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Camptosar intravenous

Interactions

Irinotecan/St. John's Wort

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:

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:

St. John's wort may speed up how quickly your liver processes irinotecan.

What might happen:

The amount of irinotecan in your blood may decrease and it may not work as well.

What you should do about this interaction:

Let your healthcare professionals (e.g. doctor or pharmacist) know right away if you have been taking St. John's wort. Your doctor may want you to stop taking St. John's wort for two weeks before and during your irinotecan therapy. Do not start taking St. John's wort during your irinotecan therapy. Do not stop taking St. John's wort while taking irinotecan without talking talking to your healthcare professionals.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.

References:

1.Camptosar (irinotecan hydrochloride) US prescribing information. Pharmacia & Upjohn Company May, 2010.

2.Mathijssen RHJ, Verweij J, De Bruijn P, De Jonge MJA, Sparreboom A. Modulation of irinotecan (CPT-11) metabolism by st. john's wort cancer patients. 93rd Annual Meeting of the American Association for Cancer Research, San Francisco, CA 2002 Apr 8.

3.Mathijssen RH, Verweij J, de Bruijn P, Loos WJ, Sparreboom A. Effects of St. John's wort on irinotecan metabolism. J Natl Cancer Inst 2002 Aug 21; 94(16):1247-9.

Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, expect as may be authorized by the applicable terms of use.

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.

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