MedlinePlus Drug Information: Mercaptopurine

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Other drug names:	A-Am An-Az B C-Ch Ci-Cz D-Dh Di-Dz E F G H I-J K-L M-Mh Mi-Mz N-Nh Ni-Nz O P-Pl Pm-Pz Q-R S-Sn So-Sz T-To Tp-Tz U-V W-Z 0-9

Mercaptopurine

(mer kap toe pyoor' een)

Brand name(s): Purinethol
Other name(s): 6-MP

Contents of this page:
About your treatment Other uses for this medicine Precautions	Side effects Special instructions

About your treatment

Your doctor has ordered the drug mercaptopurine to help treat your illness. The drug is taken by mouth in tablet form.

This medication is used to treat:

leukemia

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

Mercaptopurine belongs to a group of drugs known as antimetabolites. It resembles a normal cell nutrient needed by cancer cells to grow. The cancer cells take up mercaptopurine which then interferes with their growth.

Other uses for this medicine

Mercaptopurine also is used to treat many types of autoimmune diseases such as systemic lupus erythematosus, rheumatoid arthritis, acute idiopathic polyneuritis, acute idiopathic nephrotic syndrome, psoriatic arthritis, erythroid aplasia, or myelofibrosis; idiopathic hemolytic anemia; macroglobulinemia; idiopathic thrombocytopenia purpura; idiopathic pulmonary hemosiderosis; multiple sclerosis; myasthenia gravis; uveitis; and ulcerative colitis. Talk to your doctor about the possible risks of using this drug for your condition.

Precautions

Before taking mercaptopurine,

tell your doctor and pharmacist if you are allergic to mercaptopurine or any other drugs.
tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially allopurinol (Zyloprim), anticoagulants ('blood thinners') such as warfarin (Coumadin), aspirin, and vitamins.
you should know that mercaptopurine may interfere with the normal menstrual cycle (period) in women and may stop sperm production in men. However, you should not assume that you cannot get pregnant or that you cannot get someone else pregnant. Women who are pregnant or breast-feeding should tell their doctors before they begin taking this drug. You should not plan to have children while receiving chemotherapy or for a while after treatments. (Talk to your doctor for further details.) Use a reliable method of birth control to prevent pregnancy. Mercaptopurine may harm the fetus.
do not have any vaccinations (e.g., measles or flu shots) without talking to your doctor.

Side effects

Side effects from mercaptopurine are common and include:

headache
weakness or achiness
darkening of the skin
loss of appetite or weight

Tell your doctor if either of these symptoms is severe or lasts for several hours:

mouth blistering
fatigue

If you experience any of the following symptoms, call your doctor immediately:

painful urination or red urine
black, tarry stools
diarrhea
pain in the abdomen
unusual bruising or bleeding
shortness of breath
swelling of the feet or legs
cough
fever
sore throat
nausea and vomiting
rash
yellowing of the skin or eyes
joint pain

Special instructions

Drink plenty of fluids. Drink about 10 eight-ounce glasses of fluid and urinate frequently during the first 24 hours after treatment to keep your kidneys working.
The most common side effect of mercaptopurine is a decrease in the number of blood cells. Your doctor may order tests before, during, and after your treatment to see if your blood cells are affected by the drug.

Last Revised - 01/01/2003

American Society of Health-System Pharmacists, Inc. Disclaimer