<p>Thiopental, a barbiturate, is used for the induction of anesthesia prior to the use of other general anesthetic agents and for induction of anesthesia for short surgical, diagnostic, or therapeutic procedures associated with minimal painful stimuli. Thiopental is an ultrashort-acting depressant of the central nervous system which induces hypnosis and anesthesia, but not analgesia. It produces hypnosis within 30 to 40 seconds of intravenous injection. Recovery after a small dose is rapid, with some somnolence and retrograde amnesia. Repeated intravenous doses lead to prolonged anesthesia because fatty tissues act as a reservoir; they accumulate Pentothal in concentrations 6 to 12 times greater than the plasma concentration, and then release the drug slowly to cause prolonged anesthesia<br />
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Thiopental binds at a distinct binding site associated with a Cl-&nbsp;ionopore at the GABAA&nbsp;receptor, increasing the duration of time for which the Cl-&nbsp;ionopore is open. The post-synaptic inhibitory effect of GABA in the thalamus is, therefore, prolonged.</p>