Used primarily as an anticonvulsant and mood-stabilizing agent in the treatment of epilepsy and bipolar disorder. It helps control certain types of seizures, including partial seizures and generalized tonic-clonic seizures, and is effective in reducing the frequency of seizure episodes. In bipolar disorder, it is used to delay mood episodes such as depression or mania, particularly showing benefit in preventing depressive phases. It is also sometimes used off-label for treatment-resistant depression and certain neuropathic pain conditions. Its mechanism involves stabilizing neuronal membranes by inhibiting voltage-dependent sodium channels, thereby reducing the release of excitatory neurotransmitters like glutamate.