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Barbiturates/Corticosteroids (mono deleted 02/02/2012)

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:

When these two medicines are taken together, your body may not process your corticosteroid properly.

What might happen:

The beneficial effects of your corticosteroid may decrease.

What you should do about this interaction:

If you notice a change in your condition, contact your doctor. It may be necessary to adjust the dose of your medicine.Your healthcare professionals (e.g. doctor or pharmacist) 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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8.Hancock KW, Levell MJ. Primidone/dexamethasone interaction. Lancet 1978 Jul 8;2(8080):97-8.

9.Young MC, Hughes IA. Loss of therapeutic control in congenital adrenal hyperplasia due to interaction between dexamethasone and primidone. Acta Paediatr Scand 1991 Jan;80(1):120-4.

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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