Atrial fibrillation associated with sumatriptan.

A 34 year old man with a history of migraine presented with palpitations after taking sumatriptan by nasal spray for a severe headache. Examination was unremarkable apart from atrial fibrillation, with a ventricular rate of 130 beats/min. He recalled having had a fast irregular pulse after taking sumatriptan previously, and this was confirmed from his case notes. He reverted to sinus rhythm spontaneously within 12 hours of admission. Thyroid function tests and a transthoracic echocardiogram gave normal results. Exercise stress testing showed no abnormalities.

Sumatriptan is a 5-hydroxytryptanine agonist active at 5-hyroxytryptanine 1B and 1D receptors. Chest tightness …