Betamethasone-induced hypokalemic periodic paralysis in pregnancy.

Abstract

Acute hypokalemic periodic paralysis may be induced by betamethasone injections during pregnancy. A healthy 23-year-old gravid woman at 32 weeks of gestation with preterm premature rupture of membranes received two doses of 12-mg intramuscular betamethasone 24 hours apart to accelerate fetal lung maturation. She developed significant proximal muscle weakness within 16 hours after the initial dose. Her serum potassium was 1.6 mEq/L. Oral and parenteral potassium replacement restored her neuromuscular function over several days. She delivered by repeat cesarean at 34 weeks of gestation without complications for her or the neonate. Hypokalemic periodic paralysis, a rare cause of weakness, may be induced by betamethasone injections during pregnancy and is reversible with low-risk interventions.