ANCC Family Nurse Practitioner Practice Exam

Cimetidine is known to potentially cause gynecomastia because it acts as a histamine H2-receptor antagonist, which can lead to an increase in estrogen levels or a change in the hormonal balance within the body. This effect may occur due to its ability to inhibit the liver enzymes involved in drug metabolism, leading to altered levels of hormones and consequently affecting breast tissue.

Gynecomastia is the enlargement of breast tissue in males, often associated with hormonal imbalances. Cimetidine's antiandrogenic effects, as well as its potential to inhibit testosterone synthesis, contribute to this condition.

In contrast, ibuprofen, acetaminophen, and aspirin do not have the same mechanism of action or effects on hormone levels that are associated with gynecomastia. They are primarily analgesics or anti-inflammatory medications and do not interfere with hormonal pathways in a way that would lead to the development of gynecomastia.