Sumatriptan, sold commonly under  brand names Imitrex and Treximet among others, is a medication used to treat migraine headaches and cluster headaches. It is taken orally, intranasally, or by subcutaneous injection. Therapeutic effects generally occur within three hours.Its primary effect as a serotonin 5-HT1B/1D receptor agonist can create common side effects such as chest pressure, fatigue, vomiting, tingling, and vertigo. Serious side effects may include serotonin syndrome, heart attacks, strokes, and seizures. With excessive medication overuse headaches may occur. It is unclear if use during pregnancy or breastfeeding is safe. The mechanism of action not entirely clear. It is in the triptan class of medications.Sumatriptan was patented in 1982 and approved for medical use in 1991. It is on the World Health Organizations List of Essential Medicines. It is available as a generic medication. In 2019, it was the 98th most commonly prescribed medication in the United States, with more than seven million prescriptions. It is also available as the combination product sumatriptan/naproxen. Medical uses
Sumatriptan is effective for ending or relieving the intensity of migraine and cluster headaches. It is most effective when taken early after the start of the pain. Injected sumatriptan is more effective than other formulations.Oral sumatriptan can be used also in the treatment of post-dural puncture headache. Adverse effects
Overdose of sumatriptan can cause sulfhemoglobinemia, a rare condition in which the blood changes from red to green, due to the integration of sulfur into the hemoglobin molecule. If sumatriptan is discontinued, the condition reverses within a few weeks.
CGRP is believed to cause sensitization of trigeminal nociceptive neurons, contributing to the pain experienced in migraine.Sumatriptan is also shown to decrease the activity of the trigeminal nerve, which presumably accounts for sumatriptans efficacy in treating cluster headaches. The injectable form of the drug has been shown to abort a cluster headache within 30 minutes in 77% of cases. Pharmacokinetics
Sumatriptan is administered in several forms: tablets, subcutaneous injection, and nasal spray. Oral administration (as succinate salt) has low bioavailability, partly due to presystemic metabolism—some of it gets broken down in the stomach and bloodstream before it reaches the target arteries. A rapid-release tablet formulation with the same bioavailability but a high concentration can achieve therapeutic effects on average 10–15 minutes earlier than other oral forumulations. When injected, sumatriptan is faster-acting (usually within 10 minutes), but the effect lasts for a shorter time. Sumatriptan is metabolised primarily by monoamine oxidase A into 2-{5-[(methylsulfamoyl)methyl]-indole-3-yl}acetic acid, which is then conjugated to glucuronic acid. These metabolites are excreted in the urine and bile. Only about 3% of the active drug may be recovered unchanged. There is no simple, direct relationship between sumatriptan concentration (pharmacokinetics) per se in the blood and its anti-migraine effect (pharmacodynamics). This paradox has, to some extent, been resolved by comparing the rates of absorption of the various sumatriptan formulations, rather than the absolute amounts of drug that they deliver. History
In 1991, Glaxo received approval for sumatriptan, which was the first available triptan. In July 2009, the US FDA approved a single-use jet injector formulation of sumatriptan.