Young men who take erectile dysfunction drugs for fun may damage their sex lives, a new study suggests.

Nearly 6 percent of the sexually active college men involved in the study reported taking drugs for erectile dysfunction(ED) without a prescription. Yet an analysis of these students' sex lives unveiled a paradox: The more ED drugs men took, the worse they felt.

“Using ED drugs recreationally has the potential to negatively influence one's confidence,” said Christopher Harte, lead author of the study published this month in the Journal of Sexual Medicine.

Men who abused ED drugs reported the same level of physical sexual functioning as non-users did, but Harte found that they were less confident about their abilities to get and maintain an erection. The recreational users also were less satisfied with their sex lives overall, even if they were satisfied during intercourse.

“One needs to be careful when they are frequently using these medications. It can set you up to have unreasonable expectations” about your sex life, said Harte, a research fellow at VA Boston Healthcare System.

Because the survey captured students' feelings at one moment in time, Harte said it isn't clear how the link worked: It could be that experimentation with ED drugs led to anxiety, or that it was underlying anxiety that had led the men to try ED drugs.

The erection-mind connection

Harte's study involved 1,200 college-age men from across the U.S. The men who took the drugs without a prescription were likely trying to achieve firmer and longer-lasting erections, according to the study.

Cleveland Clinic urologist Dr. Drogo Montague said Harte's findings confirm what many sexual health experts suspect about misuse of ED drugs.

“We understand how they work, and I don't think there's any lasting physical harm for a young man who doesn't need them, or for an older man who does,” Montague said. “But it does sometimes create these psychological problems  – and they stick around.”

Montague said it is common for a man to monitor his erection after taking an ED drug, and this “spectatoring” can detract from his pleasure. It also can turn up the activity of the sympathetic nervous system, which is responsible for people's flight-or-fight response. Normally the body turns down the activity of the sympathetic nervous system during sex.

Feeding a dependence

Urologists say there is no evidence the body develops a tolerance to ED medications. But recreational use of ED drugs may mask a natural decline in erectile function, leaving men surprised when they fail to achieve an erection, said Dr. Tobias Köhler, a spokesman for the American Urological Association.

“On average, the drugs only work for five years,” Köhler said. Meanwhile, an underlying physical problem causing ED—  high cholesterol, high blood pressure, diabetes or another issue – can continue to go untreated.

And doctors say it can take just a few troubled nights to feed a reliance on ED drugs.

“Anytime a man has a problem with his erection, he's always worried: ‘Am I going to have a problem with the next erection?'” said Dr. Jacob Rajfer, professor of urology at the David Geffen School of Medicine at UCLA. “Is that a physiological or a psychological dependence? Well, I don't know the answer to that.”

Pass it on: Men who take ED drugs without a prescription report having worse sex lives.

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