Theophylline/Barbiturates; Hydantoins 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:

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 process theophylline more quickly.

What might happen:

The blood level of your theophylline may decrease, so it may not work as well.

What you should do about this interaction:

Let your healthcare professionals know you are taking these medicines together. If your doctor prescribes these two medicines together, you may need your theophylline level checked to be sure you are receiving the right dose.If you have been medicines together on a regular schedule, and then the barbiturate (e.g. phenobarbital) or hydantoin (e.g. phenytoin) is stopped by your doctor, your may also need to have your theophylline level checked to make sure you are at a safe and effective dose.If you experience problems with your breathing, severe nausea/vomiting, tremors, heart palpitations or other effects, 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 drug interaction and may be monitoring you for it. Do not start, stop, or change the dosage of any medicine before checking with them first.

View Reference
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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.