Carbamazepine/Selected Calcium Channel Blockers 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:

Diltiazem and verapamil may slow down how quickly your liver processes carbamazepine.Carbamazepine may speed up how quickly your liver processes felodipine or lercanidipine.

What might happen:

If you are taking diltiazem or verapamil, the amount of carbamazepine in your blood may increase and cause toxic side effects.If you are taking felodipine or lercanidipine, the amount of felodipine or lercanidipine in your blood may decrease and it may not work well.

What you should do about this interaction:

Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. Your doctor may want to check the amount of your medicine in your blood. Your doctor may want you to check your blood pressure more often.If you experience changes in vision, restlessness, increased drowsiness, or if your blood pressure goes up , contact your doctor.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.