Serotonin antagonism and serotonin antagonists in pregnancy: role of ketanserin.

ABSTRACT

UNLABELLED Most agree that antihypertensive medication should be used to treat severe hypertension during pregnancy, but its role in patients with mild to moderate disease is debated. None of the regularly used drugs is completely safe for mother and fetus. Ketanserin decreases systolic and diastolic blood pressure in nonpregnant patients with acute and chronic hypertension. Its selective serotonin S2-receptor antagonist activity encouraged investigations into a possible role in pregnant women. These reports can be divided into four groups. Several studies confirmed that intravenous ketanserin decreases blood pressure significantly in patients with severe preeclampsia. There are indications that it may be at least as effective as dihydralazine, possibly with fewer side effects. Its role in chronic hypertension has not been studied adequately, but one randomized, controlled trial indicated efficacy comparable with that of alpha-methyldopa. Thirdly, it was concluded in a single descriptive study that the administration of ketanserin to patients with HELLP syndrome allowed delivery to be postponed for 5.3 days. Lastly, in a randomized, placebo-controlled trial, the addition of ketanserin to aspirin in patients with mild to moderate midtrimester hypertension was associated with a significant decrease in the number of cases of preeclampsia and severe hypertension, as well as a trend to less perinatal mortality, lower rates of abruptio placentae, and early-onset preeclampsia. Additional studies are needed to adequately assess a possible role for ketanserin with acute hypertension or moderate chronic hypertension. TARGET AUDIENCE Obstetricians & Gynecologists, Family Physicians LEARNING OBJECTIVES: After completion of this article, the reader will be able to list the various drugs and their associated side effects that are used to treat hypertensive disorders during pregnancy; to describe the various effects of serotonin on the cardiovascular system; to summarize the literature concerning the use of ketanserin during pregnancy; and to list the potential uses of ketanserin in this setting.