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PURINETHOL®
(mercaptopurine) 50-mg Scored Tablets
CAUTION
PURINETHOL (mercaptopurine) is a potent drug. It should not be used unless a diagnosis of acute lymphatic leukemia has been adequately established and the responsible physician is experienced with the risks of PURINETHOL and knowledgeable in assessing response to chemotherapy.
PURINETHOL (mercaptopurine) was synthesized and developed by Hitchings, Elion, and associates at the Wellcome Research Laboratories.
Mercaptopurine, known chemically as l,7-dihydro-6H-purine-6-thione monohydrate, is an analogue of the purine bases adenine and hypoxanthine. Its structural formula is:
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PURINETHOL is available in tablet form for oral administration. Each scored tablet contains 50 mg mercaptopurine and the inactive ingredients corn and potato starch, lactose, magnesium stearate, and stearic acid.
Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.
Stop using mercaptopurine and call your doctor at once if you have any of these serious side effects:
Read All Potential Side Effects and See Pictures of Purinethol »
Before taking mercaptopurine, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.
This medication should not be used if you have a certain medical condition. Before taking this medicine, consult your doctor or pharmacist if a certain drug (thioguanine) did not work for you in the past. This may affect how well mercaptopurine works for you.
Before using this medication, tell your doctor or pharmacist your medical history, especially of: other blood disorders (e.g., anemia, low blood cell counts), gout, kidney disease (including kidney stones), liver disease, pancreatitis, radiation treatment,...
Last reviewed on RxList: 7/1/2011
This monograph has been modified to include the generic and brand name in many instances.
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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