Thioguanine undergoes complex metabolism primarily in the liver, where it is converted into active metabolites by several enzymatic pathways. Key enzymes involved include thiopurine S-methyltransferase (TPMT) and hypoxanthine-guanine phosphoribosyltransferase (HGPRT). Genetic polymorphisms in TPMT can significantly affect drug metabolism and toxicity, with some individuals being slow metabolizers, increasing the risk of adverse effects.
