When barbiturates (a type of depressant drug which causes relaxation and sleepiness) are taken in relatively low doses, the clinical syndrome of intoxication is indistinguishable from that associated with alcohol intoxication.

However, excessive and prolonged dosages of barbiturate drugs, such as phenobarbital, may produce chronic symptoms including forgetfulness (memory loss), irritability, changes in alertness, and decreased interpersonal functioning. Barbiturates can also cause an acute overdose syndrome which is life-threatening.

Barbiturate abuse is still a major addiction problem, though it has been partly replaced by other addiction to other depressant drugs which are now more commonly prescribed instead of barbiturates, such as benzodiazepines.

Though most people who take these medications for seizure disorders or pain syndromes do not abuse them, many current abusers started abusing medication prescribed for them or for other family members.