Drug points

In their drug point reporting that leflunomide can potentiate the anticoagulant effect of warfarin, V Lim and I Pande stated in the last paragraph that the Committee on Safety of Medicines (CSM) had received over 300 reports of raised international normalised ratio (INR) in patients taking leflunomide concurrently with warfarin (BMJ 2002;325:1333). This is wrong. The CSM has in fact received over 300 reports of raised INR associated with warfarin and some other drug; four of these reports (up to mid-December 2002) were of raised INR associated with leflunomide. The authors say that the message remains the same, however—that care is needed when prescribing leflunomide in patients already taking warfarin.