Fenfluramine-associated hypertension

Fenfluramine is a recently introduced anorexigenic drug for the treatment of obesity. 5 cases of hypertension induced or aggravated by fenfluramine are described. They include 4 females and one male seen and followed in the Hypertension Clinic of the Lagos University Teaching Hospital. Even though there was loss of weight while they were on fenfluramine there was a rise in blood pressure in 4 of them despite concurrent therapy with antihypertensive agents. In one female patient the rise in blood pressure occurred while on self-medication with the drug alone. In all of them the blood pressure fell when fenfluramine was stopped. Although there have been many reports of the effectiveness in the treatment of obesity, reports of its adverse reactions have been few and there has been no mention of hypertension. The drug brochure warns that hypotension may even occur. In view of the present case reports it is advisable that those who are on fenfluramine should have their blood pressure checked regularly particularly if they are also known to be hypertensive.