Partitioning into the brain

Intravenous anesthetics are also relatively lipid-soluble, which helps account for their rapid onset. This high degree of lipid solubility allows them to rapidly cross the blood-brain barrier and partition into the brain. Barbiturates such as thiopental and methohexitol and the nonbarbiturates etomidate and propofol are often used to induce anesthesia, but only propofol is commonly used today as a general anesthetic by continuous infusion, thus only propofol will be discussed. 

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