Barbiturates produce all degrees of depression of the CNS, ranging from mild depression to general anesthesia. Barbiturates are available as sedative hypnotic or for use in combination with analgesic, antihypertensive, anti-asthmatic, antispasmodic, or antidiuretic drugs. Amobarbital, Secobarbital, Butalbital ; Pentobarbital are the most abused barbiturates because of their rapid onset and short duration of action. Detection period in urine following ingestion of barbiturates depends on pharmacological properties of the drugs. Short to intermediate acting can be detected for 1-4 days following use, while long acting barbiturates can be detected for several weeks after long term use.