Purinethol

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Purinethol Prescription Drug Information

Mercaptopurine (By mouth)
Mercaptopurine (mer-kap-toe-PURE-een)

Treats leukemia.

Brand Name(s):Purinethol
There may be other brand names for Purinethol.

When Purinethol Should Not Be Used:
You should not use Purinethol if you have had an allergic reaction to mercaptopurine or thioguanine, or if you have ever been treated with mercaptopurine or thioguanine (Tabloid®) and the medicines did not work. You should not use mercaptopurine if you are pregnant.

How to Use Purinethol:
Tablet

• Your doctor will tell you how much of Purinethol 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 Purinethol. This will keep your kidneys working well and help prevent kidney problems.

If a dose of Purinethol 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 Purinethol:

• 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 While Taking Purinethol:
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 a blood thinner such as warfarin (Coumadin®), allopurinol (Zyloprim®), cotrimoxazole (Bactrim®, Septra®), olsalazine (Dipentum®), mesalamine (Asacol®), or sulfasalazine (Azulfidine®).
• Talk to your doctor before getting flu shots or other vaccines while you are receiving Purinethol. Vaccines may not work as well, or they could make you ill while you are using Purinethol.

Warnings While Using Purinethol:

• Using Purinethol while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. If you think you have become pregnant while using the medicine, tell your doctor right away.
• Make sure your doctor knows if you are breastfeeding, or if you have liver disease, kidney disease, gout, or inflammatory bowel disease.
• You should not use Purinethol if you are also taking azathioprine (Imuran®). Using these medicines together could cause serious health problems.
• Your doctor will need to check your blood or urine at regular visits while you are using Purinethol. Be sure to keep all appointments.
• Purinethol 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.

Possible Side Effects While Using Purinethol:
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, pain in the upper stomach.
• Severe pain or swelling in your joints.
• Unexplained fever, sore throat, chills.
• Unusual bleeding, bruising, or weakness.
• Yellowing of your skin or the whites of your eyes.

If you notice these less serious side effects while taking Purinethol, talk with your doctor:

• Darkening of skin color.
• Mild diarrhea.
• Mild skin rash.

If you notice other side effects that you think are caused by Purinethol, tell your doctor.
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088