ATC code: C07AG01
The antihypertensive effect of labetalol is similar in men and women.
When receiving the same dose, women achieve much higher plasma concentration of labetalol than men. It is mainly the concentration of the inactive stereoisomers that is higher in women, whereas the concentration of the active beta-blocking isomer is similar between the sexes.
A randomized, crossover study (14 men, 5 women) evaluated the impact of patient’s sex on labetalol kinetics. Patients had labetalol dosages titrated from 100 mg twice/day to a specific antihypertensive response. Despite receiving similar average dosages and having similar body weight, significant sex differences were seen in labetalol kinetics. Oral clearance was higher in men. Plasma concentrations were 80% higher in women than men, but the drug’s effect on blood pressure was similar in men and women. The dose-corrected for AUC for the beta-blocking R,R-labetalol was only 10% higher in women, while AUC for the other stereoisomers were 56-77% higher. Thus, the sex differences in labetalol kinetics seem to be due to differences in active alpha-blocking stereoisomers but not in beta-blocking stereoisomers [1].
Labetalol in women with pregnancy-induced hypertension was found to have shorter serum half-life but similar clearance, as compared with those of non-pregnant hypertensive and normotensive populations [2].
A small randomized study (14 men, 5 women) has shown that men and women achieved similar blood pressure reduction from labetalol, even though plasma concentration was much higher in women than men [1].
Labetalol in women with pregnancy-induced hypertension was well tolerated by all patients with no adverse effects reported [2].
Regarding teratogenic aspects, please consult Janusmed Drugs and Birth Defects (in Swedish, Janusmed fosterpåverkan).
Updated: 2020-08-28
Date of litterature search: 2019-05-16
Reviewed by: Mia von Euler
Approved by: Karin Schenck-Gustafsson