Pharmacology of Carbamazepine (Tegretol) ; Mechanism of action, Uses, Effects

Carbamazepine is an anticonvulsant and mood-stabilizing medication used primarily to treat epilepsy and bipolar disorder. Here's a brief overview of its pharmacology: Mechanism of Action Carbamazepine works by inhibiting voltage-sensitive sodium channels in the brain. This action stabilizes hyperexcited nerve membranes, inhibits repetitive neuronal firing, and reduces synaptic propagation of excitatory impulses2. Pharmacokinetics Absorption: Carbamazepine is well absorbed after oral administration, with peak plasma levels occurring 6-8 hours after ingestion. Distribution: It is widely distributed throughout the body and is about 70% bound to plasma proteins. Metabolism: The drug is metabolized in the liver to its active metabolite, carbamazepine-epoxide. It also induces its own metabolism, which can affect the levels of other drugs4. Excretion: Carbamazepine is excreted mainly in the urine, with a small amount excreted in the feces. Half-Life: The half-life of carbamazepine is initially around 36 hours but shortens to about 12 hours with chronic use. Indications Epilepsy: Used to treat various types of seizures, including generalized tonic-clonic seizures and partial seizures. Bipolar Disorder: Effective in treating manic and mixed episodes. Trigeminal Neuralgia: Used to manage pain associated with this condition. Side Effects Common side effects include dizziness, drowsiness, nausea, and vomiting. More serious side effects can include blood dyscrasias (e.g., aplastic anemia, agranulocytosis), liver dysfunction, and hypersensitivity reactions4. Drug Interactions Carbamazepine can interact with many other medications, either increasing or decreasing their effects. It is a potent inducer of cytochrome P450 enzymes, which can lead to reduced efficacy of other drugs metabolized by these enzymes #Carbamazepine