Phenothiazines, the group to which

promethazine belongs, exert their influences through blockage of D2 receptors in the basal ganglia and limbic system.[38] The mechanism by which phenothiazines act in migraine is still indefinite. It is probably associated with the cumulative effect of its antagonistic activity at several receptors (adrenergic, muscarinic cholinergic, Pritelivir order histaminic, and serotonergic receptors), as well as at chemoreceptor trigger zone of brain medulla.[39, 40] The clinical pharmacology and practical applications of promethazine hydrochloride have been described by Bain et al.[41] Since its introduction, promethazine has been used as an antiemetic drug for prevention and treatment of nausea and vomiting induced

by narcotic therapy,[42] migraine episodes,[43] cancer chemotherapy,[44] motion sickness,[45] and during labor.[46] The clinical effects appear within average 20 minutes after oral administration with duration of 4-6 hours lasting effect.[47] Promethazine is one of the most important element of antihistaminic drugs providing substantial level of sedation and headache relief.[48] It possesses more sedative effect than some of the other conventional antiemetic medications.[49] In the current trial, according to outpatient basis, the rate of patient selleck compound population reporting a baseline moderate intensity of migraine (65.7% of moderate and 34.3% of severe migraine) corresponds with that frequently included in triptan studies (65% of moderate and 35% of severe migraine).[33, 50] Outpatient selleck kinase inhibitor management is the preferred method for treating acute migraine headache, and consists of nonsteroidal anti-inflammatory drugs, D2 antagonists, serotonin agonists, opioids, local anesthetics, and steroids.[51] In this

study, we decided to study combination of sumatriptan from triptan group and promethazine because sumatriptan as a specific and selective serotonin agonist has extensive efficacy, tolerability, and safety record in acute migraine therapy. The optimum oral dose of sumatriptan has been determined at 50 mg,[52] which is the lowest dose with maximum therapeutic benefit and the highest effective dose with placebo-level AEs.[53] This dosage provides efficacy similar to the 100-mg dose of sumatriptan.[14] Previous studies have demonstrated that oral sumatriptan (50 mg) is an efficient therapy for the variety of headaches reported by the general population of migraine sufferers.[54] Moreover, a meta-analysis of 53 randomized controlled trials of oral triptans showed that the efficacy of sumatriptan 50 mg was widely expressive of the triptan class.[1] Consequently, sumatriptan 50 mg was selected as the active comparator for this trial. Considering the total percentage of patients taking the second dose of study drug, a statistically significant difference was obtained in favor of SP treatment compared with SPr (49.0% vs 22.6%).