Not so long ago, erectile dysfunction (ED) was a problem that men seemed to accept as a natural, if frustrating, consequence of aging. Then in the spring of 1998, Viagra—the first oral medication to treat ED—hit the market, followed a few years later by Levitra and Cialis. Another ED drug, Stendra, was approved in 2012. The phenomenal response to these pharmaceutical solutions for ED has been dubbed a second sexual revolution, the first having occurred with the advent of birth control pills. Both types of medications fostered major changes in sexual behavior and the ways in which people think about and talk about sexuality.

What is erectile dysfunction?

Simply put, ED is trouble attaining and sustaining an erection sufficient for sexual intercourse. At least 25% of the time, the penis doesn’t get firm enough, or it gets firm but softens too soon.

Often, the problem develops gradually. One night it may take longer or require more stimulation to get an erection. Another time, an erection may not be as firm as usual, or it may end before orgasm. When such difficulties occur regularly, it’s time to talk to your doctor.

Causes of erectile dysfunction

Failing to have an erection one night after you’ve had several drinks—or even for a week or more during a time of intense emotional stress—is not ED. Nor is the inability to have another erection soon after an orgasm. Nearly every man occasionally has trouble getting an erection, and most partners understand that.

Often, the culprit behind ED is clogged arteries (atherosclerosis), which can affect not only the heart but also other parts of the body. In fact, in up to 30% of men who see their doctors about ED, the condition is the first hint that they have cardiovascular disease. Other possible causes of ED include medications and prostate surgery, as well as illnesses and accidents. Stress, relationship problems, or depression can also lead to ED.