PDE5 inhibitors, the primary second-line therapy, have been the mainstay of ED treatment since the release of sildenafil (Viagra) in 1998, with the subsequent development of many others, and still more in the development stage. These medications do improve erectile quality for the majority of men, and they work by enhancing blood flow in the corpora cavernosa. These medications are generally used on demand and need to be taken about an hour before sexual intimacy. Tadalafil (Cialis) is longer acting and does come in a daily preparation potentially eliminating the ‘on-demand’ need. The daily dosing of tadalafil, 2.5–5 mg\day, has also been approved by the FDA for treatment of symptoms of BPH.41 PDE5 inhibitors are contraindicated in men taking nitrates, but otherwise PDE5 inhibitors are very safe and effective. When PDE5 inhibitors are coadministered with nitrates, pronounced systemic vasodilation and severe hypotension are possible. Many patients with ED are elderly and have the same risk factors as patients with CAD, so these drug combinations are commonly considered or encountered in clinical practice.42
A vacuum erection device is a plastic tube that slips over the penis, making a seal with the skin of the body. A pump at the other end of the tube makes a low-pressure vacuum around the erectile tissue, which results in an erection. An elastic ring is then slipped onto the base of the penis. This holds the blood in the penis (and keeps it hard) for up to 30 minutes. With proper training, 75 out of 100 men can get a working erection using a vacuum erection device.
Sildenafil (Viagra) was the first oral phosphodiesterase type 5 (PDE5) inhibitor approved by the FDA in the United States for the treatment of erectile dysfunction (it is not approved for women). Sildenafil inhibits PDE5, which is an enzyme that destroys cGMP. By inhibiting the destruction of cGMP by PDE5, sildenafil allows cGMP to accumulate. The cGMP in turn prolongs relaxation of the smooth muscle of the corpora cavernosa. Relaxation of the corpora cavernosa smooth muscle allows blood to flow into the penis resulting in increased engorgement of the penis. In short, sildenafil increases blood flow into the penis and decreases blood flow out of the penis.
In this study, ED proceeded CVD in almost 70% of cases. Similarly, many men with ED have been found to have pre-existing CVD. A study by Vlachopoulos et al evaluated the incidence of asymptomatic CVD in 50 men with ED.22 These authors found that 19% of men with ED had asymptomatic CVD. Similarly, Mulhall and colleagues found that 20% of men presenting with ED and vascular insufficiency on penile duplex had asymptomatic CVD.23
Since endothelial dysfunction, CVD and ED are closely associated in epidemiological studies, the question for clinicians is whether to recommend the man presenting with ED undergo a cardiovascular (CV) evaluation. Clearly, based on numerous studies, ED can be considered at least a ‘marker’ for possible further vascular disease or CVD.15 In their report, Vlachopoulos and coworkers make the point that the man presenting with ED, the clinician, is offered an opportunity to attempt to improve the health of the man by addressing lifestyle modification, and consider further vascular evaluation owing to the clear relationship between endothelial dysfunction, ED and CVD.19
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.
You’ve probably heard of Viagra, but it’s not the only pill for ED. This class of drugs also includes Cialis, Levitra, Staxyn, and Stendra. All work by improving blood flow to the penis during arousal. They're generally taken 30-60 minutes before sexual activity and should not be used more than once a day. Cialis can be taken up to 36 hours before sexual activity and also comes in a lower, daily dose. Staxyn dissolves in the mouth. All require an OK from your doctor first for safety.
SD in MS can be classified into three categories. Primary SD is due directly due to MS-related neurological deficits, secondary SD is related to physical impairments and symptoms or drugs used for MS treatment, and tertiary SD is due to the psychological, social and cultural problems attributed to MS (38). These classifications are important, and underscore the importance of addressing all the issues leading to SD not just the neurologic impairment.
Ultrasound with Doppler imaging (ultrasound plus evaluation of blood flow in the arteries and veins) can provide additional information about blood flow of the penis and may help in the evaluation of patients prior to surgical intervention. This study is typically performed after the injection of a chemical that causes the arteries to open up, a vasodilator (prostaglandin E1), into the corpora cavernosa in order to cause dilation of blood vessels and promote blood flow into the penis. The rate of blood flow into the penis can be measured along with an evaluation of problems with compression of the veins.
Diabetes is an example of an endocrine disease that can cause a person to experience impotence. Diabetes affects the body’s ability to utilize the hormone insulin. One of the side effects associated with chronic diabetes is nerve damage. This affects penis sensations. Other complications associated with diabetes are impaired blood flow and hormone levels. Both of these factors can contribute to impotence.
ED usually has something physical behind it, particularly in older men. But psychological factors can be a factor in many cases of ED. Experts say stress, depression, poor self-esteem, and performance anxiety can short-circuit the process that leads to an erection. These factors can also make the problem worse in men whose ED stems from something physical.
Your doctor will ask you questions about your symptoms and health history. They may do tests to determine if your symptoms are caused by an underlying condition. You should expect a physical exam where your doctor will listen to your heart and lungs, check your blood pressure, and examine your testicles and penis. They may also recommend a rectal exam to check your prostate. Additionally, you may need blood or urine tests to rule out other conditions.
Psychosocial problems are important and may cause erectile dysfunction by themselves or together with other causes of erectile dysfunction, such as diabetes and heart disease. Relationships are complicated and many factors cause tensions, which can affect sexual relations. For some men, these problems can become ongoing and it can help to talk through the issue with a skilled counsellor. It is important to know that the longer erectile dysfunction is left untreated, the greater the effect on relationships. This is another reason why early treatment of erectile dysfunction is important.
A variety of personal habits and lifestyle choices have been linked to ED. In some ways, this is a good thing, since habits can be broken and choices reconsidered. What's more, many of the lifestyle factors that contribute to sexual problems are ones that affect overall health and well-being, both physical and mental. Addressing these factors, therefore, can have benefits beyond improving erectile dysfunction.
It is essential to discuss erectile dysfunction with your doctor, so any serious underlying causes can be excluded and treatment options can be discussed. Many men are embarrassed discussing this issue with their doctor, or even their partner. Open communication with your doctor, and in your relationship, is important for effectively managing this common problem.
Other medical therapies under evaluation include ROCK inhibitors and soluble guanyl cyclase activators. Melanocortin receptor agonists are a new set of medications being developed in the field of erectile dysfunction. Their action is on the nervous system rather than the vascular system. PT-141 is a nasal preparation that appears to be effective alone or in combination with PDE5 inhibitors. The main side effects include flushing and nausea. These drugs are currently not approved for commercial use.
When other treatments haven’t helped, a penile implant may be the right solution. A penile implant is a medical device that is surgically placed into a penis to mimic the look and performance of a natural erection9. Implants are custom-fitted to your anatomy. Sensitivity and the ability to ejaculate aren’t typically affected either, so you’ll be able to have an orgasm normally (unless you have a medical condition that prevents this)7.
All NOS subtypes produce NO, but each may play a different biologic role in various tissues. nNOS and eNOS are considered constitutive forms because they share biochemical features: They are calcium-dependent, they require calmodulin and reduced nicotinamide adenine dinucleotide phosphate for catalytic activity, and they are competitively inhibited by arginine derivatives. nNOS is involved in the regulation of neurotransmission, and eNOS is involved in the regulation of blood flow.
Implantable penile prostheses are usually considered a last resort for treating impotence. They are implanted in the corpora cavernosa to make the penis rigid without the need for blood flow. The semirigid type of prosthesis consists of a pair of flexible silicone rods that can be bent up or down. This type of device has a low failure rate but, unfortunately, it causes the penis to always be erect, which can be difficult to conceal under clothing.
The venous constriction device is a device designed to compress the veins that drain blood flow out of the penis to keep blood in the penis. These devices may help individuals who have a "venous leak." In these individuals, although blood flow is coming into the penis, it is draining out at the same time and this persistent drainage prevents a fully rigid erection. These devices may be used with other forms of medical therapy, such as medications, injection therapy, or the vacuum device.
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
Testosterone replacement therapy may improve energy, mood, and bone density, increase muscle mass and weight, and heighten sexual interest in older men who may have deficient levels of testosterone. Testosterone supplementation is not recommended for men who have normal testosterone levels for their age group due to the risk of prostate enlargement and other side effects. Testosterone replacement therapy is available as a cream or gel, topical solution, skin patch, injectable form and pellet form placed under the skin.
And surgery comes with its own serious risks, such as developing incontinence or impotence, while radiation can result in urinary problems. — Peter Loftus, WSJ, "Surgery Adds Three Years to Lives of Prostate-Cancer Patients, Study Finds," 12 Dec. 2018 Male-impotence pill Viagra began facing generic competition late last year, while the Lyrica pain treatment is expected to confront generics at the end of this year. — Jonathan D. Rockoff, WSJ, "Pfizer Narrows Guidance on Tougher Pricing, Generic Competition," 30 Oct. 2018 Arkham Horror Third Edition is a classic struggle of agency versus impotence, set in the uncanny world of H.P. Lovecraft’s Cthulhu mythos. — Charlie Theel, Ars Technica, "Arkham Horror Third Edition: The classic Lovecraft adventure returns," 24 Nov. 2018 There’s obviously a lot of anger and frustration here toward the US government at the moment—along with side effects like bottled rage and sometimes a creeping sense of ineptitude or impotence about our ability to do anything about it. — Corey Seymour, Vogue, "Pussy Riot's Nadya Tolokonnikova On Her New Guide To Activism, Raising The Next President Of Russia, And Her "Holy War" On Fairy Tales," 12 Oct. 2018 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
The role of the endothelium in ED has been noted for a number of years and the overlapping of ED and other conditions, especially coronary heart disease, CVD, affecting endothelial function/dysfunction, is clearly present. The endothelial cell is now known to affect vascular tone and impact the process of atherosclerosis, and impacting ED, CVD and peripheral vascular disease.16
Although not proven, it is likely that erectile dysfunction can be prevented by good general health, paying particular attention to body weight, exercise, and cigarette smoking. For example, heart disease and diabetes are problems that can cause erectile dysfunction, and both are preventable through lifestyle changes such as sensible eating and regular exercise. Furthermore, early diagnosis and treatment of associated conditions like diabetes, hypertension and high cholesterol may prevent or delay erectile dysfunction, or stop the erectile dysfunction from getting more serious.
An occasional problem achieving an erection is nothing to worry about. But failure to do so more than 50% of the time at any age may indicate a condition that needs treatment. About 40% of men in their 40s report at least occasional problems getting and maintaining erections. So do more than half (52%) of men aged 40 to 70, and about 70% of men in their 70s.
ED can also occur as a side effect of some medications, for example some high blood pressure medications such as certain diuretics and beta blockers. If you think that a medication you are taking has a negative effect on your sex life, you should discuss this with your prescribing doctor. Your doctor may be able to recommend an alternative treatment.
A number of herbs have been promoted for treating impotence. The most widely touted herbs for this purpose are Coryanthe yohimbe (available by prescription as yohimbine, with the trade name Yocon) and gingko (Gingko biloba), although neither has been conclusively shown to help the condition in controlled studies. In addition, gingko carries some risk of abnormal blood clotting and should be avoided by men taking blood thinners such as coumadin. Other herbs promoted for treating impotence include true unicorn root (Aletrius farinosa), saw palmetto (Serenoa repens), ginseng (Panax ginseng), and Siberian ginseng (Eleuthrococcus senticosus). Strychnos Nux vomica has been recommended, especially when impotence is caused by excessive alcohol, cigarettes, or dietary indiscretions, but it can be very toxic if taken improperly, so it should be used only under the strict supervision of a physician trained in its use.
Additionally, the physiologic processes involving erections begin at the genetic level. Certain genes become activated at critical times to produce proteins vital to sustaining this pathway. Some researchers have focused on identifying particular genes that place men at risk for ED. At present, these studies are limited to animal models, and little success has been reported to date.  Nevertheless, this research has given rise to many new treatment targets and a better understanding of the entire process.
The PDE5 inhibitors sildenafil (Viagra), vardenafil (Levitra) and tadalafil (Cialis) are prescription drugs which are taken orally.:20–21 Additionally, a cream combining alprostadil with the permeation enhancer DDAIP has been approved in Canada as a first line treatment for erectile dysfunction. Penile injections, on the other hand, can involve one of the following medications: papaverine, phentolamine, and prostaglandin E1, also known as alprostadil.:25