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Synthroid

Interactions

Levothyroxine sodium/Orlistat

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:

Moderate. These medicines may cause some risk when taken together. Contact your healthcare professional (e.g. doctor or pharmacist) for more information.

How the interaction occurs:

Orlistat may decrease how well the levothyroxine works.

What might happen:

You may notice some symptoms of hypothyroidism, which include cold intolerance, feeling tired, dry skin, and constipation.

What you should do about this interaction:

Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. Separate the times you take your levothyroxine and your orlistat by at least four hours. Let your doctor know if you have any symptoms of hypothyroidism. Your doctor may want to check how your medicine is working with a blood test.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.Synthroid (levothyroxine sodium) US prescribing information. Abbott Laboratories June, 2011.

2.Tirosint (levothyroxine sodium) US prescribing information. Institut Biochimique SA (IBSA) December, 2007.

3.Xenical (orlistat) US prescribing information. Roche Laboratories, Inc. October, 2013.

4.Madhava K, Hartley A. Hypothyroidism in thyroid carcinoma follow-up: orlistat may inhibit the absorption of thyroxine. Clin Oncol (R Coll Radiol) 2005 Sep;17(6):492.

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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