, within the chronic nitroglycerin migraine model. Results VL-102-evoked acute and chronic mechanical cephalic and hind-paw allodynia in a dose-dependent manner, which was blocked by the migraine medications sumatriptan, propranolol, and topiramate. In addition, VL-102 also increased c-fos and CGRP expressing cells within the trigeminovascular complex. Importantly, ODQ completely inhibited acute and chronic hyperalgesia induced by nitroglycerin. ODQ also blocked hyperalgesia already established by chronic nitroglycerin, implicating this pathway in migraine chronicity. Conclusions These results indicate that nitroglycerin causes migraine-related pain through stimulation of the sGC pathway, and that super-activation of this receptor may be an important component for the maintenance of chronic migraine. This work opens the possibility for negative sGC modulators as novel migraine therapies.

Dissolving polyvinylpyrrolidone-based microneedle systems for in-vitro delivery of sumatriptan succinate.

In-vitro permeation studies were conducted to assess the feasibility of fabricating dissolving-microneedle-array systems to release sumatriptan succinate. The formulations consisted mainly of the encapsulated active ingredient and a water-soluble biologically compatible polymer, polyvinylpyrrolidone (PVP), approved by the U.S. Food and Drug Administration (FDA). Tests with Franz-type diffusion cells and Göttingen minipig skins showed an increase of the transdermal flux compared to passive diffusion. A preparation, containing 30% by mass of PVP and 8.7mg sumatriptan, produced a delivery rate of 395±31µg/cm2h over a 7-hour period after a negligible lag time of approximately 39min. Theoretically, a 10.7cm2 microneedle-array patch loaded with 118.8mg of the drug would provide the required plasma concentration, 72ng/mL, for nearly 7h.

Depression of home cage wheel running: a reliable and clinically relevant method to assess migraine pain in rats.

BACKGROUND: The development of new anti-migraine treatments is limited by the difficulty inassessing migraine pain in laboratory animals. Depression of activity is one of the few diagnostic criteria formigraine that can be mimicked in rats. The goal of the present study was to test the hypothesis thatdepression of home cage wheel running is a reliable and clinically relevant method to assess migraine painin rats. METHODS: Adult female rats were implanted with a cannula to inject allyl isothiocyanate (AITC) onto the dura to induce migraine pain, as has been shown before. Rats recovered from implantation surgery for 8 days in cages containing a running wheel. Home cage wheel running was recorded 23 h a day. AITC and the migraine medication sumatriptan were administered in the hour prior to onset of the dark phase. RESULTS: Administration of AITC caused a concentration-dependent decrease in wheel running that lasted 3 h. The duration and magnitude of AITC-induced depression of wheel running was consistent following three repeated injections spaced 48 h apart. Administration of sumatriptan attenuated AITC-induced depressionof wheel running when a large dose (1 mg/kg) was administered immediately following AITC administration. Wheel running patterns did not change when sumatriptan was given to naïve rats. CONCLUSIONS: These data indicate that home cage wheel running is a sensitive, reliable, and clinically relevant method to assess migraine pain in the rat.

Non-Ablative Fractional Laser to Facilitate Transdermal Delivery.

The advances in laser technology have led to its rapidly expanding applications in dermatology. This study aims at the novel use of a non-ablative fractional laser to enhance transdermal permeation of diclofenac sodium and sumatriptan succinate. The effects of the laser on skin were characterized visually with dye binding, scanning electron microscopy, pore permeability index, and histology. In vitro transdermal permeation of drugs through laser treated and untreated human dermatomed skin was analyzed over 24 h and quantified by HPLC. Drug transport through untreated skin resulted in transdermal delivery of 72.61 µg/cm2 ± 50.35 and 22.80 ± 0.64 µg/cm2 of diclofenac sodium and sumatriptan succinate, respectively. Laser treatment of skin significantly increased (p < 0.005) delivery of diclofenac sodium to 575.66 ± 207.18 µg/cm2 and sumatriptan succinate to 498.32 ± 97.54 µg/cm2. This is a first of its kind study that demonstrates the use of 1410 nm non-ablative fractional laser to enhance transdermal permeation of 2 small molecular weight drugs.

Triptans attenuate circadian responses to light.

Daily exposure to light synchronizes the circadian clock, located in the suprachiasmatic nucleus (SCN), to external day/night cycles. These responses to light can be modified by serotonergic drugs, such as serotonin 5HT1B receptor agonists. Triptans are specific 5HT1B agonists prescribed to treat migraines. Here, we examined the effects of two triptans (zolmitriptan and sumatriptan) on photic phase resetting in Syrian hamsters. Pre-treatment with intra-SCN sumatriptan significantly attenuates, and at higher doses completely blocks, phase advances to light during the late night. Pre-treatment with systemic zolmitriptan significantly attenuates both light-induced phase advances and phase delays. Neither of these drugs, nor their vehicles, causes phase shifts on their own. Pre-treatment with zolmitriptan also significantly reduces the expression of light-induced c-fos in the SCN. Neither zolmitriptan nor vehicle alone induces significant c-fos expression in the SCN. Finally, pre-treatment with zolmitriptan does not attenuate phase shifts to intra-SCN N-methyl-d-aspartate injections, indicating that the mechanism of action for zolmitriptan is likely to be through activation of presynaptic 5HT1B receptors on retinal terminals, thereby decreasing light-induced neurotransmitter release. As triptans are commercially available medications, there is potential for their use in blocking unwanted photic phase shifting during shift-work or jet-lag. Additionally, triptans may also affect the circadian clock in patients receiving them regularly for migraines. Finally, our results may hint at the mechanism by which triptans can alleviate the photophobia that frequently accompanies migraines, namely by activating 5HT1B receptors on retinal terminals elsewhere in the brain, and thereby diminishing visually-evoked neurotransmitter signalling in those areas.

Effects of sumatriptan nasal spray (Imigran) on isolated rat's tracheal smooth muscle.

Sumatriptan (Imigran) is a potent and highly selective 5-HT1 receptor agonist often used in treating acute migraine. Intranasal sumatriptan is well absorbed and is generally effective in relieving headache. However, the effects of Imigran given intratracheally have rarely been well explored. We aimed to verify the effect of Imigran, which acts on the tracheal smooth muscle directly in vitro. We examined the effectiveness of Imigran on isolated rat tracheal smooth muscle by testing: (1) effect on tracheal smooth muscle resting tension; (2) effect on contraction caused by 10(-6) M methacholine as a parasympathetic mimetic; (3) effect of the drugs on electrically induced tracheal smooth muscle contractions. The results indicated that the addition of methacholine to the incubation medium caused the trachea to contract in a dose-dependent manner. The addition of Imigran at doses of 10(-5) M or above elicited a significant relaxation response to 10(-6) M methacholine-induced contraction. Imigran could inhibit electrical field stimulation-induced spike contraction. It also had a minimal effect on the basal tension of trachea as the concentration increased. The study indicated high concentrations of Imigran could cause bronchodilation to reduce asthma attacks not only by blocking parasympathetic tone, but also by directly antagonizing the effect of cholinergic receptors.

Pluronics f-127/l-81 binary hydrogels as drug-delivery systems: influence of physicochemical aspects on release kinetics and cytotoxicity.

We investigated the structure of the binary mixture of Pluronic F-127 (PL F-127) and Pluronic L-81 (PL L-81), as hydrogels for sumatriptan delivery and investigated the mixture possible use via subcutaneous route for future applications as a long-acting antimigraine formulation. We studied the drug-micelle interaction by dynamic light scattering and differential scanning calorimetry, sol-gel process by rheology, and small-angle X-ray scattering (SAXS). We also employed pharmaceutical formulation aspects by dissolution rate, release profile, and cytotoxicity studies for apoptosis and/or necrosis in fibroblasts (3T3) and neural cells (Neuro 2a). Micellar hydrodynamic diameter studies revealed the formation of binary PL-micelles by association of PL F-127/PL L-81. The mixed micelle and binary hydrogels formation was also verified by only one phase transition temperature for all formulations, even in the presence of sumatriptan. The characterization of the hydrogel supramolecular organization by SAXS, rheology studies, and in vitro dissolution/release results showed a probable relationship between the transition of the lamellar to the hexagonal phase and the lower release constant values observed, indicating that PL L-81 participates in micelle-hydrogel formation and aggregation processes. Furthermore, the reduced cytotoxicity (annexin V-fluorescein isothiocyanate positive staining), with minor PL L-81 concentration, points to its potential use for the development of binary PL-systems containing sumatriptan capable of modulating the gelation process. This use may employ the minimum PL concentration and be interesting for pharmaceutical applications, particularly for migraine treatment.

Sumatriptan-associated ischemic colitis: case report and review of the literature and FAERS.

BACKGROUND AND AIMS: Ischemic colitis (IC) is being increasingly recognized, although specific etiological causes are observed in a minority of patients. While several drugs have been associated with IC, most remain anecdotal reports. We recently treated a patient with IC thought to be related to sumatriptan for migraines, and performed a literature review along with a review of the FDA Adverse Event Reporting System (FAERS) database to identify additional cases. METHODS: A MEDLINE/PubMed literature review was conducted using standard IC search terms to identify published cases of sumatriptan and other related "triptan" drug causes of IC. In addition, through a Freedom of Information Act request, we reviewed the adverse gastrointestinal events linked to sumatriptan contained in the FAERS database for the 5-year period 12 March 2008-11 March 2013, in order to determine whether unpublished cases might exist. Our case of IC was analyzed using a causality assessment tool initially developed for use in cases of alosetron (a 5-HT3 receptor antagonist)-related IC. RESULTS: Five published reports (containing a total of seven patients) describing sumatriptan-associated IC in the English language literature were found and reviewed. Another four published reports of related 5-HT1 receptor agonists causing IC (razitriptan n = 1 and naratriptan n = 3) were also analyzed. Among spontaneous reports of possible IC contained in the FAERS database for sumatriptan, there were 19 adverse events coded as "ischemic colitis" and another six coded as "intestinal ischemia" over a 5-year period ending March 2013, but clinical details were lacking. Similarly, five reports of possible IC from FAERS were mentioned in an earlier published report from the late 1990s. All of the published case reports of sumatriptan and related drugs were deemed to have the classic clinical findings and all recovered. There was one instance of possible recurrent IC symptoms in one patient re-exposed to sumatriptan, but not in another. We found that the IC scoring system developed for alosetron was applicable in our sumatriptan case. CONCLUSIONS: Among drug-related causes of IC, sumatriptan joins a growing list of agents with literature reports supported by the finding of suspected cases of IC in the FAERS database. However, the true incidence of IC due to sumatriptan, as well as other causes, cannot be accurately determined because of the likelihood of under-reporting. The structured IC scoring system appears to be applicable for drug-related as well as other etiological causes of IC.

Headache and prolonged dilatation of the middle meningeal artery by PACAP38 in healthy volunteers.

AIM: To explore a possible relationship between vasodilatation and delayed headache we examined the effect of pituitary adenylate cyclase-activating polypeptide-38 (PACAP38) on the middle meningeal artery (MMA) and middle cerebral artery (MCA) using high resolution magnetic resonance angiography (MRA). METHODS: In a double-blind, randomized, placebo-controlled study 14 healthy volunteers were scanned repeatedly after infusion (20 min) of 10 pmol/kg/min PACAP38 or placebo. In addition, four participants were scanned following subcutaneous sumatriptan (6 mg). RESULTS: We found significant dilatation of the MMA (p = 0.00001), but not of the MCA (p = 0.50) after PACAP38. There was no change after placebo (p > 0.40). Vasodilatation (range 16-23%) lasted more than 5 h. Sumatriptan selectively contracted the MMA by 12.3% (p = 0.043). CONCLUSION: PACAP38-induced headache is associated with prolonged dilatation of the MMA but not of the MCA. Sumatriptan relieves headache in parallel with contraction of the MMA but not of the MCA.

Sumatriptan-naproxen and butalbital: a double-blind, placebo-controlled crossover study.

OBJECTIVES: The primary objective was to compare the efficacy of a sumatriptan and naproxen combination medication (SumaRT/Nap-85mg sumatriptan and 500mg naproxen sodium), a butalbital-containing combination medication (BCM-50mg butalbital, 325mg acetaminophen, 40mg caffeine), and placebo when used to treat moderate to severe migraine headache pain in subjects who used BCMs in the past. BACKGROUND: Despite the lack of Food and Drug Administration approval and the absence of placebo-controlled trials to demonstrate efficacy, butalbital-containing medications are among the most commonly prescribed acute migraine treatments in the United States. Butalbital-containing medications are associated with serious and undesirable side effects, and have been linked to the chronification of migraine and development of medication-overuse headaches. This study compares the relative efficacy, safety, and tolerability of a fixed dose SumaRT/Nap versus a BCM and placebo. METHODS: Enrolled subjects were required to have treated at least 1 migraine with a butalbital medication in the past. Enrolled subjects treated 3 moderate to severe migraines using each of the 3 study treatments once in a randomized sequence. The primary endpoint compared SumaRT/Nap versus BCM for sustained pain freedom at 2-24 hours without the use of any rescue medication. This study combines data from 2 identical outpatient, randomized, multicenter, double-blind, double-dummy, 3 attack crossover studies in adult migraineurs (International Classification of Headache Disorders, 2nd edition). RESULTS: A total of 442 subjects treated at least 1 attack with study medication. The majority of the treated subjects were female (88%) with a mean age 43 years, who reported that their migraines had a severe impact on their lives (78% with Headache Impact Test-6 of >59). At screening, 88% of subjects reported current butalbital use; 68% had used butalbital for more than 6 weeks; and 82% reported satisfaction with butalbital. Across treatment groups, 28-29% of subjects took study medication within 15 minutes of migraine onset, 34-37% of subjects took study medication >15 minutes to 2 hours after onset, and 32-36% of subjects took study medication more than 2 hours after onset. This study did not detect a difference at the nominal 0.05 level in percent sustained pain-free between SumaRT/Nap (8%), BCM (6%), and placebo (3%). SumaRT/Nap was superior to BCM for pain free at 2, 4, 6, 8, 24, 48 hours (P≤.044); pain relief (mild or no pain) at 2, 4, 6, 8, 24, 48 hours (P≤.01); sustained pain relief 2-24 hours (P<.001); migraine free (pain free with no nausea, photophobia, or phonophobia) at 4, 6, 8, 24, 48 hours (P≤.046); and complete symptom free (migraine free with no neck/sinus pain) at 4, 6, 8, 48 hours (P≤.031). Adverse event incidence was similar for all treatments (10%, 12%, and 9% for placebo, SumaRT/Nap, and BCM, respectively). Nausea was the most frequent adverse event (2%, 2%, and <1% for placebo, SumaRT/Nap, and BCM, respectively). Five serious adverse events were reported by 3 subjects: viral meningitis and colon neoplasm (placebo); chest pain and hypertension 17 days postdose (SumaRT/Nap); and breast cancer (BCM). Investigators judged no serious adverse events related to study medication. CONCLUSIONS: This study primarily included subjects whose migraines significantly impacted their lives. Before the study, these subjects used butalbital-containing medications as part of their current migraine treatment regimen and were satisfied with it, suggesting they were butalbital responders who had found a workable treatment strategy for themselves. When treated with SumaRT/Nap versus BCM in this study, however, a significant proportion of subjects reported better treatment outcomes for themselves for both migraine pain and associated symptoms. Use of SumaRT/Nap was also associated with less rescue medication use and a longer time before use of rescue medication compared with both BCM and placebo.

Comparação entre o sumatriptano, a trimebutina, o meloxicam e a associação dos três fármacos no tratamento agudo de enxaqueca / Comparison among sumatriptane, trimebutine, meloxicam and the association of those drugs in the acute treatment of migraine

JUSTIFICATIVA E OBJETIVOS: A crise aguda de migrânea geralmente leva a grande incapacidade econômica e social para aqueles que sofrem deste transtorno. A fisiopatologia é complexa e envolve múltiplos mecanismos centrais e periféricos. O tratamento agudo tem como objetivo aliviar a dor e os fenômenos associados como a náusea e fotofobia, sem causar efeitos adversos importantes. Apesar do desenvolvimento de fármacos específicos como os triptanos, para o tratamento agudo, a sua eficácia ainda é baixa. O objetivo deste estudo foi comparar a eficácia e a tolerância da trimebutina, meloxicam, sumatriptano e a associação dos três fármacos no tratamento das crises agudas de migrânea de moderada a forte intensidade.MÉTODO: Após aprovação pelo Comitê de Ética das Instituições foram incluídos neste estudo prospectivo, duplamente encoberto e aleatório, 50 pacientes, sendo 43 mulheres e 7 homens, com idade entre 18 e 65 anos, portadores de migrânea com ou sem aura, que utilizavam medicação profilática, exceto anti-inflamatórios não esteroides (AINES). Foram tratadas quatro crises de migrânea de moderada a forte intensidade de cada paciente, com 200 mg de trimebutina, 50 mg de sumatriptano, 15 mg de meloxicam ou com a associação de 200 mg de trimebutina, 50 mg de sumatriptano e 15 mg de meloxicam. Os pacientes foram aleatorizados em 4 grupos de acordo com a ordem de chegada, de modo que o primeiro paciente incluído recebeu trimebutina para a primeira crise, sumatriptano para a segunda crise, meloxicam para a terceira crise e a associação entre os 3 fármacos para a quarta crise. O segundo paciente incluído recebeu sumatriptano para a primeira crise, meloxicam para a segunda superior a cada um desses fármacos isolados para controlar a dor, as náuseas e a fotofobia nas crises agudas de migrânea de moderada a forte intensidade. Além disso, a combinação dos fármacos apresentou maior incidência de efeitos adversos.crise, a associação para a terceira crise e a trimebutina para a quarta crise, e assim sucessivamente. A intensidade da crise de migrânea foi avaliada a partir da ingestão da cápsula com escala categorizada verbal na qual: 0 - sem dor, 1 - cefaleia leve, 2 - cefaleia moderada e 3 - cefaleia intensa. Cada paciente foi orientado para preencher o relatório de crise para cada crise tratada, na qual anotava a intensidade da cefaleia, a presença de náusea, fotofobia e dos efeitos adversos, e o uso da medicação de resgate, 100 mg de indometacina por via retal. RESULTADOS: Completaram o estudo 42 pacientes. Em uma hora 9,5% dos pacientes que utilizaram a associação dos fármacos estavam livres da dor, comparados com 14,2% com a trimebutina e sumatriptano e 2,4% com o meloxicam (p = 0,479). Em duas horas 21,4% dos pacientes que usaram a associação estavam livres da dor, comparados com 11,9% com a trimebutina, 26,1% com sumatriptano e 23,8% com o meloxicam (p = 0,555). Tanto a associação trimebutina, sumatriptano e meloxicam como os fármacos trimebutina, sumatriptano e meloxicam isolados foram efetivos para controlar a náusea e fotofobia após 1 e 2h para náusea (p = 0,157 e 0,587) e fotofobia (p = 0,671 e 0,929, embora sem diferença estatisticamente significativa entre eles. Dez pacientes em uso da associação dos fármacos, 6 em uso da trimebutina, 5 em uso do sumatriptano e 5 em uso do meloxicam relataram efeitos colaterais. CONCLUSÃO: Este estudo demonstrou que a associação sumatriptano, meloxicam e trimebutina não foi superior a cada um desses fármacos isolados para controlar a dor, as náuseas e a fotofobia nas crises agudas de migrânea de moderada a forte intensidade. Além disso, a combinação dos fármacos apresentou maior incidência de efeitos adversos.

BACKGROUND AND OBJECTIVES: Acute migraine crisis often leads to major economic and social disability for those suffering from such syndrome. Pathophysiology is complex involving several central and peripheral mechanisms. The acute treatment aims at evaluating pain and associated phenomena, such as nausea and photophobia, without causing major adverse effects. Notwithstanding the development of specific drugs for the acute treatment, such as triptanes, their efficacy is still low. This study aimed at comparing efficacy and tolerance of trimebutine, meloxicam, sumatriptane and the association of such drugs to treat moderate to severe acute migraine crises.METHOD: After the Institutions? Ethics Committee approval, participated in this prospective, double-blind and randomized study 50 patients, being 43 females and 7 males, aged between 18 and 65 years, with migraine with or without aura, under prophylactic medication, except non-steroid anti-inflammatory drugs (NSAIDS). Patients were treated for 4 moderate to severe migraine crises with 200 mg trimebutine, 50 mg sumatriptane, 15 mg meloxicam, or with the association of 200 mg trimebutine, 50 mg sumatriptane and 15 mg meloxicam. Patients were randomized in 4 groups according to their arrival, so that the first patient included received trimebutine for the first crisis, sumatriptane for the second crisis, meloxicam for the third crisis and the association of the three drugs for the fourth crisis. The second patient included received sumatriptane for the first crisis, meloxicam for the second crisis, the association for the third crisis and trimebutine for the fourth crisis, and so on and so forth. Migraine crisis intensity was evaluated as from the ingestion of the first tablet with verbal categorized scale where: 0 = no pain, 1 = mild headache, 2 = moderate headache, 3 = severe headache. All patients were oriented to fill a crisis report for each treated crisis, where they would record headache intensity, presence of nausea, photophobia and adverse effects and the use of rescue medication, 100 mg of rectal indometacin.RESULTS: Forty-two patients completed the study. In one hour 9.5% of patients using the association of drugs were free of pain, as compared to 14.2% with trimebutine and sumatriptane and 2.4% with meloxicam (p = 0.479). In two hours 21.4% of patients using the association were free of pain, as compared to 11.9% with trimebutine, 26.1% with sumatriptane and 23.6% with meloxicam (p = 0.555). Both the association of trimebutine, sumatriptane and meloxicam and trimebutine, sumatriptane and meloxicam alone were effective to control nausea and photophobia after 1 and 2 h for nausea (p = 0.157 and 0.587) and photophobia (p = 0.671 and 0.929) although without statistically significant difference among them. Ten patients under the association of drugs, 6 under trimebutine, 5 under sumatriptane and 5 under meloxicam have reported side effects. CONCLUSION: This study has shown that the association of sumatriptane, meloxicam and trimebutine was not better than each of those drugs alone to control pain, nausea and photophobia during moderate to severe migraine crises. In addition, the combination of drugs has shown a higher incidence of adverse effects.

Ischemic colitis related to sumatriptan overuse.

BACKGROUND: Serotonin-1 5-hydroxytryptamine (5-HT 1) receptor agonists are first line agents for migraine headaches. Patients with refractory headaches may use supratherapeutic doses of these medications. Described is a case of ischemic colitis related to overuse of sumatriptan. CASE: A 35-year-old woman presented with severe abdominal pain without diarrhea or hematochezia. For several days prior she had been self-treating a refractory migraine headache with frequent doses of sumatriptan. She is a nonsmoker and took no oral contraceptives or other serotonin agonists. A computed tomography scan of the abdomen revealed left-sided colitis. A colonoscopy with biopsy confirmed ischemic colitis and excluded inflammatory bowel disease (IBD). DISCUSSION: Previously published case reports have suggested an association between 5-HT 1 receptor agonists and ischemic colitis. These reports have been dismissed because the patients were taking oral contraceptives, serotonin agonists, or had other comorbidities. This healthy patient lacked risk factors for ischemia, is the youngest to be reported, and is the first without hematochezia. CONCLUSION: 5-HT 1 receptor agonists are generally considered safe. Ischemic colitis is a potentially serious complication of these agents. A retrospective review of 5-HT 1 receptor agonist users who have presented with acute onset abdominal pain or hematochezia is necessary to elucidate the incidence of this adverse event.