Nintoin 100 mg is a medication that contains phenytoin sodium as its active ingredient. It is primarily used as an anticonvulsant to manage and prevent seizures in conditions such as epilepsy. Phenytoin works by stabilizing neuronal membranes and decreasing seizure activity in the brain by influencing sodium channels, thus preventing abnormal electrical activity. Nintoin 100 mg is usually prescribed for the control of generalized tonic-clonic (grand mal) and complex partial seizures. It may also be used to prevent seizures during or after neurosurgery. As with all antiepileptic medications, it should be taken exactly as prescribed by a healthcare provider, and regular monitoring may be required to ensure therapeutic levels and avoid potential side effects.