Ketamine is primarily metabolized in the liver producing which active metabolite?

Ketamine is primarily metabolized in the liver producing which active metabolite?

• A. Liver and Extrahepatic
• B. Kidney and Liver
• C. Liver Only
• D. Brain

Answer: (A)

Ketamine is metabolized by hepatic cytochrome P450 enzymes to norketamine, an active metabolite. Importantly, not all of this metabolism happens in the liver—extrahepatic tissues, including brain, also contribute to forming norketamine. That’s why the active metabolite is produced by both liver and extrahepatic metabolism. If metabolism were confined to the liver only, you’d miss the contribution from tissues outside the liver.

Ketamine is metabolized by hepatic cytochrome P450 enzymes to norketamine, an active metabolite. Importantly, not all of this metabolism happens in the liver—extrahepatic tissues, including brain, also contribute to forming norketamine. That’s why the active metabolite is produced by both liver and extrahepatic metabolism. If metabolism were confined to the liver only, you’d miss the contribution from tissues outside the liver.