A randomized cross over trial of oral nifedipine and intravenous labetalol in pregnant women with severe pre-eclampsia and eclampsia

Kirtan Krishna, N. Shailaja, B. Shyamasundara Bhat, L. Krishna, Namrata .


Background: The aim of treatment of severe pre-eclampsia and eclampsia is to quickly bring about a smooth reduction in blood pressure to levels that are safe for both mother and baby but avoiding any sudden drops. There are not many studies comparing nifedipine and labetalol for this purpose. Authors conducted this study with the aim of comparing their efficacy in reducing maternal blood pressure.

Methods: It was a cross over trial with 30 patients in each group conducted at a tertiary care hospital. 60 pregnant women were randomized to receive nifedipine (20mg loading dose followed by 10 mg tablet, orally, up to maximum of five doses) or  intravenous labetalol  (in an escalating dose regimen of 20, 40, 80, 80 and 80 mg)  every 20 minutes until the target blood pressure of 150/100 mmHg was achieved. Crossover treatment was affected if the initial treatment regimen was unsuccessful after 20 min of the last dose of the drug in the respective groups.

Results: The mean time to achieve the target blood pressure was 32.0 ±18.64 minutes (mean ± SD) in nifedipine group as compared with 37.04 ± 16.36 minutes in those receiving labetalol (P = .002). In the nifedipine group 63.3% required only one dose compared to 36.6% in the labetalol group.  Only two women in the nifedipine group required maximum number of doses that is five doses. Cross over treatment was required by 10% of patients in the labetalol group and none in the nifedipine group.

Conclusions: This study shows that oral nifedipine is more effective than intravenous labetalol in rapid control of hypertension in severe pre-eclampsia and eclampsia.


Eclampsia, Hypertension, Labetalol, Nifedipine, Pre-eclampsia

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