I dont know enough of that specific drug to say if there is a pharmacokinetic reaction (like inhibiting or inducing enzymes involved in its metabolism) but can say this. A-php is a stimulant. Stims can increase your risks for the two things many antiepileptics treat, namely seizures and mental disease. Also, since many seizure drugs can cause sedation and the like, you may have less of a good stim trip. These would be examples of pharmacodynamic interactions that could be deadly.
What seizure drug are you taking? Lamictal isnt known for inhibiting or inducing enzymes ala Valproic Acid or phenobarb.