Which drugs may cause a decrease in serum iron levels?

The correct answer is all of the above because each of the drug combinations listed has the potential to affect serum iron levels in some manner.

Cholestyramine is a bile acid sequestrant that can bind to various substances in the intestines, including iron, potentially leading to decreased absorption and lower serum iron levels. Colchicine, used primarily for gout, can affect the intestinal mucosa and may result in reduced absorption of several nutrients, including iron.

ACTH (adrenocorticotropic hormone) can indirectly contribute to altered iron metabolism, particularly in patients with certain conditions; its administration may lead to increased cortisol levels, affecting iron transport and metabolism. Deferoxamine is a chelating agent that binds iron in the bloodstream, which can also lead to reduced serum iron levels, especially in cases of iron overload.

Methicillin, an antibiotic, is less commonly associated with direct effects on iron levels, but it can influence the gut microbiome and digestion, which might indirectly affect iron absorption. Testosterone has been shown to affect erythropoiesis and may influence iron metabolism, but its effects can vary widely among individuals.

Understanding how these drugs interact with iron metabolism is crucial in their management, especially for the elderly who may already be at