How can drugs be deactivated in the body?

The correct answer emphasizes the body's ability to deactivate drugs primarily through excretion, which can occur either in their unchanged form or after they have been chemically altered by metabolic processes. This highlights the dual pathways of drug clearance: the body can eliminate drugs directly or modify them into different compounds that are more easily excreted.

The liver plays a crucial role in biotransformation, where enzymes chemically convert drugs into metabolites, which can then be excreted more readily through urine or bile. This metabolic process not only helps in detoxifying substances but also aids in preventing the accumulation of drugs in the body, minimizing potential toxicity.

In contrast, methods like diluting drugs with water do not effectively deactivate them within the body and do not represent a physiological mechanism of drug clearance. Chemical alteration is certainly part of the process, but it is not the only means by which drugs are deactivated, as excretion also plays a significant role. Increasing the dosage over time does not facilitate deactivation; rather, it could lead to an accumulation of drug effects and potential toxicity. Therefore, the route involving excretion, whether unchanged or altered, is the most comprehensive and accurate representation of how drugs are deactivated in the body.