Depressants categorized into barbiturates, non-barbiturates, alcohol: barbiturates. Helps people sleep/relax but doesn"t allow for rem sleep. Work through gava(primary inhibitory amino acid neurotransmitter in brain), increase of gava=slow things down, barbiturates bind to gava receptors. Also synergistic with other sedatives (additive if you put them together, not independent) Biggest group they"re used for are elderly. Withdrawal: potential for seizures depending on how much you"ve taken them, can administer other depressants in place to reduce withdrawal (alcohol: alcohol. Cns depressant, produced by yeast digesting sugar and excreting alcohol. Most damaging to society largest admissions to mental hospitals (40%), 55% of all arrests, 50- 75% yo all homicides, 50% of death by car accidents, 20% suicides. Instead of trying to take it away, educate people about it. Effects gava receptor or slowing metabolic activity/altering membrane excitability, don"t know for sure how it works.