Effects of oral raloxifene on serum estradiol levels and other markers of estrogenicity.

Objective: To determine the effects of raloxifene hydrochloride, 60 mg/d, on serum levels of E(2), estrone, sex steroid-binding globulin, thyroxine-binding globulin, and follicle-stimulating hormone (FSH) in postmenopausal women.

Design: Randomized placebo-controlled study at 16 centers in the United States.

Patient(s): Ninety three women 42 to 80 years of age who were at least 2 years postmenopausal.

Intervention(s): Raloxifene (n = 47) or placebo (n = 46) for 3 months.

Main Outcome Measure(s): Levels of E(2), estrone, sex steroid-binding globulin, thyroxine-binding globulin, and FSH were measured at baseline and after 3 months of therapy.

Result(s): Raloxifene increased serum levels of sex steroid-binding globulin and thyroxine-binding globulin and decreased FSH levels compared with placebo. Levels of E(2) and estrone were unaffected.

Conclusion(s): In postmenopausal women, raloxifene (60 mg/d) did not increase serum estrogen levels; however, it increased levels of sex steroid-binding globulin and thyroxine-binding globulin and decreased FSH levels.