Five medications in the triptan class are approved and available for the treatment of migraine headache. These are sumatriptan, zolmitriptan, rizatriptan, almotriptan, and naratriptan. They have similar efficacies. More than one half of patients receiving the injectable form of sumatriptan report pain relief within 30 minutes. Jamieson reviewed the safety of triptans, especially in patients with concomitant vascular disease.
There are approximately 3.4 migraine-related strokes for every 100,000 persons annually, if all patients with migraines and stroke risk factors are included. The number drops to 1.4 if patients who do not have other stroke risk factors are excluded. Thus, a history of migraine is associated with a higher risk of stroke. Triptans work by vasoconstricting the meningeal blood vessels. It has been postulated that the higher rate of vascular events in these patients may be caused by use of these anti-migraine agents. However, the relationship may not be a causal one.
Although triptans cause vasoconstriction, they are more active at cranial vasculature than in other vascular beds. Sometimes patients report chest pain after taking trip-tans, but this complaint is rarely accompanied by electrocardiographic changes. Trip-tans can probably be safely continued, if needed, unless there is other evidence that the chest pain is ischemic. Triptans should be discontinued if the pain seems to be ischemic. Because of their mechanism of action, trip-tans should not be used in patients with uncontrolled hypertension; however, triptans may be an appropriate treatment for migraine if blood pressure is well controlled.
Pregnant women are proscribed from clinical trials of triptans and should not use trip-tans until more data become available. Studies of patients younger than 18 years show that triptans appear to be safe and effective, although they are not labeled by the U.S. Food and Drug Administration for use in children.
Numerous studies have shown that triptans are safe, even with frequent, long-term use. Drug interactions do not seem to be a problem clinically, although numerous suggestions have been made about which drug combinations to avoid, based on knowledge of the pharmacody-namics of triptans. Because they stimulate serotonin receptors, triptans should not be used with other medications that also stimulate these receptors, such as ergotamines. Although serotonin syndrome is rare, it could occur with combined use of a triptan and a selective serotonin reuptake inhibitor. Careful consideration should precede using these agents together.
Monoamine oxidase (MAO) inhibitors can increase the level of triptans in the blood and should not be used with them. Similarly, propranolol, which affects the MAO-A system, has been shown to increase the concentration of rizatriptan. The dosage of rizatriptan should be decreased if it is used with propranolol. See the accompanying table for other limitations to the use of triptans.