Mercaptopurine (By mouth)
Used in combination with other medicines as maintenance treatment of acute lymphatic leukemia. This medicine is also known as 6-MP.
There may be other brand names for this medicine.
When This Medicine Should Not Be Used
You should not use this medicine if you have had an allergic reaction to mercaptopurine or thioguanine, or if you have been treated with mercaptopurine or thioguanine and did not work well. Do not use this medicine if you are pregnant.
How to Use This Medicine
- Medicines used to treat cancer are very strong and can have many side effects. Before receiving this medicine, make sure you understand all the risks and benefits. It is important for you to work closely with your doctor during your treatment.
- Your doctor will tell you how much of this medicine to use and how often. Do not use more medicine or use it more often than your doctor tells you to.
- Drink extra fluids so you will pass more urine while you are using this medicine. This will keep your kidneys working well and help prevent kidney problems.
If a dose is missed:
- If you miss a dose or forget to use your medicine, use it as soon as you can. If it is almost time for your next dose, wait until then to use the medicine and skip the missed dose. Do not use extra medicine to make up for a missed dose.
How to Store and Dispose of This Medicine
- Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
- Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any leftover medicine after you have finished your treatment. You will also need to throw away old medicine after the expiration date has passed.
- Keep all medicine away from children and never share your medicine with anyone.
Drugs and Foods to Avoid
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.
- Make sure your doctor knows if you are also using allopurinol (Zyloprim®), cotrimoxazole (Bactrim®, Cotrim®, Septra®), mesalamine (Asacol®, Rowasa®), olsalazine (Dipentum®), sulfasalazine (Azulfidine®), or a blood thinner (such as warfarin, Coumadin®).
- Talk to your doctor before getting flu shots or other vaccines while you are receiving this medicine. Vaccines may not work as well, or they could make you ill while you are using this medicine.
Warnings While Using This Medicine
- Your unborn baby could be harmed if you use this medicine while you are pregnant. Use an effective form of birth control to keep from getting pregnant. Tell your doctor right away if you think you have become pregnant while using the medicine.
- Make sure your doctor knows if you are breastfeeding, or if you have kidney disease, liver disease, bowel problems (such as nausea, vomiting or diarrhea), blood or bone marrow problems (such as anemia, low white blood cells, or low platelets in the blood), gout, or any type of infection.
- Do not use this medicine if you or your child are also taking azathioprine (Imuran®). Using these medicines together could cause serious unwanted effects.
- This medicine may increase your risk of getting certain types of cancer. Some teenagers and young adults with Crohn's disease or ulcerative colitis developed a rare type of cancer called hepatosplenic T-cell lymphoma (HSTCL). Talk with your doctor if you or your child have unusual bleeding, bruising, or weakness; swollen lymph nodes in the neck, underarms, or groin; or unexplained weight loss.
- This medicine lowers the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. To help with these problems, avoid being near people who are sick or have infections. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.
- Stop using this medicine and check with your doctor right away if you or your child have pain or tenderness in the upper stomach; pale stools; dark urine; loss of appetite; nausea; unusual tiredness or weakness; or yellow eyes or skin. These could be symptoms of a serious liver problem.
- Do not stop taking this medicine without checking first with your doctor.
- Your doctor will need to check your blood at regular visits while you are using this medicine. Be sure to keep all appointments.
Possible Side Effects While Using This Medicine
Call your doctor right away if you notice any of these side effects:
- Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
- Bloody or black, tarry stools.
- Dark-colored urine or pale stools.
- Nausea, vomiting, diarrhea, loss of appetite, or pain in the upper stomach.
- Severe pain or swelling in your joints.
- Unexplained fever, chills, or sore throat.
- Unusual bleeding, bruising, or weakness.
- Yellowing of your skin or the whites of your eyes.
If you notice these less serious side effects, talk with your doctor:
- Darkening of skin color.
- Hair loss.
- Mild diarrhea.
- Mild skin rash.
If you notice other side effects that you think are caused by this medicine, tell your doctor
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088
- Last Reviewed on 06/12/2013
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This page was last updated: June 18, 2013