Clonazepam

Clonazepam, sold under the brand name Klonopin among others, is a benzodiazepine medication used to prevent and treat anxiety disorders, seizures, bipolar mania, agitation associated with psychosis, obsessive–compulsive disorder (OCD), and akathisia.^[10] It is a long-acting^[11] tranquilizer of the benzodiazepine class.^[10] It possesses anxiolytic, anticonvulsant, sedative, hypnotic, and skeletal muscle relaxant properties. It is typically taken orally (swallowed by mouth) but is also used intravenously.^[10][12] Effects begin within one hour and last between eight and twelve hours in adults.^[8][1]

Common side effects may include sleepiness, weakness, poor coordination, difficulty concentrating, and agitation. Clonazepam may also decrease memory formation.^[10] Long-term use may result in tolerance, dependence, and life-threatening withdrawal symptoms if stopped abruptly.^[10][13] Dependence occurs in one-third of people who take benzodiazepines for longer than four weeks.^[9] The risk of suicide increases, particularly in people who are already depressed.^[10][14] Use during pregnancy may result in harm to the fetus.^[10] Clonazepam binds to GABA_A receptors, thus increasing the effect of the chief inhibitory neurotransmitter γ-aminobutyric acid (GABA).^[9]

Clonazepam was patented in 1960, marketed in 1964, and went on sale in 1975 in the United States from Roche.^[15][16] It is available as a generic medication.^[10] In 2022, it was the 57th most commonly prescribed medication in the United States, with more than 11 million prescriptions.^[17][18] In many areas of the world, it is commonly used as a recreational drug.^[19][20]