Protease Inhibitors/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:

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:

Carbamazepine may increase how quickly your body processes your protease inhibitor. Indinavir and ritonavir may decrease how quickly your body processes carbamazepine.

What might happen:

If you take carbamazepine and the protease inhibitors amprenavir, fosamprenavir, indinavir, lopinavir, nelfinavir, or saquinavir together, the levels of the protease inhibitor in your blood may decrease and it may not work as well against your HIV infection.Indinavir and ritonavir may increase the levels of carbamazepine in your blood and cause toxicity.

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 test your blood to make sure that your medicine is working against your HIV infection. Your doctor may want to check the amount of carbamazepine in your blood. Let your doctor know if you experience any drowsiness, dizziness, blurred vision, or loss of coordination.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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  • 3.Agenerase (amprenavir) Oral Solution US prescribing information. GlaxoSmithKline May, 2005.
  • 4.Lexiva (fosamprenavir calcium) US prescribing information. GlaxoSmithKline March, 2019.
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  • 6.Viracept (nelfinavir mesylate) US prescribing information. Agouron Pharmaceuticals, Inc. September, 2016.
  • 7.Invirase (saquinavir mesylate) US prescribing information. Roche Laboratories, Inc. March, 2019.
  • 8.Norvir (ritonavir) US prescribing information. Abbott Laboratories December, 2019.
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  • 10.Prezista (darunavir) US prescribing information. Janssen Therapeutics March, 2023.
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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.