Klonopin

Klonopin is the brand name for clonazepam, a prescription benzodiazepine used to treat seizure disorders and panic disorder. It belongs to the sedative-hypnotic anxiolytic class and acts by enhancing the effect of the neurotransmitter gamma-aminobutyric acid (GABA) at the GABA-A receptor, increasing chloride ion influx and producing central nervous system depression.

Medical uses: It is approved as adjunctive therapy for various seizure disorders in adults and children, and as a treatment for panic disorder in adults. It is sometimes used off-label for other anxiety disorders, insomnia, and certain movement disorders.

Pharmacokinetics: clonazepam is taken orally as tablets or disintegrating tablets. It is rapidly absorbed with onset typically within 20 to 60 minutes. It has a long half-life, commonly around 18 to 50 hours, which leads to relatively stable levels with regular dosing. It is extensively metabolized by the liver, mainly via CYP3A4, and its metabolites are excreted in urine.

Side effects and risks: Common adverse effects include drowsiness, fatigue, dizziness, impaired coordination, and cognitive slowing. Long-term use can lead to dependence and withdrawal; abrupt discontinuation can cause rebound symptoms and withdrawal syndromes. Co-administration with alcohol or other central nervous system depressants increases the risk of excessive sedation and respiratory depression. It carries risks in pregnancy and breastfeeding; exposure may harm the fetus, and neonatal withdrawal has been reported.

Contraindications and cautions: Use with caution in older adults, people with liver disease, respiratory impairment, or a history of substance use disorder. Dose should be tapered when stopping to minimize withdrawal effects.

Regulatory status: In many countries it is a prescription-only drug. In the United States it is a Schedule IV controlled substance with potential for abuse and dependence.