Topical compositions for use in the control of sexually transmitted diseases (for example HIV/AIDS) are provided. The compositions include zinc compounds, for example zinc oxide. The zinc compounds are non water-soluble or sparingly water soluble and may be present in amounts between 25% and 50% by weight of the compositions. In selected embodiments of the invention, from 1% to 60% inclusive by weight of the compositions comprises zinc compounds having a particle size not exceeding 100 nanometers. The compositions further include pharmaceutically acceptable carriers within which the zinc compounds are dispersed. A method of manufacturing a topical composition for prophylaxis against sexually transmitted diseases is also provided, the method including heating a carrier to a liquid form and mixing with it a zinc compound as described above. Also described are mechanical contraceptive devices, for example condoms, coated with topical compositions according to the invention.
