Leflunomide during pregnancy; a case report and review of the literature

Leflunomide is a prodrug for teruflunomide and used for rheumatic diseases. Teriflunomide is considered to be teratogenic and should be avoided in pregnancy. We describe a case of teriflunomide exposure up to the third trimester of pregnancy. A healthy baby was delivered, despite substantial drug exposure. Multiple washout procedures were required to reduce teriflunomide concentrations below the safe target concentration 0.02 mg/L.