Signs of early cardiac tamponade induced by Minoxidil.

Minoxidil is an antihypertensive that works by directly dilating peripheral vessels. This medication is typically reserved for patients with resistant hypertension, whose blood pressure remains above goal despite being on multiple agents. A rare but potentially dangerous side effect of Minoxidil is drug-induced pericardial effusion. Here we report a case of a patient who was taking Minoxidil and subsequently developed a large pericardial effusion, with concerns for impending cardiac tamponade.