Anticonvulsant

n. drug used to prevent or lessen the occurrence of convulsions or seizures (Medicine)

adj. serving to prevent or lessen the occurrence of convulsions or seizures (Medicine)

The anticonvulsants, sometimes also called antiepileptics, belong to a diverse group of pharmaceuticals used in prevention of the occurrence of epileptic seizures. More and more, anticonvulsants are also finding ways into the treatment of bipolar disorder, since many seem to act as mood stabilizers. The goal of an anticonvulsant is to suppress the rapid and excessive firing of neurons that start a seizure. Failing this, a good anticonvulsant would prevent the spread of the seizure within the brain and offer protection against possible excitotoxic effects that may result in brain damage. However, anticonvulsants themselves have been linked to lowered IQ and cell apoptosis.
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Anticonvulsant /an·ti·con·vul·sant/ inhibiting convulsions, or an agent that does this. an·ti·con·vul·sant n. [more]Anticonvulsant - Community and Resources

Noun
1. a drug used to treat or prevent convulsions (as in epilepsy)
(synonym) anticonvulsant drug, antiepileptic, antiepileptic drug
(hypernym) medicine, medication, medicament, medicinal drug
(hyponym) ethosuximide, Emeside, Zarontin

noun & adjective
(drug) used to control convulsions, as in the treatment of epilepsy