1) Administer cholestyramine 8 gms three times daily for 11 days. (The 11 days do not have to be consecutive unless there is a need to lower the plasma levels rapidly).
2) Verify plasma levels less than 0.02 mg/L (0.02 g/ml) by separate tests at least 14 days apart. If plasma levels are higher than 0.02 mg/L (0.02 g/ml), additional cholestyramine treatment should be considered.
Without the drug elimination procedure, it may take up to two years to reach plasma M1 metabolite levels less than 0.02 mg/L (0.02 g/ml) due to individual variation in drug clearance.
Arava™ should not be used by nursing mothers. It is not known whether Arava™ is excreted in human milk. Many drugs are excreted in human milk, and there is a potential for serious adverse reactions in nursing infants on Arava™. Therefore a decision should be made whether to proceed with nursing or to initiate treatment with Arava™, taking into account the importance of the drug to the mother.
Available information does not suggest that Arava™ would be associated with an increased risk of male-mediated fetal toxicity. However, animal studies to evaluate this specific risk have not been conducted. To minimize any possible risk, men wishing to father a child should consider discontinuing use of Arava™ and taking cholestyramine 8 g , 3 times daily for 11 days.
A. Mechanism of Action (Davis et al 1996, Silva et al 1998, Hermann et al 1997):
Leflunomide is a novel isoxazole immunomodulatory agent, which inhibits de novo pyrimidine synthesis and has antiproliferative activity. Following oral administration, it is rapidly metabolized to an active metabolite (A77 1726), which is presumed to be the active drug