Carbamazepine is used in medicine as an agent for the prevention and treatment of neurological disorders. Most notably, it is used for the prophylaxis of seizures. The active ingredient is frequently prescribed in Germany.
What is carbamazepine?
Carbamazepine is used in medicine as an agent for the prevention and treatment of neurological disorders. Most notably, it is used for the prophylaxis of seizures. Carbamazepine is a substance called anticonvulsant. Anticonvulsants are drugs used to treat and prevent epileptic seizures. Chemically, it is classified in the class of dibenzazepines. It resembles the structure of the substance imipramine. Synonymous names for carbamazepine are 5H-dibenz[b,f]azepine-5-carbamide, 5H-dibenzo[b,f]azepine-5-carboxamide, and carbamazepinum. The molecular formula of the substance is C15H12N2O. For processing, carbamazepine is present as a white or nearly white crystalline powder. It is polymorphic, which means that it can occur in different forms. The physical state is solid. Carbamazepine is very slightly soluble in water. It is slightly soluble in dichloromethane and sparingly soluble in acetone and ethanol 96%.
Pharmacological action
The substance carbamazepine acts in the human body by blocking sodium channels located in the axons of nerve cells. The exact mechanism of action has not yet been conclusively determined. The active ingredient is absorbed relatively slowly in a period of 6 to 8 hours after ingestion. The bioavailability is 80%. The therapeutic range of carbamazepine is narrow. Consequently, accurate dosing is important to achieve the desired effect on the one hand, but to avoid overdose on the other. Attention must be paid to the correct dose and strictly regular intake of the drug. Carbamazepine is metabolized in the human body in the liver. Processing occurs via enzymes of the cytochrome P450 system. Carbamazepine induces the enzyme system. Mainly the substance is metabolized in the enzyme CYP3A4. Since numerous drugs are metabolized via the cytochrome P450 enzyme system, this is a potential risk for the development of interactions of carbamazepine with other drugs. When carbamazepine is metabolized in the body, carbamazepine-10,11-epoxide is formed as a secondary product. This substance also has anticonvulsant activity. However, it is also thought to be responsible for side effects of the drug.
Medical application and use
In medicine, carbamazepine is used as a drug to treat various neurological disorders. It is available only on prescription in Germany. The drug is used to treat and prevent various forms of epilepsy. It is used for focal seizures. These are seizures that originate in a circumscribed area of the brain. Carbamazepine is used to treat both simple partial seizures (without loss of consciousness) and complex partial seizures (with loss of consciousness). Generalized epileptic seizures affect both hemispheres of the brain. Carbamazepine is also used for these. The drug is also used for mixed forms of epilepsy. Another area of application for the drug is trigeminal neuralgia. This is seizure-like facial pain that originates from the facial trigeminal nerve. In glossopharyngeal neuralgia, patients suffer from pain in the throat. This condition can also be treated with carbamazepine. Diabetic polyneuropathy is a secondary disease of diabetes and another area of application for the active ingredient. Carbamazepine is also used to treat symptoms of multiple sclerosis such as dysesthesias, pain, and speech or movement disorders. Another area of use is the prevention of epileptic seizures in the context of alcohol withdrawal. In manic-depressive disorders, the drug is used to prevent episodes of the disease. Carbamazepine is available in tablet form. Depending on the dose and dosage form, it can be used in adults and children.
Risks and side effects
Often, taking carbamazepine causes dizziness, fatigue, drowsiness, as well as movement disorders. Also common may be nausea, vomiting, and loss of appetite. Carbamazepine may cause hypersensitivity reactions with rash, fever, and general symptoms. Severe allergic reactions including anaphylactic shock are very rare.Serious to life-threatening skin reactions have been reported in isolated cases in connection with the use of carbamazepine. The intake of carbamazepine can lead to blood count changes, which are usually harmless. Very rarely, severe courses are also possible. The active substance can cause water retention in the tissues. Laboratory parameters such as electrolytes, liver or thyroid values may be altered. Effects of the substance on the cardiovascular system with cardiac arrhythmias and influence on blood pressure may occur. Drug interactions may occur with simultaneous use of various other drugs, especially those with neurological effects. Simultaneous consumption of grapefruit juice and carbamazepine may affect the plasma level of the drug, i.e. the absorption of the drug into the blood. The drug should never be taken together with alcohol. This presentation is not a complete description of all possible side effects and interactions.
