definition of Topamax (topiramate): Topamax® is an anticonvulsant that may be prescribed for people with autism to help reduce irritability and self-injuring behaviors. Topamax®can also help reduce seizures. Topamax® is indicated for reducing seizures in people with epilepsy for ages 2-years old and up; and also for preventing migraine headaches. Topamax is available as tablets and as sprinkle capsules that can be taken as a whole capsule or sprinkled on food. This medication may have a side effect of metabolic acidosis (the blood getting too acidic). People taking this medication need to be monitored closely by a medical professional and may require regular blood tests.