Valproic Acid/Carbamazepine 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:

Moderate. These medicines may cause some risk when taken together. 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 process carbamazepine more slowly. You may also process valproic acid more quickly.

What might happen:

Your blood levels of carbamazepine may increase and cause toxic effects. Your blood levels of valproic acid may decrease and cause seizures.

What you should do about this interaction:

If you experience confusion, fever, tremors, mental or mood changes, weakness, seizures, or other symptoms, contact your doctor. It may be necessary to change your dose of one or both medicines. Your doctor may also want to measure your blood levels of these medicines more often.Your healthcare professionals (e.g. doctor or pharmacist) 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.