Mercaptopurine (6-MP), sold under the brand name Purinethol among others, is a medication used for cancer and autoimmune diseases. Specifically it is used to treat acute lymphocytic leukemia (ALL), acute promyelocytic leukemia (APL), Crohns disease, and ulcerative colitis. For acute lymphocytic leukemia it is generally used with methotrexate. It is taken by mouth.Common side effects include bone marrow suppression, liver toxicity, vomiting, and loss of appetite. Other serious side effects include an increased risk of future cancer and pancreatitis. Those with a genetic deficiency in thiopurine S-methyltransferase are at higher risk of side effects. Use in pregnancy may harm the baby. Mercaptopurine
is in the thiopurine and antimetabolite family of medications.Mercaptopurine was approved for medical use in the United States in 1953. It is on the World Health Organizations List of Essential Medicines. Medical uses
It is used to treat acute lymphocytic leukemia, Crohns disease, and ulcerative colitis. Side effects
Some of the adverse reactions of taking mercaptopurine may include diarrhea, nausea, vomiting, loss of appetite, fatigue, stomach/abdominal pain, weakness, skin rash, darkening of the skin, and hair loss. Serious adverse reactions include mouth sores, fever, sore throat, easy bruising or bleeding, pinpoint red spots on the skin, yellowing of eyes or skin, dark urine, and painful or difficult urination. Other more serious side effects include black or tarry stools (melena), bloody stools, and bloody urine. Treatment is discontinued in up to 30% of patients due these effects but therapeutic drug monitoring of the biologically active  metabolites, i.e.
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