Table 1.

Combination of antiepileptic (AEDs) and non-antiepileptic (NEDs) drugs at risk for pharmacokinetic interactions

	Antiepileptic Drug (AED)
	phenytoin	carbamazepine	phenobarbital	valproate	topiramate	oxcarbazepine
Combinations affecting NEDs
High risk	warfarin	warfarin	warfarin	quetiapine
	quetiapine	simvastatin
		quetiapine
		mirtazapine
		risperidone
Medium risk	atorvastatin	citalopram	metoprolol	warfarin	digoxin	diltiazem
	mirtazapine	trazodone	levothyroxine		risperidone
	digoxin	levothyroxine
	levothyroxine
Risk probable but unspecified	simvastatin	sertraline	simvastatin			omeprazole
	furosemide	diltiazem	donepezil			clopidogrel
	sertraline	prednisone	carvedilol			donepezil
	diltiazem	escitalopram	quetiapine			atorvastatin
	prednisone					prednisone
	donepezil
Combinations affecting AEDs
Increased effect	omeprazole	diltiazem	omeprazole	sertraline	metoprolol
	clopidogrel	propoxyphene	propoxyphene
	warfarin	quetiapine
	sertraline	trazodone
	diltiazem	risperidone
	trazodone
	allopurinol
	nitrofurantoin
	risperidone
Decreased effect	quetiapine