Reversible acute fetal renal failure due to maternal exposure to angiotensin receptor blocker.

We report on a case of fetal toxicity due to maternal treatment with olmesartan medoxomil. At 29 weeks' gestation, oligohydramnios was found, although the fetus had normal kidneys on ultrasound evaluation. Withdrawal of olmesartan medoxomil, maternal rehydration, and a single dose of furosemide reversed the renal impairment. After term delivery, the neonate was confirmed to have normal renal function. The case suggested that fetal renal impairment due to olmesartan medoxomil may be reversible.