How do some intravenous anesthetics affect inhibitory nerve signals in the brain?

Intravenous anesthetics produce their effects by acting on the central nervous system to block signal transmission across synapses. While the exact mechanisms of these agents are not entirely understood, evidence indicates that some intravenous anesthetics function primarily by stimulating the activity of inhibitory neuronal transmission in the brain.1

This action contrasts with many inhalation anesthetics, which are thought to block synapses involved in excitatory neuronal transmission. By enhancing inhibitory signals, these intravenous agents—such as barbiturates, benzodiazepines, propofol, and etomidate—effectively suppress responses to sensory stimulation, leading to a rapid and controlled state of anesthesia.12