Acetylcholine released by the parasympathetic nerves is thought to act primarily on endothelial cells to release a second nonadrenergic-noncholinergic carrier of the signal that relaxes the trabecular smooth muscle. Nitric oxide released by the endothelial cells, and possibly also of neural origin, is currently thought to be the leading of several candidates as this nonadrenergic-noncholinergic transmitter; but this has not yet been conclusively demonstrated to the exclusion of other potentially important substances (e.g., vasoactive intestinal polypeptide). The relaxing effect of nitric oxide on the trabecular smooth muscle may be mediated through its stimulation of guanylate cyclase and the production of cyclic guanosine monophosphate (cGMP), which would then function as a second messenger in this system.
Occasional successful sexual function and early morning erections do not preclude the possibility of endocrine dysfunction. Since abnormally low levels of testosterone frequently are the primary cause of impotence, it is recommended that determination of the blood level of testosterone be an integral part of the total evaluation of the impotent patient.
When you become aroused, your brain sends chemical messages to the blood vessels in the penis, causing them to dilate or open, allowing blood to flow into the penis. As the pressure builds, the blood becomes trapped in the corpora cavernosa, keeping the penis erect. If blood flow to the penis is insufficient or if it fails to stay inside the penis, it can lead to erectile dysfunction.
Among their findings, the panel concluded that (1) the term "erectile dysfunction" should replace the term "impotence"; (2) the likelihood of erectile dysfunction increases with age but is not an inevitable consequence of aging; (3) embarrassment of patients and reluctance of both patients and health care providers to discuss sexual matters candidly contribute to underdiagnosis of erectile dysfunction; (4) many cases of erectile dysfunction can be successfully managed with appropriately selected therapy; (5) the diagnosis and treatment of erectile dysfunction must be specific and responsive to the individual patient's needs and that compliance as well as the desires and expectations of both the patient and partner are important considerations in selecting appropriate therapy; (6) education of health care providers and the public on aspects of human sexuality, sexual dysfunction, and the availability of successful treatments is essential; and (7) erectile dysfunction is an important public health problem deserving of increased support for basic science investigation and applied research.
In some cases, ED can be a warning sign of more serious disease. One study suggests ED is a strong predictor of heart attack, stroke, and death from cardiovascular disease. The researchers say all men diagnosed with ED should be evaluated for cardiovascular disease. This does not mean every man with ED will develop heart disease, or that every man with heart disease has ED, but patients should be aware of the link.
The common PDE5 inhibitor drugs approved in the United States are sildenafil (Viagra), vardenafil (Levitra and Staxyn, the generic form), tadalafil (Cialis), or avanafil (Stendra). All of the currently approved PDE5 inhibitors work in the same way. They differ in the number of available doses, how quickly they work and last in your system, the dosing, and to some extent in the side effects. However, they generally share the same indications and contraindications. Currently, tadalafil is the only medication that patients can take on a daily basis and is approved for the treatment of both ED and BPH (benign enlargement of the prostate).
Davis Liu, MD is a board certified family physician, patient advocate, physician leader, blogger, and the author of two books, including The Thrifty Patient – Vital Insider Tips for Saving Money and Staying Healthy. He’s passionate about making healthcare more convenient, personalized, and affordable. Prior to joining, Dr. Liu was a practicing primary-care doctor for fifteen years at Kaiser Permanente in Roseville, California. He also served on the Permanente Medical Group (TPMG) Board of Directors as Vice Chair of the Finance and Audit committee and the Governance committee. Dr. Liu graduated summa cum laude and Phi Beta Kappa from the Wharton School of Business at the University of Pennsylvania. He received his medical degree from the University of Connecticut School of Medicine.
The most common treatment for erectile dysfunction is drugs known as phosphodiesterase-5 (PDE-5) inhibitors. These include tadalafil (Cialis), vardenafil (Levitra), and sildenafil citrate (Viagra). These are effective for about 75% of men with erectile dysfunction. They are tablets that are taken around an hour before sex, and last between 4 and 36 hours. Sexual stimulation is required before an erection will occur. The PDE-5 inhibitors cause dilation of blood vessels in the penis to allow erection to occur, and help it to stay rigid. Men using nitrate medication (e.g. GTN spray or sublingual tablets for angina) should not use PDE-5 inhibitors.
Alprostadil should not be used in men at higher risk for priapism (erection lasting longer than six hours) including men with sickle cell anemia, thrombocytopenia (low platelet count), polycythemia (increased red blood cell count), multiple myeloma (a cancer of the white blood cells), and is contraindicated in men prone to venous thrombosis (blood clots in the veins) or hyperviscosity syndrome who are at increased risk for priapism.
Another potential new treatment consists of penile low-intensity shock wave lithotripsy. This consists of 1500 shocks twice a week for 3–6 weeks. The purpose is to stimulate neovascularisation to the corporal bodies with improvement in penile blood flow and endothelial function. The use of low-intensity shock wave lithotripsy may convert PDE5 inhibitor non-responders to responders.47
Other hormone levels: Measurement of other hormones beside testosterone (luteinizing hormone [LH], prolactin level, and cortisol level) may provide clues to other underlying causes of testosterone deficiency and erectile problems, such as pituitary disease or adrenal gland abnormalities. Doctors may check thyroid levels in some individuals as both hypothyroidism (low thyroid function) and hyperthyroidism (overactive thyroid function) can contribute to erectile dysfunction.
Endocrine evaluation consisting of a morning serum testosterone is generally indicated. Measurement of serum prolactin may be indicated. A low testosterone level merits repeat measurement together with assessment of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and prolactin levels. Other tests may be helpful in excluding unrecognized systemic disease and include a complete blood count, urinalysis, creatinine, lipid profile, fasting blood sugar, and thyroid function studies.
"Data shows the longer you ride, the higher your chance of developing ED in terms of distance per week," Gittens says. If you cycle for exercise or socialization, you don't have to necessarily give it up, just make some modifications. Gittens suggests riding for shorter distances, giving yourself a rest every once in a while, finding a comfortable seat, and getting a bike that’s sized appropriately.
In exchange for political impotence, they would be mostly left alone and allowed to get rich. — Paul Mozur, New York Times, "Inside China’s Dystopian Dreams: A.I., Shame and Lots of Cameras," 8 July 2018 Their suspicion is compounded by rumors that the polio vaccine causes impotence, death and, ironically, paralysis. — Meher Ahmad, New York Times, "Pakistan Has Just One New Polio Case, but Isn’t Declaring Victory Yet," 20 May 2018 Fighting back, even as an exercise in impotence, did a lot for McCain. — Alex Horton, Washington Post, "John McCain rebelled at the Naval Academy — and as a POW — long before he was a Senate maverick," 3 May 2018 Feelings of desperation and impotence are being felt throughout Central America, where the lawlessness, endemic poverty and levels of gang violence akin to war zones that have driven so many families from their homes show little signs of abating. — Washington Post, "Violence keeps Central Americans coming to US despite Trump," 21 June 2018 Uruguay's attacking impotence forced Oscar Tabarez to make two changes before the hour mark, with Nahitan Nandez and Giorgian de Arrascaeta replaced by Carlos Sanchez and Cristian Rodriguez. — SI.com, "Egypt 0-1 Uruguay: La Celeste Start With a Win as Gimenez Header Breaks Pharaohs' Hearts," 15 June 2018 It was fueled by physician ignorance and impotence, the habit of looking askance at patients whose symptoms could not be explained, and the arrival in the U.S. of German psychoanalysts who were disciples of Sigmund Freud. — Jim Carrier, STAT, "Lobotomies were once used to treat this gut disease, part of a shameful medical history," 12 June 2018 That signing's top attribute had better be goal-scoring, because the Sounders simply can't sustain with this level of attacking impotence. — Avi Creditor, SI.com, "The MLS XI, Week 14: Don't Hold Your Breath for an MLS Cup Threematch," 4 June 2018 Prostate cancer surgery in particular can have severe results, including incontinence and impotence. — Steven Petrow, Washington Post, "Watching but not treating cancer can be hard. Sometimes it’s the right approach.," 20 May 2018
Just as certain meds can make it difficult for men to have an orgasm, some can keep the flagpole from even getting raised in the first place. Anti-depressant medications like Prozac and Zoloft, anti-anxiety pills like Valium, high blood pressure medicine like Diuril, and even over-the-counter cold medicines like Sudafed and anti-heartburn pills like Zantac can inhibit erections.
Did you know that erectile dysfunction precedes coronary artery disease in almost 70 percent of cases.2 The arteries in the penis are smaller than those that cause heart disease symptoms, which means they are likely to be affected by blockages sooner. When the arteries in the penis are blocked, keeping an erection will be difficult regardless of your level of arousal.
Erectile dysfunction is the inability to develop or maintain an erection that is rigid enough to allow penetration of the vagina, and therefore functional sexual intercourse. Generally, the term erectile dysfunction is applied if this occurs frequently (75% of the time) over a significant period if time (several weeks to months). If this is the case, the term impotence may also be used.
It is important for clinicians prescribing these drugs to make the patient aware of the action of the drugs especially the fact that they do not result in an immediate erection, and that they do not cause an erection without sexual stimulation. There is frequently a great expectation when men begin using these drugs and it is wise to temper their enthusiasm and explain they do not work immediately, and may not work every time, but also let the patient know that if these drugs do not work, there are other options.
Men with physical causes of ED have options, including such medicines as sildenafil (Viagra®), vardenafil (Levitra®), or tadalafil (Cialis®). Men who use nitroglycerin products and those who should avoid sexual activity because of cardiovascular disease shouldn’t take these drugs. Other treatment modalities include use of a vacuum pump or injection of a substance (papaverine) into the penis to increase blood flow to the penis. Men can also have surgery to put a prosthesis into the penis.
Psychotherapy, marital counseling, or sex therapy may be helpful in treating cases of impotence that have psychological or emotional causes. A range of other treatments exists for cases of impotence that arise from purely physiological causes. These treatments include vacuum devices, penile injections, and penile implants. These mechanical or physically invasive approaches have largely been superseded, however, by the drug sildenafil citrate (trade name Viagra), which is taken in pill form. This drug works by enhancing the effects of nitric oxide, a chemical that, upon sexual stimulation, is normally released to widen the blood vessels supplying the penis. The increased flow of blood through those vessels into certain tissues in the penis causes an erection. See also sexual dysfunction.
The risk of impotence increases with age. It is four-fold higher in men in their 60s compared with those in their 40s according to a study published in the Journal of Urology (2000;163:460-463). Men with less education are also more likely to experience impotence, perhaps because they tend to have less healthy lifestyles, eat a less healthy diet, drink more and exercise less. Physical exercise tends to lessen the risk of impotence.
Psychological processes such as depression, anxiety, and relationship problems can impair erectile functioning by reducing erotic focus or otherwise reducing awareness of sensory experience. This may lead to inability to initiate or maintain an erection. Etiologic factors for erectile disorders may be categorized as neurogenic, vasculogenic, or psychogenic, but they most commonly appear to derive from problems in all three areas acting in concert.
While studies are limited, it has been shown that male sexual dysfunction can also negatively impact the sexual function of female partners. A study comparing the sexual function of women with partners with erectile dysfunction to those without showed that sexual arousal, lubrication, orgasm, satisfaction, pain and total score were significantly lower in those who had partners with erectile dysfunction. Later in that study, a large proportion of the men with erectile dysfunction underwent treatment. Following treatment, sexual arousal, lubrication, orgasm, satisfaction and pain were all significantly increased. It was concluded that female sexual function is impacted by male erection status, which may improve following treatment of male sexual dysfunction.
Qaseem, A., Snow, V., Denberg, T. D., Casey, D. E., Forciea, M. A., Owens, D. K., & Shekelle, P. (2009). Hormonal testing and pharmacologic treatment of erectile dysfunction: A clinical practice guideline from the American College of Physicians. Annals of internal medicine, 151(9), 639-649. Retrieved from http://annals.org/aim/article/745155/hormonal-testing-pharmacologic-treatment-erectile-dysfunction-clinical-practice-guideline-from