Successful treatment of leflunomide-induced acute pneumonitis with cholestyramine wash-out therapy.

Drug-induced acute pneumonitis is a rare but potentially fatal adverse drug reaction. A high index of suspicion is needed for early diagnosis as it mimics community acquired pneumonia and interstitial lung disease that can occur in rheumatoid arthritis. We report a 32-year-old Chinese lady who suffered from leflunomide-induced pneumonitis and improved dramatically after receiving cholestyramine wash-out therapy. This case illustrates the need for clinical alertness to this potentially fatal complication. When in doubt, discontinuation of leflunomide and empirical wash-out therapy should be administered without delay.