Overview– Ketamine is a phencyclidine derivative that induces dissociative anesthesia.
– It affects EEG by dissociating thalamocortical and limbic systems.
– Hypertonus and muscle movements may occur independently of surgical stimulation.
– Ketamine induces amnesia and intense analgesia.
– Emergence delirium limits its clinical use.
Structure Activity Relationship– Ketamine has two optical isomers: S(+) and R(-). S(+) is clinically available.
– S(+) ketamine is preferred for its benefits.
– Ketamine can be dissolved in water and contains benzethonium chloride as a preservative.
Mechanism of Action– NMDA receptor antagonism and reduction in glutamate release.
– Interaction with μ, δ, κ, and κ opioid receptors.
– Effects on monoaminergic receptors and muscarinic receptors.
– Interaction with voltage-gated sodium channels.
– Interaction with nicotinic acetylcholine receptors.
Pharmacokinetics– Rapid peak plasma levels after IV and IM administration.
Metabolism– Metabolized to norketamine by cytochrome P450 enzymes.
Clinical Uses– Rapid induction of anesthesia and intense analgesia.
– Used in anesthesia, burn dressing changes, and skin grafting.
– Treatment for opioid tolerance recovery.
Adverse Effects– Cardiovascular stimulation, emergence delirium.
– Effects on cerebral blood flow, bronchospasm treatment.
– Minimal risk of allergic reactions and histamine release.
Drug Interactions– Interference with inhaled anesthetics and neuromuscular blockers.

Leave a Comment