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What should I discuss with my healthcare provider before taking mercaptopurine (Purinethol)?

You should not use mercaptopurine if you are allergic to it, or if you have ever used mercaptopurine or thioguanine (Tabloid) and they were not effective in treating your condition.

However, people with autoimmune disorders (including rheumatoid arthritis, Crohn's disease, ankylosing spondylitis, and psoriasis) may have a higher risk of lymphoma. Talk to your doctor about your individual risk.

To make sure you can safely take mercaptopurine, tell your doctor if you have any of these other conditions:

• liver disease;
• kidney disease; or
• any type of viral, bacterial, or fungal infection.

FDA pregnancy category D. Do not use mercaptopurine if you are pregnant. It could harm the unborn baby. Use effective birth control, and tell your doctor if you become pregnant during treatment.

It is not known whether mercaptopurine passes into breast milk or if it could harm a nursing baby. You should not breast-feed while taking mercaptopurine.

How should I take mercaptopurine (Purinethol)?

Take exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

Your doctor may occasionally change your dose to make sure you get the best results.

Mercaptopurine can lower blood cells that help your body fight infections. Your blood cells, kidney function, and liver function may need to be tested often. Your cancer treatments may be delayed based on the results of these tests. Do not miss any follow up visits to your doctor for blood or urine tests.

Store at room temperature away from moisture and heat.

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