A variety of anticonvulsants may be very effective in reducing migraine attacks.  The only anticonvulsant currently approved for migraine prophylaxis is valproate which has significant side effects such as weight gain, drowsiness, tremor, and hair loss.  Fetal abnormalities and hematologic and liver abnormalities are also noted.  The second anticonvulsant, which will be approved in 2004, is topiramate.  A small percentage of patients using topiramate experience cognitive side effects such as memory loss and mild confusion.  Other side effects include hair loss and peripheral tingling of the hands and feet.  Topiramate is also a potent appetite suppressor in approximately 50 percent of  individuals that take it and it is also a blocker of carbonic and hydrase which makes it a medication of choice in the headache of pseudotumor cerebri.  Levetiracetam is also an agent useful in the management of migraine.²⁶⁹  Levetiracetam is weight neutral and does not have significant cognitive side effects, although drowsiness is sometimes noted unless the dose is increased quite slowly.  Other anticonvulsants useful in the prevention of migraine include zonisamide and neurontin.