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Erection Problems
As a man ages, the speed of his sexual responses slows, his drive to reach orgasm is delayed, and the force of his ejaculations gradually decreases. These physical changes need not be seen as problems. In many cases, they can prolong sexual enjoyment prior to orgasm.
Although occasional erection problems are common, healthy men of all ages are able to have erections.

A man has erectile dysfunction when he has persistent difficulty achieving or maintaining an erection that is sufficient to have satisfactory sexual intercourse.
Most erection problems are caused by a combination of physical and psychological factors. Physical causes of erection problems include illness, injuries, or complications of surgery (such as prostate surgery) that interfere with nerve impulses or blood flow to the penis. The use of certain medications, tobacco, alcohol, or illegal drugs may also lead to erectile dysfunction.