Products
Clonazepam is commercially available as tablets, injectable solution, and oral drops (Rivotril). It has been approved in many countries since 1973. In the United States, it is marketed as Klonopin.
Structure and properties
Clonazepam (C15H10ClN3O3, Mr = 315.7 g/mol) exists as a faint yellowish crystalline powder that is practically insoluble in water. It is a 5-aryl-1,4-benzodiazepine bearing a nitro group. Clonazepam is a chlorinated derivative of nitrazepam (mogadone).
Effects
Clonazepam (ATC N03AE01) has anticonvulsant, depressant, and antianxiety properties. The effects are due to allosteric binding to the postsynaptic GABA receptor, opening of chloride channels, and potentiation of the effects of GABA, the major inhibitory neurotransmitter in the brain. Clonazepam has a long half-life between 30 to 40 hours.
Indications
For the treatment of epilepsy and epileptic seizures (status epilepticus). Also used in some countries for the treatment of psychiatric disorders such as panic disorder.
Dosage
According to the professional information. The dose is adjusted individually. Medicines are usually administered two to three times daily.
Abdominal
Like other benzodiazepines, clonazepam can be abused as a central depressant narcotic. It can lead to dependence and cause withdrawal symptoms when discontinued.
Contraindications
- Hypersensitivity
- Respiratory failure
- Severe hepatic insufficiency
- Drug, drug and alcohol dependence
- Myasthenia gravis
For complete precautions, see the drug label.
Interactions
Clonazepam is a substrate of CYP3A4. Drug-drug interactions have been described with the following substances:
- CYP inducers
- Valproic acid
- Alcohol
- Central depressant drugs
Adverse effects
Possible adverse effects include, for example, fatigue, drowsiness, psychiatric disorders, paradoxical reactions, dependence, muscle weakness, visual disturbances, respiratory depression, and withdrawal symptoms.
