Androgenetic alopecia, alopecia areata, and telogen effluvium are the primary nonscarring alopecias found in clinical practice. Androgenetic alopecia is considered to be the most common form of human alopecia and is postulated to affect more than 50% of men by age 50. Alopecia areata affects up to 2% of the U.S. population. Telogen effluvium frequently occurs after major life events, such as a severe illness, childbirth, or high fever, and may be associated with the use of certain medications or iron deficiency, particularly in women. The focus of this review is on the medical treatment of these common hair loss conditions.