Fetal Risk Summary
Nimodipine is a calcium channel-blocking agent used to reduce the incidence and severity of ischemic deficits in patients with subarachnoid hemorrhage after rupture of congenital aneurysms. The drug produced a dose-related increase in the incidence of malformations and stunted fetuses in rabbits (1). In rats, nimodipine was embryotoxic, causing resorptions and stunted fetal growth, but except for skeletal variations, caused no malformations (1).
Two cases have been described in which the drug was used as a cerebral vasodilator for the treatment of eclampsia complicated by cerebral vasospasm and edema, but in both cases delivery of the fetus had occurred a few hours before initiation of treatment (2,3). The investigators recommended that nimodipine not be used in combination with magnesium sulfate because of the risk for maternal heart block (3).
A prospective, multicenter cohort study of 78 women (81 outcomes; 3 sets of twins) who had 1st-trimester exposure to calcium channel blockers, including 11% to nimodipine, was reported in 1996 (4). Compared with controls, no increase in the risk of major congenital malformations was found.
Breast Feeding Summary
Nimodipine and its metabolites are concentrated in the milk of lactating rats (1). No reports describing the use of the drug during human lactation have been located.
- Product information. Nimotop. Bayer, 2000.
- Horn EH, Filshie M, Kerslake RW, Jaspan T, Worthington BS, Rubin PC. Widespread cerebral ischaemia treated with nimodipine in a patient with eclampsia. Br Med J 1990;301:794.
- Belfort MA, Carpenter RJ Jr, Kirshon B, Saade GR, Moise KJ Jr. The use of nimodipine in a patient with eclampsia: color flow Doppler demonstration of retinal artery relaxation. Am J Obstet Gynecol 1993;169:2046.
- Magee LA, Schick B, Donnenfeld AE, Sage SR, Conover B, Cook L, McElhatton PR, Schmidt MA, Koren G. The safety of calcium channel blockers in human pregnancy: a prospective, multicenter cohort study. Am J Obstet Gynecol 1996;174:8238.