Almotriptan is the first FDA-approved drug used to treat migraine headaches in adults with or without an aura.[1] The drug is also useful in adolescents with a history of a migraine that, when left untreated, lasts 4 hours or longer. Certain triptan medications such as almotriptan and rizatriptan have also shown to be effective and safe for the management of acute migraines and other benign headaches in the pediatric population (less than 18 years of age).[2] 

Almotriptan has approval for use as monotherapy and in conjunction with migraine-abortive medications such as non-steroidal anti-inflammatory drugs (e.g., aceclofenac).[3] It is usually taken by mouth as a tablet.[4] Almotriptan is a white, coated circular tablet, and requires a prescription from a registered physician in the United States.[5] 

In pregnant women with migraines or headaches, triptan use is less frequent; where drugs like metoclopramide, and acetaminophen are more common choices for migraines due to their effectiveness and safety.[6] Triptans have also found to be quite effective in treating menstrual migraines in premenopausal women. Various studies have shown that among the triptans, rizatriptan has proven to be the most beneficial in treating acute menstrual migraines in females.[7] A randomized, placebo-controlled study showed that rizatriptan provided pain relief between 2 to 24 hours with an efficacy of 63 percent when compared to other classes of triptans.[7] 

Almotriptan is a selective serotonin agonist on the 5-HT1B and 5-HT1D receptors in the cranial arteries. Activation of the 5HT receptors is associated with a reduction in neurogenic inflammation, which researchers hypothesize to be involved in the migraine relief process.

Almotriptan works by narrowing the blood vessels in the brain, thereby reducing the cerebral blood flow, stopping the transmission of pain signals to the brain center.[8] The drug has a relatively short half-life of 3 hours, and research the oral bioavailability was found to be 69.1%.[9] Almotriptan is excreted in the urine and metabolized predominantly by the cytochrome CYP450 system.[9] When compared with earlier generation triptans such as sumatriptan, almotriptan has a higher oral bioavailability and a shorter plasma half-life.[8]

The recommended oral dose of almotriptan is 12.5 mg for the effective treatment of acute migraine attacks in adults and adolescents.[9] The dose may be repeated after two hours if a headache returns. It is recommended not to administer more than two doses or more than 25 mg/day. Studies have also shown that almotriptan has a synergistic effect when combined with aceclofenac 100 mg in the treatment of an acute migraine attack.[3] 

Food intake has not demonstrated any effect on the absorption of almotriptan; therefore, its dosing can be without regard to food intake.[9] Dosing adjustment recommended in patients with renal insufficiency. Dosing adjustment is necessary when the drug used with cytochrome P450 inducers (e.g., phenytoin, phenobarbital) and with cytochrome P450 inhibitors (e.g., antibiotics, grapefruit juice, ketoconazole, protease inhibitors). 

The common adverse effects of almotriptan are drowsiness, dizziness, headache, nausea, vomiting, chest pain, and fatigue.[10] The drug is associated with a similar incidence of nausea/vomiting as compared to other classes of triptans (e.g., sumatriptan). However, it shows a decreased incidence of the other common adverse effects listed above, especially when compared to first-generation triptans.[8][10] 

Almotriptan works on the 5HT1B receptors which are present in the coronary arteries; thus, the administration may result in coronary artery narrowing or spasms, leading to potential coronary artery vasospasm or myocardial infarction.[11] Some rare side effects of almotriptan include pulmonary vasoconstriction, serotonin syndrome, inhibition of trigeminal nerves.[12][13]

Almotriptan is contraindicated in patients with renal dysfunction or insufficiency, as well as in the elderly due to a physiological decrease in renal function and renal clearance with advanced age.[9] 

Minor clearance of almotriptan occurs through the CYPP450 system (specifically, CYP3A4); therefore, the clinician should avoid other drugs metabolized through this pathway because they may decrease almotriptan clearance. These drugs include but are not limited to verapamil, nifedipine, losartan, cyclosporine, and moclobemide.[9] It is then reasonable to assume that patients with a mutation in this specific enzyme should be cautious in dosing the drug.

Contraindications to almotriptan also include patients with underlying cardiovascular disease due to the presence of 5HT1B receptors on the coronary arteries. Almotriptan can potentially attach to such receptors resulting in further narrowing or spasm of the arteries.[11] Patients with hypersensitivity to almotriptan should not use the drug, nor should patients that may have a history of a hemiplegic or basilar migraine or a heart condition. Moreover, this medication is not for use in patients that have cerebrovascular syndromes, peripheral vascular disease, or high blood pressure. Caution is necessary if dosing almotriptan within 24 hours of use of a serotonin agonist or an ergotamine-classified medication due to the vasoconstrictive effects of both drugs.[13]