Age-related effects of 5-HT2 antagonists

Ketanserin, an S2 antagonist, has been shown to be an effective antihypertensive drug. Carefully controlled clinical trials have demonstrated that ketanserin is as effective as both metoprolol and thiaside diuretics in reducing blood pressure. However, unlike the beta-blocking drug metoprolol and the diuretics, the response rate to ketanserin is significantly greater in older patients, reflecting perhaps the greater vasoconstrictor effects of 5-hydroxytryptamine in patients with atherosclerotic disease. This enhanced vasoconstrictor response to serotonin in elderly patients may be matched by an increased effect on platelet aggregation, which is also blocked by ketanserin. There is very suggestive evidence from the PACK study that ketanserin may reduce vascular thrombotic episodes in patients with extensive atherosclerosis. This unique characteristic, combined with effectiveness as an antihypertensive agent, makes ketanserin a particularly useful drug in the treatment of elderly patients with hypertension and vascular disease.