To : Rachael Re : Clopidrogrel (Plavix) Clopidogrel bisulfate is a platelet aggregation inhibitor. It works slightly diffently than aspirin but they accomplish the same thing. It irreversibly inhibits platelet aggregation so that platelets must be resynthesized to restore activity and this requires a minimum of 5-8 days in adults, probably longer in newborns. It's oral bioavailability is 50%. No data on transfer into human milk is available. I would be somewhat reticent to use this product in the breastfeeding mother of a neonate. Because of the irreversible inhibition of the platelets, even small amounts transferred via milk could suppress platelet function in the newborn. Warfarin, and low molecular weight heparins are probably fine, but I would be really cautious of these platelet antagonists. Regards Tom Hale, Ph.D.