Anticonvulsant

Anticonvulsants, also known as antiepileptic drugs (AEDs), are medications used primarily to prevent or control epileptic seizures. They are also employed for other conditions such as neuropathic pain and mood stabilization in bipolar disorder. They act by modulating neuronal excitability through diverse mechanisms and pharmacokinetics.

Most anticonvulsants exert their effects by one or more mechanisms: reduction of neuronal excitation via blockade or modulation of voltage-gated sodium channels (for example phenytoin, carbamazepine, lamotrigine, valproate); enhancement of inhibitory GABA neurotransmission (such as phenobarbital, benzodiazepines like diazepam, valproate); inhibition of T-type calcium channels (ethosuximide); and effects on other neurotransmitter systems including glutamate receptors. Newer agents include levetiracetam, topiramate, oxcarbazepine, and gabapentin/pregabalin, each with distinct pharmacology.

Indications include maintenance therapy for various epilepsy syndromes, treatment of status epilepticus in acute settings, and off-label uses such as migraine prophylaxis (topiramate), neuropathic pain (gabapentin, pregabalin), and mood stabilization (valproate, lamotrigine).

Safety and monitoring considerations cover a range of adverse effects from dizziness, sedation, and cognitive slowing to rash, liver injury, and teratogenic risks (notably valproate). Drug interactions and hepatic metabolism are important, with some agents requiring serum level monitoring. Discontinuation should be gradual to minimize withdrawal seizures, and ongoing assessment of efficacy and safety is standard during long-term use.