Which organ is primarily responsible for detoxifying drugs and metabolizing substances in the body?

The liver is the primary organ responsible for detoxifying drugs and metabolizing substances in the body. It plays a crucial role in the body's metabolism by breaking down various compounds, including medications and toxins, into forms that are easier for the body to eliminate. This process often involves enzymatic reactions that modify these substances to make them less harmful.

The liver's unique structure allows it to efficiently process blood from the digestive tract and filter out toxins before they enter the general circulation. Moreover, it produces bile, which is essential for fat digestion and also aids in the excretion of certain waste products.

While other organs, such as the kidneys and lungs, do participate in detoxification and waste elimination, they do not play as central a role in the metabolism of drugs as the liver does. The kidneys primarily filter blood to remove waste and excess substances but rely on the liver to metabolize many drugs before they are filtered for excretion. The lungs also expel volatile substances and carbon dioxide but are not responsible for drug metabolism. Thus, the liver's role in detoxifying and metabolizing substances makes it the correct answer.