Used primarily as an anticonvulsant medication to control seizures, especially in epilepsy. It works by stabilizing electrical activity in the brain, particularly by blocking voltage-dependent sodium channels, which reduces abnormal neuronal firing. Commonly prescribed for tonic-clonic and complex partial seizures. Also utilized in managing certain types of arrhythmias and neuropathic pain in some cases. Its long half-life allows for once or twice-daily dosing, making it suitable for chronic treatment. Monitoring of blood levels is often required due to nonlinear metabolism and potential toxicity.