Which of the following factors can prolong the half-life of a drug in the body?

The half-life of a drug refers to the time it takes for the concentration of the drug in the bloodstream to reduce to half of its original value. Various physiological factors can influence this process.

An increased proportion of adipose tissue can prolong the half-life of a drug primarily due to the fact that many drugs are lipophilic (fat-soluble) and can be stored in fat tissues. When a person has a higher amount of body fat, the drug may be absorbed and distributed into the adipose tissues more extensively, leading to a slower release back into the bloodstream. This slower release can extend the duration that the drug remains active in the body, thereby prolonging its half-life.

The other factors mentioned may influence drug metabolism and clearance in other ways, but they do not contribute to prolonging the half-life effectively in the same manner as increased adipose tissue does. For instance, increased thyroid function typically enhances metabolism and can lead to faster drug clearance, while chronic dehydration might concentrate the drug in the body but not necessarily lengthen its half-life. Chronic elevation of blood pressure does not have a direct impact on drug metabolism or half-life in a meaningful way compared to the effects of increased adipose tissue.