Topamax Drug Interactions

Topamax can decrease the level of lithium in your blood, perhaps making it less effective. Your healthcare provider may need to monitor the level of lithium in your blood and adjust your lithium dosage as necessary, especially when starting or stopping Topamax.

 

Topamax can increase the level of metformin in your blood, increasing your risk of side effects. Your healthcare provider may need to monitor you more closely and adjust your metformin dose as necessary.

 

Studies of a drug interaction between Topamax and oral contraceptives have shown conflicting results. Some studies have shown no interaction, while others have shown that Topamax may decrease the level of the oral contraceptive in your blood, especially at higher doses. Be sure to discuss this with your healthcare provider. You may need to use a different form of birth control, depending on your Topamax dosage and the particular oral contraceptive.

 

Taking phenytoin with Topamax can increase the level of phenytoin in your blood and decrease the level of Topamax in your blood. Your healthcare provider may need to adjust your dose of these medications.

 

Topamax can decrease the level of pioglitazone in your blood, perhaps making it less effective. Your healthcare provider may need to increase your pioglitazone dose.

 

Topamax can decrease the level of risperidone in your blood, perhaps making it less effective. Your healthcare provider may need to increase your risperidone dose.