Mercaptopurine (also known as 6-mercaptopurine or 6-MP) is used for acute lymphoblastic leukemia (ALL). It’s typically taken together with other anticancer medications. Mercaptopurine is also commonly used off-label for certain gut problems (Crohn’s disease and ulcerative colitis). This medication is taken by mouth as a tablet or an oral suspension. While the tablet is only available as a generic, the oral liquid is only available under the brand name Purixan. Mercaptopurine has unpleasant side effects, like low appetite, stomach upset, and feeling unwell.
Acute lymphoblastic leukemia (ALL)
Mercaptopurine is a type of antimetabolite medication called a nucleoside metabolic inhibitor. It stops cancer cells from being able to make their own genetic material. This kills cancer cells and stops cancer growth.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Black, tarry stools
bleeding gums
clay colored stools
cough or hoarseness
dark urine
decreased appetite
fever or chills
headache
loss of appetite
lower back or side pain
nausea, vomiting
painful or difficult urination
pale skin
pinpoint red spots on the skin
rash, itchy skin
stomach pain or tenderness
swelling of the feet or lower legs
trouble with breathing upon exertion
unusual bleeding or bruising
unusual tiredness or weakness
yellow eyes or skin
Incidence not known
blurred vision
cold sweats
coma
confusion
dizziness
fast heartbeat
increased hunger
increased sensitivity of the skin to sunlight
indigestion
joint pain, stiffness, or swelling
nervousness
nightmares
redness or other discoloration of the skin
seizures
severe sunburn
shakiness
slurred speech
stomach cramping or burning
vomiting of blood or material that looks like coffee grounds
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
Darkening of the skin
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Taken by mouth once a day
Can use in children
Available as tablets, as well as an oral liquid for people who have trouble swallowing pills
Has a lot of side effects, such as low blood cell counts and stomach upset
Raises risk of infection
Requires regular blood tests during treatment to check for side effects and safety
Take mercaptopurine at the same time each day, with or without food. Make sure you're consistent — either choose to always take it on an empty stomach or with a meal. Food can change how much mercaptopurine gets absorbed into your body.
Wear protective clothing and sunscreen to protect your skin from the sun. Mercaptopurine can make your skin more sensitive to the sun, which can raise your risk for getting sunburns more easily.
Be sure to wash your hands well with soap and warm water often and try to stay away from people who are ill. Mercaptopurine can weaken your immune system, which can raise your risk of infections.
Before getting any vaccines, let your provider know that you’re taking mercaptopurine. This medication can weaken the immune system, which can affect how well vaccines work or affect how safe certain vaccines are for you. Your provider can make sure the vaccines you’re planning to get are appropriate for you.
If you or your partner is able to become pregnant, use birth control while you’re taking mercaptopurine. Continue to use birth control for 3 months (for men) or for 6 months (for women) after you stop the medication. can cause harm to an unborn baby. Let your provider know if you or your partner becomes pregnant during treatment.
Ask your provider or pharmacist about how handle and throw away any leftover mercaptopurine safely. This medication can be harmful to others. Don’t place it in your household trash or pour it down the sink.
Tips for the mercaptopurine oral liquid (Purixan)
Follow your provider's directions to measure and take your dose. You can also watch the instructional video to review how to use Purixan. Ask your provider or pharmacist if you're not sure how to take the oral liquid.
Shake the bottle for at least 30 seconds before each use to make sure it's mixed well. Then, use the provided press-in bottle adapter and oral syringes to measure and take mercaptopurine. Don't use household measuring or kitchen spoons since they might not be accurate and cause you to take the wrong amount of medication.
After taking your mercaptopurine dose, drink some water to make sure you've swallowed all of the medication in your mouth.
Keep Purixan at room temperature. It’s good to use for 8 weeks. Throw away any leftover medication after 8 weeks.
Mercaptopurine can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Taking allopurinol (Zyloprim), mesalamine, or sulfasalazine (Azulfidine) | Taking other medications that suppress the bone marrow
Mercaptopurine causes your bone marrow to make fewer blood cells (bone marrow suppression). As a result, your red blood cell count can drop, leading to anemia. Your white blood cell count can also fall, which raises your risk of infection and affects how well your body can fight them off. In addition, your platelet count can get too low and put you at risk of bleeding. Your risk of these effects might be higher if you also take allopurinol (Zyloprim), mesalamine, or other medications that also suppress the bone marrow.
Your provider will check your blood cell counts through blood tests during treatment with mercaptopurine. If your blood cell counts become too low, they might lower your dose. Let your provider know if you feel very tired, get sick often, or have unusual bleeding or bruising while you’re taking mercaptopurine. These can be signs that your blood cell counts are too low.
Risk factors: Taking higher than recommended doses of mercaptopurine | Taking other medications that can cause liver problems | History of liver disease
Mercaptopurine can damage your liver, which can be fatal in severe cases. One symptom of liver damage, yellowing of the skin or eyes (jaundice), usually happens within the first 2 months of starting the medication. But, it can also happen at any time while you’re taking mercaptopurine. Make sure you get your blood drawn regularly during treatment so your provider can check your liver health. Report any symptoms of liver problems, such as yellowing of the skin or eyes, dark urine, pale stools, loss of appetite, diarrhea, and stomach bloating. You might need to stop taking mercaptopurine.
Risk factors: Taking multiple medications that can weaken the immune system
There’s a higher risk that you might develop new cancers while you’re taking mercaptopurine. These new cancers might include other blood cancers or skin cancers. It appears that this risk is related to how much and for how long your immune system has been weakened by mercaptopurine and your other immune-suppressing medications. Speak with your provider if you’re concerned about this risk with mercaptopurine treatment.
Mercaptopurine can cause harm to the unborn baby when it’s taken during pregnancy. Some women who’ve taken the medication during the first trimester of pregnancy have reported miscarriage (pregnancy loss) and stillbirth. Because of this risk, both men and women who can have children should use birth control during treatment with mercaptopurine. After you stop the medication, continue to use birth control for 3 more months (for men) or 6 more months (for women). Let your provider know if you or your partner becomes pregnant while you’re taking mercaptopurine.
Dosage | Quantity | Price as low as | Price per unit |
---|---|---|---|
50mg | 90 tablets | $63.57 | $0.71 |
This medication is available as generic tablets and a brand-name oral liquid called Purixan.
The starting dose is based on your body weight, so your provider will help determine the right dose for you. The recommended starting dose is 1.5 mg/kg to 2.5 mg/kg of weight by mouth once a day.
Your dose might differ if you have side effects (e.g., severely low blood cell counts) or if you take allopurinol (Zyloprim).
Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Acute lymphoblastic leukemia (ALL); given with other chemotherapy
Treatment and prevention of meningeal leukemia
Non-Hodgkin lymphoma (NHL)
Osteosarcoma; given with other chemotherapy
Breast cancer; given with other chemotherapy
Gestational trophoblastic neoplasia (GTN); given with other chemotherapy
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