Drug metabolism primarily occurs in the liver, but it can also take place in other organs to a lesser extent, such as the:

* Intestines: Some drug metabolism occurs in the intestinal wall.

* Kidneys: The kidneys metabolize some drugs as they filter waste products from the blood.

* Lungs: The lungs metabolize some volatile drugs.

* Plasma: Some drug metabolism can occur directly in the bloodstream.

However, the liver is the main site of drug metabolism due to its high concentration of enzymes responsible for this process.