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You can't buy good health but you can buy good health information. Check out these newly released Special Health Reports from Harvard Medical School:

What to do about Erectile Dysfunction

If you’ve experienced ED, you know you are not alone. Just flipping on the TV will tell you that. Ads for Viagra, Levitra, and Cialis abound.

More than 30 million American men are affected by ED. ED can be disheartening. It can stress relationships, sap self-esteem, and steal some of the joy from life. The good news is the odds of finding a solution that works for you are greater than ever.

What to do about Erectile Dysfunction, prepared by the doctors of Harvard Medical School offers, a straightforward discussion of the causes of erectile dysfunction, why it is widespread, and what you can do to ease, control, and turn back its effects.

Did you know, for example, that men who exercise 30 minutes a day are 40% less likely to have ED than sedentary men? Or that ED is twice as prevalent among men with depression? Or that men with high HDL cholesterol are far less likely to have ED than men with low HDL cholesterol? The report gives you six all-natural sex tips — lifestyle changes that can help you sidestep or reverse ED.

And if you are experiencing ED, seeing your doctor is much more important than you might think. Because vascular disease is the leading cause of erectile dysfunction, ED may be an early warning sign of a more serious problem like heart disease or high blood pressure. The report examines the major culprits including atherosclerosis, nerve damage, diabetes, prostate cancer, BPH, medications, and psychological factors.

Before another night goes by, make this the day you act!  Order your copy of What to do about Erectile Dysfunction today.

Prepared by the editors of the Harvard Health Publications in consultation with Michael Philip O'Leary, M.D., Senior Surgeon at Brigham and Women's Hospital and Professor of Surgery at Harvard Medical School. 42 pages. (2014)

  • Understanding ED
    • What is ED?
    • How common is ED?
  • How an erection occurs
  • Causes of ED
    • Vascular disease
    • Nerve problems
    • Metabolic syndrome
    • Diabetes
    • Prostate cancer
    • Benign prostatic hyperplasia
    • Medications
    • Hormonal disorders
    • Psychological factors
    • Overweight and inactivity
    • Smoking
    • Alcohol and substance abuse
    • Other culprits
  • Diagnosing ED
    • Providing your medical history
    • The physical exam
    • Tests
  • A questionnaire to evaluate ED
  • Treating ED
    • Including your partner
    • Counseling
    • Drug therapy: Viagra and beyond
    • Injections
    • MUSE therapy
    • Yohimbine (Yocon)
    • Hormone therapy
    • On the horizon: Potential new drugs and other treatments
    • Devices to help achieve or maintain an erection
    • Vascular surgery
    • Surgical implants
  • Special bonus section: Creating a better sex life
  • Resources
  • Glossary

Drug therapy: Viagra and beyond

Sildenafil (Viagra) revolutionized the way we think about—and treat—ED, largely because it is effective and easy to use. Since 1998, when Viagra was first approved, the FDA has approved a number of similar drugs—namely, vardenafil (Levitra, Staxyn), tadalafil (Cialis), and avanafil (Stendra). And it has also approved a low-dose version of Cialis for daily use, creating an option that—theoretically, at least—makes having sex a possibility without advance planning.

Each of these drugs, known medically as PDE5 inhibitors, works in a similar fashion, by affecting the normal physiology of the penis. In particular, they block PDE5, an enzyme that breaks down the erection-producing chemical cyclic guanosine monophosphate. This enables the penis to fill with blood and to stay erect long enough for intercourse. Of course, it’s important to realize that none of these drugs is an aphrodisiac. You must feel sexually aroused in order for them to work.

The main difference among the drugs has to do with timing—specifically, how quickly they begin to work, and how long their effects last. The biggest divide lies between Cialis for daily use, which keeps a steady supply of the drug in the bloodstream, and the as-needed dosing offered by the other drugs, including the original form of Cialis. Among the nondaily pills, Levitra may start working faster than Viagra (within a half-hour instead of an hour)—and Staxyn, which dissolves under the tongue, may work marginally faster than Levitra—although the FDA says that like Viagra, these drugs should be taken about an hour before sexual activity. Some studies suggest that Levitra may help some men who don’t respond to Viagra. And while some doctors are skeptical about this claim, there’s no harm in trying one of the other PDE5 inhibitors if Viagra doesn’t work for you.

Cialis stays active in the body much longer than the other drugs. Viagra and Levitra last about four to five hours (and sometimes up to 12 hours), while Stendra lasts about six. But with Cialis, the window of opportunity ranges from 24 to 36 hours, which is why it’s sometimes called “the weekend drug.” (By contrast, the low-dose daily option aims to allow a man to be prepared for sex anytime) Another difference among the three drugs is that while Viagra’s action may be delayed or impaired when taken with food (especially high-fat foods), that’s not the case with any of the other PDE5 inhibitors.

Success rates

Because Viagra has been available the longest, there’s more research available on this drug. Pooled data involving studies of 6,659 men have shown that Viagra helped 83% of men have intercourse at least once. On the other hand, Viagra is not a panacea. A study of its long-term effectiveness, published in The Journal of Urology, reported a somewhat lower overall success rate (69%). The success rates for Levitra and 36-hour Cialis are similar to those for Viagra (59% and 69%, respectively).

Not as much information is available on the effectiveness of the daily Cialis pill. One small study found that effectiveness varies depending on dose—2.5 milligrams (mg) or 5 mg—and level of ED:

  • severe ED: 27% (2.5 mg) to 33% (5 mg)
  • moderate ED: 56% (2.5 mg) to 61% (5 mg)
  • mild ED: 73% (2.5 mg) to 82% (5 mg).

It’s worth noting that effectiveness of placebo was 57% for mild ED, 27% for moderate ED, and 9% for severe ED.

Viagra has proved beneficial for many men with ED resulting from spinal cord injuries. In one study, 83% of such men who took Viagra had improved erections. But for men with diabetes or advanced heart disease, the drug helped only about half of the time. The response was even lower—about 30%—for men who had undergone radical prostatectomy.

The following reviews have been left for this report. Log in and leave a review of your own.

I found the publication useful and informative. I have been researching this for some time so there wasn't a lot of new information but very confirming of what I knew. I specifically appreciated the percentages attached to treatment under varying conditions.
This topic is not one to search for on the internet because of spam/junk mail danger! The Harvard publication helps greatly in making sense of the condition. The well-written, in-depth material answers questions and gives up-to-date, reliable information.
Excellent information....easy to understand.
This is a well written article focusing predominantly on medical causes and treatments. There is also attention paid to the relational and psychological components with a good resource section in the back. There is also a questionnaire to evaluate ED that is very good. Review by: Neil Cannon, Ph.D. Sex Therapist & Couples Counselor Denver, Colorado HBS, OPM, Class of 1987

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