Are there reasons to believe that the antihypertensive effects of serotonin (S2) antagonists are age-related?

The potential age-dependent antihypertensive responses to serotonin antagonists are critically reviewed with regard to the following considerations: Are they beneficial to the patient? Are they related to age-dependent changes in pharmacokinetics or pharmacodynamics? Are they necessarily true? The paper is focused on ketanserin, which is the only major serotonin (S2) antagonist that has yet been used to any extent in patients. Based on the available data in the literature, we conclude that the age-related antihypertensive effect of ketanserin is a beneficial phenomenon since it does not seem to be paralleled by a corresponding increase in side effects. Furthermore, the mechanism seems to be due to changes in the pharmacodynamics of the drug on the platelet or vascular smooth muscle since there is only negligible alteration in pharmacokinetics occurring with advanced age. Although multiple independent trials or pooled data strongly indicate that the efficacy of ketanserin increases with age, not all investigators agree. In our opinion, the interindividual variation in drug response is more characteristic to the drug than the relationship to age. Therefore, the selection of patients for ketanserin therapy should be based on individual testing in addition to age grouping.