How the interaction occurs:
Efavirenz and nevirapine may speed up how quickly your liver processes methadone.
What might happen:
The amount of methadone in your blood may decrease and it may not work as well.
What you should do about this interaction:
Let your healthcare professionals (e.g. doctor or pharmacist) know that you are taking these medicines together. Your doctor may want to change the dosage of your methadone. Let your doctor know if your methadone does not seem to be working as well or you have any symptoms of withdrawal.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.
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