Methotrexate; Pralatrexate/Sulfonamides; Trimethoprim Interactions

This information is generalized and not intended as specific medical advice. Consult your healthcare professional before taking or discontinuing any drug or commencing any course of treatment.

Medical warning:

Serious. These medicines may interact and cause very harmful effects. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

When these two medicines are taken together, your body may not process methotrexate or pralatrexate properly.

What might happen:

Your blood levels of methotrexate or pralatrexate may increase and cause easy bruising or bleeding, persistent sore throat or fever, or fatigue. These effects are more likely if you are taking a high dose of methotrexate, such as those used in the treatment of cancer or psoriasis.

What you should do about this interaction:

Make sure your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together.If you experience swelling or soreness of the mouth or tongue, easy bruising or bleeding, persistent sore mouth or fever, or unusual fatigue, contact your doctor.Your healthcare professionals may already be aware of this interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.

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CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.