Non-occlusive compositions for transdermal delivery of 5-alpha-reductase inhibitors, and more particularly finasteride or dutasteride or pharmaceutically acceptable salts or derivatives thereof, and methods of making same. The composition may, for example, be a gel suitable for transdermal or transmucosal applications. The compositions of the present invention typically include a mixture of water and alcohol, and a solvent system having a mono alkyl ether of diethylene glycol and a glycol present in specified ratios and in specific amounts, wherein the pH of the gel is usually between about pH 4.5 and about pH 8. The compositions may include further components, for example, the hydroalcoholic vehicle may further include additional penetration enhancer(s), buffering agent(s), antioxidant(s), stabilizer(s) and/or gelling agent(s). Also, a method for the sustained delivery of 5-alpha-reductase inhibitors to treat a variety of conditions and disorders.