Effects of paroxetine hydrochloride, a selective serotonin reuptake inhibitor, on refractory vasovagal syncope: a randomized, double-blind, placebo-controlled study

OBJECTIVES: The purpose of the study was to determine whether the well tolerated serotonin reuptake inhibitor paroxetine hydrochloride could prevent vasovagal syncope in patients resistant to or intolerant of previous traditional therapies. BACKGROUND: Serotonergic mechanisms play a major role in the processes leading to neurocardiogenic vasovagal syncope, and serotonin reuptake inhibitors have been reported to be effective in preventing refractory syncope. METHODS: Sixty-eight consecutive patients (26 men and 42 women, mean age 44.7+/-16.5 years) with recurrent syncope and positive head-up tilt test and in whom standard therapies with beta-adrenergic blocking agents, vagolytic, negative inotropic or mineral corticoid agents were ineffectual or poorly tolerated were referred for study. Patients randomly received either paroxetine at 20 mg once a day or a placebo. A head-up tilt test was then reperformed after one month of treatment, and the clinical effect was noted over a mean follow-up of 25.4+/-7.9 months. RESULTS: The response rates (negative tilt test) after one month of treatment were 61.8% versus 38.2% (p < 0.001) in the paroxetine and placebo groups, respectively. During follow-up spontaneous syncope was reported in six patients (17.6%) in the paroxetine group as compared to 18 patients (52.9%) in the placebo group (p < 0.0001). Only one patient (2.9%) asked to be discontinued from the drug for severe side effects. CONCLUSIONS: Paroxetine was found to significantly improve the symptoms of patients with vasovagal syncope unresponsive to or intolerant of traditional medications and was well tolerated by patients.