How the interaction occurs:
When these two medicines are taken together, folic acid and pyrimethamine may cause your body to not process the hydantoin (e.g. phenytoin) properly.
What might happen:
Your blood level of the hydantoin may decrease which may cause an increased chance of seizures.
What you should do about this interaction:
The blood level of your hydantoin may need to be monitored more often. The dose of your hydantoin may need to be adjusted.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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