Severe. These medicines may interact and cause very harmful effects and are usually not taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.
How the interaction occurs:
Carbamazepine may increase how quickly your body processes nefazodone. Nefazodone may decrease how quickly your body processes carbamazepine.
What might happen:
The amount of nefazodone in your blood may decrease and it may not work as well for your condition. The amount of carbamazepine in your blood may increase and cause side effects, including drowsiness, dizziness, blurred vision, or loss of coordination.
What you should do about this interaction:
Contact your healthcare professionals (e.g. doctor or pharmacist) as soon as possible about taking these medicines together. If your nefazodone is not working, your doctor may want to change your medication. Your doctor may want to check the amount of carbamazepine in your blood. Let your healthcare professionals know if you have any side effects from your carbamazepine. Your doctor may need to change your dose of carbamazepine.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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