Mercaptopurine
About Mercaptopurine
Mercaptopurine is an oral prescription medication used primarily to treat acute lymphoblastic leukaemia, a type of blood cancer. It belongs to a group of medicines that work by slowing down or stopping the growth of abnormal cancer cells in the body. By controlling these abnormal cells, the medication helps patients achieve or maintain remission.
You should take this medicine exactly as prescribed by your doctor, typically once a day at the same time. It is crucial to take it consistently either always with food or always on an empty stomach to keep the level of medicine in your body steady. Some evidence suggests that taking milk or other dairy products close to your dose may reduce the absorption of mercaptopurine in some patients. Follow your prescribing doctor's or pharmacist's specific instructions regarding the timing of dairy products in relation to your medication.
While taking this medicine, some people may experience common side effects like nausea, mild stomach pain, or temporary hair thinning. However, you must contact your doctor immediately if you experience serious side effects, such as signs of an infection, unexplained bruising, or yellowing of your eyes and skin.f
Do not take this if you have had a severe allergic reaction to it in the past. Before starting, talk to your doctor if you have kidney disease, liver disease, or genetic variations affecting TPMT or NUDT15, which influence how your body processes this medication. Testing for TPMT and NUDT15 variants is now recommended in many treatment guidelines, particularly because NUDT15 variants are more common in Asian populations, including Indians. Your doctor may arrange these tests before treatment to help determine the safest starting dose.
Certain medications, such as gout treatments, can dangerously increase the levels of Mercaptopurine in your body, so always share a complete list of your medicines with your pharmacist. Avoid drinking alcohol while on this treatment, as it can increase your risk of liver damage. Pregnant or breastfeeding women should not take this medicine due to the risk of harm to the baby, and elderly individuals may require close monitoring of kidney function.
Uses of Mercaptopurine
Medicinal Benefits
Mercaptopurine helps manage certain cancers and autoimmune conditions by slowing the growth of abnormal cells and reducing excessive immune activity. By controlling the underlying disease, it supports long-term health and improves quality of life.
- Helps Maintain Remission in Leukaemia: By preventing the growth and multiplication of abnormal blood cells, Mercaptopurine helps keep leukaemia under control, allowing healthy blood cell production to recover and supporting long-term remission.
- Supports the Management of Inflammatory Bowel Disease: By suppressing an overactive immune response in the digestive tract, Mercaptopurine helps reduce inflammation, relieving symptoms such as abdominal pain, diarrhoea, and flare-ups.
- Promotes Better Long-Term Disease Control: With regular use as prescribed, Mercaptopurine helps reduce disease activity, lowers the risk of relapse, and supports improved daily functioning and overall wellbeing.
Directions for Use
- Mercaptopurine can be taken with or without food as advised by your doctor.
- Follow your doctor’s instructions on the dosage and timing of this medication.
- Swallow Mercaptopurine as a whole with a glass of water.
- Do not crush, break, or chew it.
Storage
Side Effects of Mercaptopurine
Common Side Effects (Usually mild):
- Nausea or vomiting
- Mild stomach pain or loss of appetite
- Temporary hair thinning
- Mild fatigue or feeling run down
Serious Side Effects (Consult a doctor right away):
- Signs of infection, such as fever, chills, sore throat, or mouth sores
- Unusual bruising, pinpoint red spots on your skin, or bleeding that does not stop
- Signs of liver damage, including yellowing of the skin or eyes, dark urine, or severe abdominal pain
- Severe allergic reactions, such as hives, swelling of the face or throat, or trouble breathing
- Extreme weakness, dizziness, or pale skin
Medicines Containing this Salt
View AllDrug Warnings
- Get regular blood tests: Your doctor will need to check your blood counts and liver function frequently to ensure the medicine is working safely.
- Wear gloves when handling: Caregivers should avoid direct skin contact with the tablets by wearing disposable gloves, especially if a tablet is broken or damaged.
- Avoid live vaccines: Do not receive live vaccines (such as the measles, mumps, rubella, or shingles vaccines) while taking this medicine, as your weakened immune system may not handle them well.
- Use effective birth control: Both men and women should use highly reliable birth control during treatment and for a period after stopping, as this medicine can cause severe birth defects.
- Watch for signs of bleeding: Use a soft toothbrush and electric razor to avoid cuts, as your body may bruise or bleed more easily.
Drug Interactions
- Allopurinol or febuxostat: Taking these gout medications with Mercaptopurine can dangerously increase the amount of this medicine in your blood, raising the risk of severe side effects. Your doctor will need to significantly lower your dose of Mercaptopurine if you must take these together.
- Warfarin: This medicine may decrease the blood-thinning effect of warfarin, meaning your doctor will need to monitor your blood clotting times more closely.
- Sulfasalazine or olsalazine: Taking these medicines alongside Mercaptopurine can increase the risk of bone marrow damage, leading to lower blood cell counts.
Drug-Drug Interactions Checker List:
Safety Advice
Alcohol
cautionInteraction of Mercaptopurine with alcohol is unknown. Please consult a doctor before consuming alcohol while using Mercaptopurine.
Pregnancy
unsafeMercaptopurine is a category D pregnancy drug and is not recommended for use during pregnancy, especially in the first 3 months as it may cause harm to the foetus. Please consult a doctor if you are pregnant or planning for pregnancy.
Breast Feeding
unsafeMercaptopurine is contraindicated in breastfeeding women. Please consult a doctor if you are breastfeeding.
Driving
safe if prescribedMercaptopurine usually does not affect your ability to drive or operate machinery.
Liver
cautionTake Mercaptopurine with caution, especially if you have a history of Liver diseases/conditions. The dose may be adjusted by your doctor as required.
Kidney
cautionTake Mercaptopurine with caution, especially if you have a history of Kidney diseases/conditions. The dose may be adjusted by your doctor as required.
Children
cautionMercaptopurine should be used with caution in children, especially in children below 6 years or with low body mass index as it may cause low blood sugar.
Habit Forming
Diet & Lifestyle Advise
- Avoid dairy near dosing times: Some evidence suggests that milk and dairy products may reduce the absorption of mercaptopurine when taken at the same time. Follow the timing instructions provided by your doctor or pharmacist regarding dairy intake around your dose.
- Practice strict hygiene: Wash your hands frequently with soap and water, avoid crowds, and stay away from people who are sick, as this medicine lowers your body's ability to fight off infections.
- Stay well-hydrated: Drink plenty of water throughout the day to support your kidneys as they process and eliminate the medication.
- Protect your skin from the sun: This medication can make your skin more sensitive to sunlight, so wear protective clothing and use sunscreen when outdoors.
Special Advise
Regular blood and urine tests are recommended while taking Mercaptopurine to monitor the number of red blood cells, platelets, white blood cells, uric acid levels, kidney or liver functioning.
Do not receive any vaccination during treatment without your doctor's approval while taking Mercaptopurine.
Patients Concern
Disease/Condition Glossary
Blood cancer: It is the cancer of blood cells, also known as leukaemia. It causes excessive production of immature white blood cells by the bone marrow. The symptoms include unintentional weight loss, weakness, excessive sweating, tiredness, bone pain, frequent infections, chills or fever, red spots on the skin or painless, swollen lymph nodes, especially in the armpits neck. The risk factors of leukaemia include smoking, genetic or blood disorders, family history of leukaemia, exposure to high radiation levels, or previous cancer treatment with radiation or chemotherapy.
FAQs
Mercaptopurine is used to treat acute lymphoblastic leukaemia (blood cancer).
Mercaptopurine contains Mercaptopurine that works by interfering with the production of genetic material (DNA and RNA) in the cancer cells that are essential for growth, repair and multiplication of cells. Thus, Mercaptopurine stops multiplication of abnormal cells and leads to the growth of cells in an unbalanced way and causes the death of cells.
Mercaptopurine may affect eggs or cause low sperm count. Therefore, please consult a doctor before taking Mercaptopurine if you are planning to become parents.
Mercaptopurine may increase sensitivity to sunlight or UV light. Therefore, avoid or limit exposure to the sun for a long time or artificial light such as tanning beds. Wear protective clothing and use a sunscreen before going out in the sun.
Mercaptopurine may cause low blood sugar levels in children below 6 years and those having low body weight. Therefore, use Mercaptopurine with caution in children and if you notice any symptoms such as dizziness, excessive sweating, confusion or nausea, please consult a doctor immediately.
If you are about to receive any vaccinations especially live vaccines such as measles vaccine, flu vaccine, BCG vaccine, etc., it is advised to inform your doctor that you are on treatment with Mercaptopurine as it may cause infections.
Mercaptopurine may increase the risk of infections. Therefore, consult your doctor if you notice any signs of infection such as urinary problems, chills, fever, cough, sore throat or mouth and avoid contact with people having cold, flu or infection.
Yes, Mercaptopurine is a chemotherapy drug. It belongs to the class of anticancer medications used to treat blood cancer (leukaemia), a condition in which the bone marrow produces excessive immature white blood cells. It works by inhibiting the production of DNA and RNA in cancer cells, which are essential for their growth and division. By disrupting this process, it prevents abnormal cells from multiplying, ultimately leading to their death.
Yes, Mercaptopurine may cause thrombocytopenia (low platelet count) as a side effect. This occurs due to its myelosuppressive effects, which suppress bone marrow activity. Therefore, regular monitoring of blood counts is advised during treatment with Mercaptopurine.
The side effects of Mercaptopurine include nausea, vomiting, loss of appetite, low red blood cell count, diarrhoea or inflammation of the mouth. Most of these side effects gradually resolve over time. However, consult the doctor if any of these symptoms persist or worsen.
Take Mercaptopurine with or without food as your doctor advises, preferably 1 hour before or 2 hours after taking milk or dairy products. Swallow it with a glass of water. Do not break, crush, or chew it.
No, Mercaptopurine is not recommended for use during pregnancy, especially in the first 3 months, as it may cause harm to the foetus. Please consult a doctor if you are pregnant or planning for pregnancy.
Some evidence suggests that taking Mercaptopurine together with milk or other dairy products may reduce how well the medicine is absorbed. Follow the specific instructions provided by your doctor or pharmacist regarding whether you should separate dairy products from your dose.
If you develop a fever, chills, or any other signs of an infection, contact your doctor immediately. This medicine lowers your white blood cell count, making it harder for your body to fight infections, which can become serious very quickly. Talk to your doctor or pharmacist for guidance.
It is highly recommended to avoid alcohol while taking Mercaptopurine. Both alcohol and this medication can strain your liver, and combining them significantly increases the risk of severe liver damage. Talk to your doctor or pharmacist for more information.
Regular blood tests are essential because this medicine can lower your blood cell counts (white cells, red cells, and platelets) and affect your liver function. These tests allow your doctor to adjust your dose safely before any serious complications arise. Talk to your doctor or pharmacist about your test schedule.
Yes, mild or temporary hair thinning can occur while taking Mercaptopurine, though complete hair loss is less common than with other chemotherapy drugs. Your hair will typically grow back once the treatment is stopped. Talk to your doctor or pharmacist if this is a concern for you.
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