Nafoxidine hydrochloride is primarily used in research settings to study its effects on estrogen receptors. It acts as a selective estrogen receptor modulator (SERM), making it valuable for investigating hormone-dependent conditions, such as breast cancer. Its ability to block estrogen activity helps researchers understand tumor growth mechanisms and develop targeted therapies. Additionally, it has been explored in studies related to reproductive health and endocrine system regulation. While not widely used in clinical practice, its role in experimental pharmacology remains significant for advancing knowledge in hormone-related diseases.