Which hormone therapy, given for treatment of prostate cancer, may cause an initial flare?

Luteinizing hormone-releasing hormone (LHRH) analogs are a class of medications used for the treatment of prostate cancer that can induce an initial flare in testosterone levels before ultimately decreasing them. When LHRH analogs are administered, they initially stimulate the pituitary gland to release luteinizing hormone and follicle-stimulating hormone, which in turn leads to an increase in the production of testosterone by the testes. This phenomenon is known as the "flare effect."

The initial surge in testosterone can temporarily exacerbate symptoms, especially in patients who have metastatic disease. However, continued administration of LHRH analogs will suppress the secretion of luteinizing hormone and follicle-stimulating hormone, leading to a significant reduction in testosterone levels over time. This is an important consideration in the management of prostate cancer, as elevated testosterone levels can potentially stimulate tumor growth.

In contrast, estrogen therapy, androgen receptor blockers, and GnRH antagonists do not produce this initial flare effect. Estrogen therapy can lower testosterone levels but does not create an initial surge. Androgen receptor blockers directly inhibit the action of androgens and do not affect the production of testosterone. GnRH antagonists work differently by blocking GnRH receptors, leading to