Author: Ms. Shikha Singh
Volume: 01
First Online: 31 August 2024
Pages: 220-248
DOI:

Anticonvulsants, also known as antiepileptic drugs (AEDs), are medications used to prevent and control seizures in various types of epilepsy. They are classified based on their chemical structure and mechanisms of action into several categories, including barbiturates, hydantoins, oxazolidinediones, succinimides, urea and monoacylureas, benzodiazepines, and miscellaneous agents. The structure-activity relationship (SAR) of anticonvulsants involves specific modifications to their core structures to enhance their efficacy and reduce toxicity. These drugs generally work by stabilizing neuronal membranes, inhibiting excitatory neurotransmission, or enhancing inhibitory neurotransmission. Barbiturates like phenobarbitone and methabarbital enhance GABAergic inhibition, while hydantoins such as phenytoin, mephenytoin, and ethotoin act by blocking voltage-gated sodium channels, preventing seizure propagation. Oxazolidinediones, including trimethadione and paramethadione, and succinimides like phensuximide, methsuximide, and ethosuximide, are effective in treating absence seizures by modulating T-type calcium channels. Urea derivatives such as phenacemide and carbamazepine inhibit sodium channels, with carbamazepine being widely used for various seizure types. Benzodiazepines like clonazepam enhance GABA activity, providing potent anticonvulsant effects. Miscellaneous agents like primidone, valproic acid, gabapentin, and felbamate have diverse mechanisms, including enhancing GABAergic activity and inhibiting excitatory neurotransmitters, making them versatile in treating different forms of epilepsy. These varied mechanisms and structural modifications underscore the complexity and effectiveness of anticonvulsant therapies.