Men who use erectile dysfunction (ED) drugs recreationally may be more likely to develop psychogenic ED, the type that originates in the mind, according to new research.

"Recreational use of ED medications increased the chance of psychological dependence on ED medicines,'' says researcher Christopher Harte, PhD, a postdoctoral fellow at the VA Boston Healthcare System.

"Among young, healthy men who used ED medicines recreationally, the more frequent ED medicine use was associated with lower confidence in achieving and maintaining erections, which in turn was associated with lower erectile function," Harte says.

The study is published in the Journal of Sexual Medicine.

The researchers found a link but not cause and effect, Harte tells WebMD.

However, another expert wonders if some of the men who reported ''recreational'' use actually had ED.

ED Drugs and ED: Study Details

ED affects about 34 million men in the U.S., according to Harte.

The condition is more common with age. About 9% of men 18 to 39 are affected. Up to 70% of men 60 and older are.

However, men aged 18 to 45 are responsible for the largest increase in the use of Viagra among U.S. adults, Harte reports. From 1998 to 2002, the use by this age category grew 312%, he says.

For his study, Harte evaluated 1,207 men. Their average age was about 22.

• 72 were recreational users, reporting no diagnosis of ED from a doctor
• 1,111 were non-users of ED drugs
• 24 were prescribed the drugs and used them

The men completed an online survey. It asked about their sexual functioning in the past four weeks. They told whether they used ED drugs and how often.

They answered questions about their erectile function, orgasm, sexual desire, and their satisfaction with intercourse and overall sex.

They reported their levels of confidence in their ability to get and maintain an erection.

ED Drugs and ED: Study Results

Compared to non-users, recreational users reported lower erectile confidence and overall satisfaction.

The decreased confidence, in turn, was linked negatively with erectile functioning, he says. 

Harte can't explain the link for sure. "It very well could be that recreational ED medication users may start having unreasonable standards or expectations about their erectile performance," he says.

That, in turn, could lead to men becoming overly sensitive about their performance and more dissatisfied, he says.

ED Drugs and ED: Perspective

The young men who were in the ''recreational'' category may actually have ED, says Irwin Goldstein, MD, editor-in-chief of The Journal of Sexual Medicine and a physician at Alvarado Hospital in San Diego.

"For those people who did use it recreationally, perhaps the explanation is, they were too embarrassed to announce [to their doctor] they have a sexual health problem," he tells WebMD.

They may have bought the drugs over the Internet, he says, without seeing a doctor.

There is no way to know for sure if all the men were honest, Harte says. "However, given that it was an anonymous, online survey, where they could complete the questionnaires in private and at their own pace and discretion, likely buffers, to a degree, any concerns with validity," he says.

If a young man does see a doctor for ED concerns, Goldstein says, some doctors may have trouble believing it could affect someone who doesn't have typical risk factors, such as high blood pressure or diabetes.

"Most 18- to 20-year-olds don't have those risk factors," he says. However, he says, "there can be other reasons for blocked blood flow to the penis."

Goldstein reports consultant work for makers of ED drugs, including Pfizer and Eli Lilly and Company.

ED Drugs and ED: Industry Comments

ED drugs are not meant for recreational use by those who don't have ED, according to spokespersons for the makers of two ED drugs, Cialis and Viagra.

According to Teresa Shewman, spokeswoman for Eli Lilly and Company: "Cialis is approved for use with a prescription only and Lilly does not condone the use of ED medication for off-label or recreational purposes."

"Viagra is approved for use in men age 18 or older who have been diagnosed with erectile dysfunction (ED),'' according to Christopher Loder, spokesman for Pfizer, which makes Viagra. "It should not be used by men who have not been diagnosed with erectile dysfunction."

SOURCES: Christopher Harte, PhD, postdoctoral fellow, VA Boston Healthcare System.Harte, C. Journal of Sexual Medicine, July 2012.Christopher Loder, spokesman, Pfizer.Irwin Goldstein, editor, Journal of Sexual Medicine; sexual dysfunction researcher and physician, Alvarado Hospital, San Diego, Calif.Teresa Shewman, spokeswoman, Eli Lilly and Company.

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