Sexual dysfunction refers to a problem occurring during any phase of the sexual response cycle that prevents the individual or couple from experiencing satisfaction from the sexual activity. The sexual response cycle traditionally includes excitement, plateau, orgasm, and resolution. Desire and arousal are both part of the excitement phase of the sexual response. Many physical and/or medical conditions can cause problems with sexual function. These conditions include diabetes, heart and vascular (blood vessel) disease, neurological disorders, hormonal imbalances, chronic diseases such as kidney or liver failure, and alcoholism and drug abuse. In addition, the side effects of some medications, including some antidepressant drugs, can affect sexual function. Sexual dysfunction occurs when you have a problem that prevents you from wanting or enjoying sexual activity. It can happen anytime. Men and women of all ages experience sexual dysfunction, although the chances increase as you age.