Drug Interactions With Phenytoin
The following sections explain in detail the potentially negative interactions that can occur when phenytoin is combined with any of the drugs listed above.
AlcoholAlcohol can interfere with the way your body handles phenytoin. Chronic alcohol intake can decrease the level of phenytoin in your blood, while short-term intake of a large amount of alcohol can increase the level of phenytoin in your blood. Be sure to discuss your drinking habits with your healthcare provider (see Dilantin and Alcohol for more information).
AmiodaroneAmiodarone can increase the amount of phenytoin in your blood, increasing your risk of side effects. Your healthcare provider may need to measure the level of phenytoin in your blood and adjust your dose as necessary.
AtorvastatinPhenytoin may decrease the level of atorvastatin in your bloodstream, perhaps making it less effective. While this is not a particularly dangerous interaction, your healthcare provider may want to monitor your cholesterol levels to make sure atorvastatin remains effective for you.
Calcium can interfere with the absorption of phenytoin into your bloodstream. Try not to take phenytoin and calcium products at the same time of the day.
Combining phenytoin with certain antifungal medications may increase the level of phenytoin in your bloodstream and may decrease the level of the antifungal. Check with your healthcare provider before taking these medications together.
Certain Seizure MedicationsSome seizure medications may increase the level of phenytoin in the blood, while others may decrease phenytoin levels. Some can interact with phenytoin unpredictably. In addition, phenytoin may make other seizure medications less effective. Always double-check with your healthcare provider before combining any seizure medications with phenytoin.