The present invention involves the novel use of H.sub.2 and H.sub.3 agonists, as erectogenic agents in the treatment of male and female sexual dysfunction in an animal, including humans. The H.sub.2 and H.sub.3 agonists may be administered by intracavernousm injection, topically, transdermally, or intraurethrally. The method of use may also include a second therapeutic agent which either facilitates, potentiates or is erectogenic. The second agent may be administered sequentially or contemporane...