Phenobarbital is a long - acting barbiturate causing generalized depression of neuronal activity in the brain. Its effect in primarily achieved through enhanced GAB-mediated synaptic inhibition. Its use as an antiepileptic agent was first described in 1912. Before the introduction of phenytoin, Phenobarbital is used as sedative-hypnotics. It is used for the treatment of epilepsy and status epilepticus. All barbiturates including Phenobarbital, have a high potential for abuse, They were frequently used for suicide attempts in the pats, but they have in large part been replaced by benzodiazepines. The onset of symptoms depends on the drug and the route of administration, Mild to moderate barbiturate intoxication resembles ethanol inebriation with slurred speech, ataxia, and lethargy. Severe acute barbiturate intoxication is life threatening Early deaths are generally cardiovascular-related. Hypotension, shock. Pulmonary edema. And cardiac arrest that occurs with large doses are caused by depression on central sympathetic tone and as well as by direct depression of cardiac contractility. The potentially fatal oral dose of Phenobarbital is 6-10g. We descried an 23-year-old woman with pulmonary edema and cardiac arrest after ingestion of 18grams of Phenobarbital. She was completely recovered by successful cardiopulmonary resuscitation and hemoperfusion, We report a case with literature review.