Erections, desire, and hormone therapy

Treatment for prostate cancer that has spread beyond the gland often includes changing a man’s hormone balance. This can be done in one or more of these ways:

• Removing a man’s testicles (called orchiectomy)
• Using drugs to keep testosterone from being made
• Using drugs that block cells from using testosterone

The choice to use drug treatment to block testosterone is a kind of hormone therapy that allows the testicles to stay in place. A simpler form of hormone treatment is to remove the testicles. If you and your doctor choose this method, you may want to see the information under “Loss of one or both testicles” in the “Special aspects of some cancer treatments” section.

The goal of hormone therapy is to starve the prostate cancer cells of testosterone. This slows the growth of the cancer. All of these treatments have many of the same kinds of sexual side effects, because they all block testosterone.

The most common problem with hormone treatment is a decrease in desire for sex (libido). This may be one reason men often have trouble getting or keeping erections or reaching orgasm.

Some men on hormone therapy say that their sexual desire is still strong, but they have problems getting erections. Or they may have problems reaching orgasm. The effects of hormones on the erection response are not well understood, and the side effects of hormone treatment are hard to predict. Some men are able to feel desire and have erections and orgasms, even with their testosterone blocked. Other men function well for a few years, then slowly lose interest in sex. The strong desire to stay sexually active may be the key.

Hormone therapy may also cause changes in how you look, such as loss of muscle mass, weight gain, or some growth in breast tissue. Doctors can pre-treat with external radiation to keep breasts from growing, and other medicines may help, too. If you are concerned about your breasts growing, let your doctor know before you start hormone therapy. A program of exercise may help you limit muscle loss, weight gain, and tiredness. Talk with your doctor about any exercise program you may have in mind, or ask to be referred to a physical therapist, who can help you decide where to start and what to do.

What are the psychological effects of hormone therapy?

Men who no longer have their testicles or who are on hormone therapy drugs often feel like “less of a man.” They fear they may start to look and act like a woman. This is a myth. Manhood does not depend on hormones but on a lifetime of being male. Hormone therapy for prostate cancer may decrease a man’s desire for sex, but it cannot change the target of his sexual desires. For example, a man who has always been attracted only to women will not find himself attracted to men because of this kind of hormone treatment.