Diazepam belongs to which drug class?

• A. Opioid
• B. Benzodiazepine
• C. Barbiturate
• D. Anticholinergic

Answer: (B)

Diazepam is a benzodiazepine. This class binds to a specific site on the GABA-A receptor and acts as a positive allosteric modulator, increasing the effect of GABA. When GABA activates the receptor, the chloride channel opens more frequently, boosting inhibitory signals in the brain and producing sedation, anxiolysis, anticonvulsant effects, and muscle relaxation. Diazepam has a relatively long half-life with active metabolites, so its effects can last longer and it’s useful for prolonged anxiety control, seizure management, and alcohol withdrawal. This mechanism distinguishes it from other drug classes: opioids act on mu receptors for analgesia and do not modulate GABA-A; barbiturates also affect GABA-A but by increasing the duration of chloride channel opening and carry higher risks of respiratory depression; anticholinergic drugs block acetylcholine receptors and don’t provide the same GABAergic CNS depressant effects.