Adsorption distribution analgesics

Most sedative-hypnotic drugs are lipid-soluble and are absorbed well from the gastrointestinal tract, with good distribution to the brain. Drugs with the highest lipid solubility (eg, thiopental) enter the CNS rapidly and can be used as induction agents in anesthesia. The CNS effects of thiopental are terminated by rapid redistribution of the drug from brain to other highly perfused tissues, including skeletal muscle. Other drugs with a rapid onset of CNS action include eszopiclone, zaleplon, and zolpidem