Current status of dosage forms and clinical use of conjugated estrogens

Conjugated estrogens (CE) are widely used in menopausal hormone therapy (MHT) for the relief of menopause-related symptoms (e.g., vasodilatory symptoms, neuropsychiatric symptoms, genitourinary atrophy symptoms, etc.) and the prevention of postmenopausal osteoporosis. This article reviews the characteristics, pharmacological effects, and practical applications of different dosage forms of CE (tablets, creams, and injections) in clinical practice. It has been shown that tablet CE effectively regulates the body's temperature center through systemic treatment, reduces hot flashes and night sweats, promotes bone formation, and increases bone density. Cream CE is used for local treatment to improve the genitourinary syndrome of menopause (GSM). Injectable CE is used for the treatment of abnormal uterine bleeding caused by hormonal imbalance without organ pathology. CE administered intravenously is indicated only for short-term use to rapidly and temporarily increase estrogen levels. Additionally, CE plays an important role in metabolism by improving insulin clearance and sensitivity and potentially protecting the nervous and cardiovascular systems, demonstrating a wide range of therapeutic potential. This paper provides new ideas for the design and development of drug dosage forms by exploring the formulation and application of CE.