Medicine & USMLE


  1. Ketamine
  2. Nitrous Oxide (N2O)
  3. Local Anesthetics
  4. Nondepolarizing Neuromuscular-blocking Drugs
  5. Succinylcholine
  6. Halothane and Fluranes
  7. Propofol
  8. Thiopental


Propofol is an IV anesthetic with strong sedative properties. It is thought to function via potentiation of GABA signaling in the brain, decreasing membrane excitability and ultimately inhibiting neuronal activity. Clinically, propofol is a useful agent for reducing pain and inducing sedation, used primarily in the setting of anesthesia. One of the most important side effects of propofol is profound hypotension due to a combination of reduced systemic vascular resistance and depression of myocardial activity.

Key Points

  • Propofol
    • Mechanism
      • Not well understood; thought to be GABA agonist
        • GABA is an inhibitory neurotransmitter; increased GABA signaling causes CNS depression and reduced neuronal signaling
    • Clinical Use
      • Induction of Anesthesia
        • IV propofol is used to induce and maintain anesthesia for a variety of procedures
    • Adverse Effects
      • Hypotension
        • Thought to reduce sympathetic outflow and alpha-1 activity to cause vasodilation, reducing vascular resistance
        • Also depresses myocardial contractility, which reduces cardiac output