Serotonin antagonism in panic disorder: an open trial with ritanserin.

Eleven patients with panic disorder were administered ritanserin, a post-synaptic serotonin S2 antagonist, during a 4 week period at a daily dose of 10-20 mg. The treatment resulted in a decrease in the number of panic attacks, and a diminution of agoraphobic avoidance. The possible practical and theoretical signification of these findings is discussed.