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.
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, the amount of felodipine 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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