Purinethol (Mercaptopurine)

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Purinethol Brand
Dosage Quantity & Price
Mercaptopurine (Generic alternate to Purinethol) Generic
Dosage Quantity & Price
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Purinethol is a medication used to treat acute lymphoblastic leukemia, a type of cancer affecting the white blood cells. It contains the active ingredient mercaptopurine, which is an anti-cancer (antineoplastic) chemotherapy drug. Mercaptopurine works by interfering with DNA production, which stops cell growth and division, resulting in the death of cancer cells.

Purinethol is usually given orally once daily as part of a combination chemotherapy maintenance regimen. As with all potent drugs, it should be used only if a diagnosis of acute lymphoblastic leukemia has been adequately established and the potential benefits of the treatment outweigh the risks.

Use and Dosage

Purinethol tablets are taken orally with or without food, as directed by your doctor, usually once a day. While taking the tablet, drink plenty of fluids unless otherwise directed by your doctor, as this may help decrease the risk of certain side effects, such as kidney problems.

The dosage of the medication is based on your medical condition, weight, and response to treatment. To ensure maximum benefits from the medication, take the Purinethol tablet regularly at the same time every day. Do not increase your dose or use the medication more often or for longer than prescribed, as this can increase your risk of serious side effects.

Side Effects

Common Side Effects of Purinethol (Mercaptopurine):

  • Darkening of the skin
  • Hair loss
  • Nausea
  • Rash
  • Vomiting

Serious Side Effects of Purinethol (Mercaptopurine):

  • Diarrhea
  • Loss of appetite
  • Pain in the upper right part of the stomach
  • Pale skin
  • Shortness of breath
  • Sore throat, fever, chills, or other signs of infection
  • Swelling in the legs, ankles, or feet
  • Swelling of the stomach area
  • Unusual bruising or bleeding
  • Weakness
  • Yellowing of the skin or eyes

Forms and Strength

Purinethol (Mercaptopurine) is available in the following forms and strength:

Purinethol: Tablet

  • 50 mg

Mercaptopurine: Tablet

  • 50 mg


  • Risk of infection: Purinethol can lower the body's immune system, making the patient more susceptible to infections. Avoid contact with people who have infections or illnesses while taking Mercaptopurine.
  • Liver problems: Mercaptopurine may cause liver problems, especially in patients who already have liver disease. Regular monitoring of liver function is recommended during treatment with Purinethol.
  • Pancreatitis: Purinethol may cause inflammation of the pancreas, leading to abdominal pain, nausea, and vomiting. This condition requires immediate medical attention.
  • Genetic variation: There may be a genetic variation in some patients that can lead to purinethol toxicity.
  • Pregnancy and breastfeeding: Mercaptopurine should not be used by pregnant or breastfeeding women unless the benefits outweigh the risks.
  • Renal impairment: Purinethol may cause kidney damage, especially in patients who already have kidney disease. Regular monitoring of kidney function is recommended during treatment with Purinethol.
  • Bone marrow suppression: Purinethol can suppress bone marrow function, leading to low levels of white blood cells, red blood cells, and platelets. Regular blood tests are recommended to monitor blood cell counts during treatment with Purinethol.
  • Allergic reaction: Some patients may develop an allergic reaction to Purinethol, which can cause symptoms such as rash, itching, and difficulty breathing. If these symptoms occur, medical attention should be sought immediately.

Frequently Asked Questions (FAQ)

Can Purinethol (Mercaptopurine) be used during pregnancy or breastfeeding?

There is limited data on the safety of Purinethol during pregnancy and breastfeeding and it should be used with caution. Discuss the potential risks and benefits with your doctor before taking Purinethol during pregnancy or while breastfeeding.

Are there any drug interactions with Purinethol (Mercaptopurine)?

Yes, Purinethol may interact with other medications, including allopurinol, which can increase the risk of severe bone marrow suppression. Inform your doctor of all medications and supplements you are taking to avoid potential interactions.

Can Purinethol (Mercaptopurine) be used for the treatment of ulcerative colitis?

While Purinethol has been used in the treatment of Crohn's disease, it is not typically used for the treatment of ulcerative colitis.

What should I do if I experience side effects while taking Purinethol (Mercaptopurine)?

If you experience any side effects while taking Purinethol, notify your doctor as soon as possible. Depending on the severity and nature of the side effect, your doctor may adjust the dose or switch to a different medication.


It's important to purchase Purinethol from verified Canadian pharmacy.

Additional information

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Quantities Available:

25, 100