Coadministration has not been studied but based on metabolism and clearance a clinically significant interaction is unlikely. Creatine monohydrate is not degraded during normal digestion and nearly 99% of orally ingested creatine monohydrate is either taken up by muscle or excreted in urine. Raltegravir is mainly metabolized by UGT1A1. Creatine is unlikely to affect UGT1A1.