depressant de·pres·sant (dĭ-prěs'ənt)
Tending to lower the rate of vital physiological activities. n.
An agent, especially a drug, that decreases the rate of vital physiological activities.
in medicine, a drug or other agent that slows the activity of vital organs of the body. Depressants acting on the central nervous system include general anesthetics, opiates, alcohol, and hypnotics. Tranquilizing drugs (ataractics) act primarily on the lower levels of the brain, relieving tension without reducing mental sharpness.
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