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rifapentine

Interactions

Posaconazole/Rifamycins

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:

Rifamycin antibiotics may speed up how quickly your liver processes posaconazole. Posaconazole may slow down how quickly your liver processes rifabutin.

What might happen:

The amount of posaconazole in your blood may decrease and it may not work as well. If you are taking rifabutin, the amount of rifabutin in your blood may increase and cause toxic side effects.

What you should do about this interaction:

Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together or if you have recently taken any rifamycin antibiotic. Your doctor may want to adjust the dose of your antifungal medicine while you are taking your antibiotic and for a few weeks after you finish it or your doctor may want to change your medicine. Your doctor may also want to check the number of cells in your blood.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.Noxafil (posaconazole) UK summary of product characteristics. Schering-Plough Ltd. February 2, 2006.

2.Noxafil (posaconazole) US prescribing information. Merck & Co. Inc March, 2014.

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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