Neurally mediated syncope and serotonin reuptake inhibitors.

Serotonin (5-hydroxytryptamine or 5HT) is a neurotransmitter which appears to play a prominent role in central regulation of heart rate and blood pressure. Recent evidence suggests that the activation of cerebral serotonin receptors results in a depressor effect principally through sympatho-inhibition. Several common clinical disorders resulting in hypotension leading to syncope are neurally mediated syncope, carotid sinus hypersensitivity and orthostatic hypotension, each of which may involve a serotonergic component. This brief review provides a summary of serotonergic blood pressure regulation, as well as the initial experience with the clinical effects of the serotonin reuptake inhibitors in the therapy of the aforementioned disorders.