Depressores

Depressores, or central nervous system depressants, encompass a broad range of substances that depress neuronal activity in the brain and spinal cord. They commonly produce sedation, reduction of anxiety, impaired coordination, slowed speech, and drowsiness. Therapeutically, depressants are used for anesthesia, sedation, seizure control, sleep disorders, and pain management, but they carry a risk of misuse and harm.

Major classes include alcohol; benzodiazepines (e.g., diazepam, lorazepam) and non-benzodiazepine sedative-hypnotics (like zolpidem); barbiturates; opioids (morphine, fentanyl, heroin); inhalants and certain anesthetics (isoflurane, sevoflurane). Most benzodiazepines, barbiturates, and many sedatives enhance the action of the GABA-A receptor, increasing inhibitory signaling. Opioids bind to mu/kappa receptors to produce analgesia and sedation. Some general anesthetics depress neuronal activity by multiple targets.

Risks include overdose and life-threatening respiratory depression, especially when combined with other depressants such as alcohol; cognitive and motor impairment; dependency and withdrawal syndromes; and organ toxicity with long-term use. Use is generally avoided in certain populations, such as those with respiratory or liver disease, or during pregnancy, unless clearly indicated and supervised.

Public health and clinical practice emphasize cautious prescription, monitoring for signs of misuse, and patient education about interactions, safety, and withdrawal management.