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When sexually stimulated there is a release of a chemical, nitric oxide (NO) in the blood vessels of the corpus cavernosum. The NO stimulates the production of a compound called cGMP, which causes relaxation of the smooth muscle in the blood vessels supplying the corpus cavernosum. PDE 5 is an enzyme that breaks down cGMP. By inhibiting the breakdown of cGMP by PDE5, these medications allow cGMP to build up in the penis. cGMP causes muscles in the corpora cavernosa of the penis to relax. When the muscle is relaxed, more blood can flow into the penis and fill the spaces in the penis. As the penis fills with blood, the veins in the penis are compressed, and this results a hard erection. When the effect on PDE5 decreases, the cGMP levels go down and the muscle in the penis contracts, causing less blood to flow into the penis and allowing the veins to open up and drain blood out of the penis.
These are not currently approved by the FDA for ED management, but they may be offered through research studies (clinical trials). Patients who are interested should discuss the risks and benefits (informed consent) of each, as well as costs before starting any clinical trials. Most therapies not approved by the FDA are not covered by government or private insurance benefits.
These findings demonstrate the importance of recognizing a possible organic component of ED even in younger men. In fact, in younger, more than in older men, who are by definition at high CV risk, searching for signs of metabolic or CV disorders can help identify those men who apparently healthy, have subtle and subclinical conditions that can be treated before the damage becomes clinically overt.
Andrew McCullough, MD, associate professor of clinical urology and director, male sexual health program, New York University Langone Medical Center. Lecturer: Auxillium. Research grant: Pfizer. Data safety monitoring board: Pfizer. Consultant: Slate Pharmaceuticals. Clinical trials: Warner Chilcott, Vivus, Lilly, Bayer-GSK, ICOS, Timm, Schering Plough, Aeterna.
Patients taking PDE5 inhibitors should avoid consuming large amounts of alcohol, which may cause a sudden decrease in blood pressure when getting up from a standing or reclining position. Although effects can be variable, symptoms may include a fast heart rate, dizziness, headache and fainting. Studies with some PDE5 inhibitors have shown a decrease in blood pressure and symptomatic effects when combined with alcohol.
“With the success of Viagra-type drugs, there has been a tendency to start all patients with ED on one of these drugs and not look much further for a medical cause. But we now know that ED may be an early warning for heart and blood vessel disease, so it is important to look for common risk factors. These include high blood pressure, diabetes, medications, smoking, drinking, and drugs,” said Dr. Wang.
Think of erectile dysfunction as your body’s “check engine light.” The blood vessels in the penis are smaller than other parts of the body, so underlying conditions like blocked arteries, heart disease, or high blood pressure usually show up as ED before something more serious like a heart attack or stroke. ED is your body’s way of saying, “Something is wrong.” And the list of things that cause erectile dysfunction can include:

Diabetes is known to sabotage two body parts that provide essential components of an erection: nerves and blood vessels. Studies suggest that diabetic nerve damage (neuropathy) is the most important risk factor for ED in people with diabetes. If pelvic nerves that trigger penis muscles to relax are impaired, there may be a break in the chain between brain and penis, disrupting erection. Some researchers suspect that an inadequate supply of oxygen to the nerves causes this damage.

Long-term erectile dysfunction. The risk for long-term erectile dysfunction has been linked to chronic heavy use of alcohol. In fact, studies show that men who are dependent on alcohol have a 60 to 70 percent chance of suffering from sexual problems. The most common of these are erectile dysfunction, premature ejaculation, and loss of sexual desire.

This patient has thoroughly researched erectile dysfunction on the internet and has a powerful knowledge base from which he draws reference. He is also emotionally labile. The most urgent recommendation for this patient is that he seek appropriate psychiatric treatment to help in management of his psychiatric conditions and suicidal ideation. It was also recommended that he seek care with a sexual therapist to work through additional issues related to his “addiction” to masturbation. During his urologic visit we performed both cold and hot perception testing and biothesiometer, which were normal. He was displeased with these findings as they were incongruent with his chief complaints; normal results caused him to become tearful. A penile ultrasound was performed without injection of a pharmacologic agent to assess the appearance of his cavernous tissue and cavernous arteries, which had normal appearance and measurement, respectively, on ultrasound. (This quick bedside procedure has the potential to be both diagnostic and therapeutic for the patient; the importance of this cannot be underestimated).

I think that a very powerful argument to young men who want to perform at the highest level is to point out the destructive nature of what they’re doing. If they’re having 18 drinks per week, if they’re having three, four, five drinks at any one time, they’re going to guarantee that their erections are not going to be at the highest level. I can’t tell you the number of men who come in saying, they went out, they had a date, they had a big dinner– which, by the way, is also not a great thing for erections, because all the blood is now going to your gut instead of to the genital area. And how important lifestyle changes are to improving your performance, as well, if not better, than the medications. So make certain that you exercise modestly, not excessively. Make certain that you have a smaller meal on an evening or a day that you want to have a sexual encounter, because you want the blood to go, once again, to the penile area and not to your gut. And really, the whole idea of stress– if you’re stressed out, if you’re worried about a lot of things, if you’re distracted, you can’t initiate that psychic stimulus to your spinal cord and then ultimately to your penis. So stress management is incredibly important.
Having learned a great deal more about erectile dysfunction including its risk factors and causes, you should be equipped to assess your own erectile function. If you have experienced erectile issues or you have some of the risk factors mentioned above, it may be worth making a trip to your doctor’s office. If you choose to seek help, give your doctor as much information as you can about your symptoms including their frequency and severity as well as the onset. With your doctor’s help, you can determine the best course of treatment to restore sexual function.
The symptoms of erectile dysfunction include difficulty achieving an erection, trouble maintaining an erection, and a reduced interest in sex. Because male sexual arousal is a fairly complex process, it can sometimes be difficult to identify a specific cause. Arousal starts in the brain but it also involves the nerves, muscles, and blood vessels and can be impacted by hormones and emotions. If a problem develops with any of these things, erectile dysfunction could be the consequence.
Erections are neurovascular events, meaning that nerves and blood vessels (arteries and veins) are involved in the process of an erection and all must work properly to develop a hard erection that lasts long enough. Erection begins with sexual stimulation. Sexual stimulation can be tactile (for example, by a partner touching the penis or by masturbation) or mental (for example, by having sexual fantasies, viewing porn). Sexual stimulation or sexual arousal causes the nerves going to the penis to release a chemical, nitric oxide. Nitric oxide increases the production of another chemical, cyclic GMP (cGMP), in the muscle of the corpora cavernosa. The cGMP causes the muscles of the corpora cavernosa to relax, and this allows more blood to flow into the penis. The incoming blood fills the corpora cavernosa, making the penis expand.
The relationship between ED and couple relation impairment is well documented. In our population of subjects consulting for sexual dysfunction, subjects reporting conflicts within the couple were characterized by a broad spectrum of sexual symptoms, including a severe extent of ED, and they had a higher SIEDY Scale 2 score, indicating a strong relational component in the pathogenesis of ED (88). If on one hand, it is easy to understand that problems in couple relationship can cause ED, the other way around is also feasible. In the Female Experience of Men’s Attitudes to Life Events and Sexuality (FEMALES) study, 292 female partners of men aged more than 20 years complaining for ED were involved in a survey assessing the quality of their sexual experience (89). In this study, women reported a significant deterioration of satisfaction for sexual intercourse after the onset of ED in their partners. The satisfaction, sexual desire, arousal and orgasm were then improved in women whose partner used PDE5i (89). The role of ED as a risk factor for female dysfunction, including impairment in arousal, orgasm, sexual satisfaction and sexual pain, has been also confirmed in a study involving 632 sexually active couples, whose male partner age ranged 18–80 years (90).
Dr. Jonas Bovijn is the co-first author of the study and is from the Big Data Institute at the University of Oxford. He said: “We know that there is observational evidence linking erectile dysfunction and type 2 diabetes, but until now there has not been definitive evidence to show that predisposition to type 2 diabetes causes erectile dysfunction.”
Does drinking water improve erectile dysfunction? Erectile dysfunction or ED is a common concern for men. Everyday factors, such as hydration levels, may affect a person's ability to get or maintain an erection. Drinking water may, therefore, help some men with ED. In this article, learn about the link between hydration and ED, and other factors that can cause ED. Read now
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