Benzodiazepines

Benzodiazepines (BZDs) are a class of psychoactive drugs with anxiolytic, sedative, muscle relaxant, anticonvulsant, and hypnotic properties. They act by enhancing the effect of gamma-aminobutyric acid (GABA), the main inhibitory neurotransmitter in the central nervous system.

• Drug class: Central nervous system depressants
• ATC code: N05BA (anxiolytics), N05CD (hypnotics), N03AE (antiepileptics)
• Schedule: Controlled substances in most countries (e.g., Schedule IV in the U.S.)

• Bind to the benzodiazepine site on the GABA-A receptor
• Increase the frequency of chloride channel opening → hyperpolarization of the neuron → reduced excitability

• Anxiety disorders (e.g., generalized anxiety disorder, panic disorder)
• Insomnia (short-term use)
• Seizure control (e.g., status epilepticus)
• Muscle spasms
• Alcohol withdrawal
• Procedural sedation
• Adjunctive treatment in tinnitus-related distress (off-label)

• Short-acting: Midazolam, Triazolam
• Intermediate-acting: Lorazepam, Alprazolam, Oxazepam
• Long-acting: Diazepam, Clonazepam, Chlordiazepoxide

• Common: Drowsiness, dizziness, confusion, impaired coordination
• Cognitive: Anterograde amnesia, slowed psychomotor performance
• Dependence and withdrawal with long-term use
• Risk of falls and delirium in the elderly
• Respiratory depression in overdose or when combined with other CNS depressants

• History of substance use disorder
• Severe hepatic impairment
• Sleep apnea
• Myasthenia gravis
• Use with opioids (risk of fatal respiratory depression)

• Monitor sedation level, respiratory status (especially if IV)
• Reassess regularly for continued need
• Taper gradually to avoid withdrawal

• Risk of tolerance and dependence increases with duration
• Should be avoided in elderly (Beers Criteria) unless clearly indicated
• Use lowest effective dose for the shortest duration possible

• Flumazenil (competitive antagonist of the BZD receptor) — used in overdose or procedural reversal; risk of seizures

• BZD, benzos
• Not to be confused with barbiturates (different receptor modulation)

• Antidepressants
• GABA-A receptor
• Dependence and withdrawal