How the interaction occurs:
When these two medicines are taken together, your body may not process your corticosteroid properly. The corticosteroid may also change the amount of the hydantoin (e.g. phenytoin) in your body.
What might happen:
The beneficial effects of your corticosteroid may decrease.In some patients, the amount of phenytoin in the blood may increase. This may result in more side effects than normal. In other patients, the amount of phenytoin in the blood may decrease and it may not work as well.
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.It may be necessary to monitor your hydantoin blood levels more frequently.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 before checking with them first.
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