Heart Beat

Little support for that sinking feeling

Fainting is frightening. Fortunately, it's a one-time thing for most people, brought on by standing too long, dehydration, an injection, or other triggers. Some people, though, faint repeatedly. If the culprit is a slow heartbeat, a pacemaker can halt fainting spells. If it isn't — a condition that doctors call neurocardiogenic syncope (SING-cuh-pee) — several "may help" options are available. A clinical trial casts doubt on one of these: the use of a beta blocker.

In the Prevention of Syncope Trial (POST), more than 200 people with recurrent fainting spells took the beta blocker metoprolol or a placebo. After a year, fainting episodes were equally common in both groups.