TPMT (thiopurine S-methyltransferase)

TPMT (thiopurine S-methyltransferase) is an enzyme in the body responsible for breaking down certain medications, like thiopurines used in treating leukemia and autoimmune diseases. People have different levels of TPMT activity due to genetic differences, which can affect how they process these medicines. Those with low TPMT activity risk drug buildup, leading to side effects, while those with high activity may need higher doses for effectiveness. Testing for TPMT activity helps doctors tailor treatments to improve safety and efficacy, reducing the chance of adverse reactions.