Oral finasteride, a type II 5 alpha-reductase inhibitor, has been shown to increase hair growth and slow progression of thinning in men with androgenetic or male pattern balding (Hamiliton type) but has no affect on hair growth in postmenopausal women with female pattern hair loss (Ludwig type). We describe 4 cases of hair loss with characteristics of both male and female patterns in women with hyperandrogenism in which finasteride has improved or stabilized the alopecia. Improved hair growth was seen after 6 months, 1 year, 2 years, and 2.5 years, respectively. The finding that finasteride treatment improves pattern hair loss in women with hyperandrogenism but does not affect those postmenopausal women with female pattern hair loss without hyperandrogenism supports the concept that not all types of female hair loss have the same pathophysiology.