Clonazepam, sold under the brand Klonopin among others, is a medication used to prevent and treat seizures, panic disorder, anxiety, and the movement disorder known as akathisia. It is a tranquilizer of the benzodiazepine class.
Common side effects include sleepiness, poor coordination, and agitation. Long-term use may result in tolerance, dependence, and withdrawal symptoms if stopped abruptly. Dependence occurs in one-third of people who take clonazepam for longer than four weeks. There is an increased risk of suicide, particularly in people who are already depressed. If used during pregnancy it may result in harm to the fetus. Clonazepam binds to GABAA receptors, thus increasing the effect of the chief inhibitory neurotransmitter γ-aminobutyric acid (GABA).