The somatosensory pathways for erections originate in the penile skin, glans and urethra. Glans afferent sensory free nerve endings are 10-fold more than their corpuscular receptors, and are derived from Aδ and unmyelinated C fibers. The nerve endings coalesce to form the dorsal penile nerve along with other sensory nerve fibers. Through the pudendal nerve they enter the S2-4 nerve roots to terminate on spinal neurons and interneurons. The dorsal nerve is not purely somatic, however. Nerve bundles within the dorsal nerve contain nitric oxide (NO) synthase, found typically in autonomic nerves, and stimulation of the sympathetic chain can leak to evoked potentials from the dorsal nerve and vice versa (10-12).
The penis contains three cylinders, the two corpora cavernosa, which are on the top of the penis (see figure 1 below). These two cylinders are involved in erections. The third cylinder contains the urethra, the tube that the urine and ejaculate passes through, runs along the underside of the penis. The corpus spongiosum surrounds the urethra. Spongy tissue that has muscles, fibrous tissues, veins, and arteries within it makes up the corpora cavernosa. The inside of the corpora cavernosa is like a sponge, with potential spaces that can fill with blood and distend (known as sinusoids). A layer of tissue that is like Saran Wrap, called the tunica albuginea, surrounds the corpora. Veins located just under the tunica albuginea drain blood out of the penis.
Alprostadil is an FDA-approved erectile dysfunction drug that can be injected directly into the penis to trigger an automatic erection. "Penile injection is the most effective type of ED treatment for men who can't take oral treatment," says Nelson Bennett, MD, a urologist at the Lahey Clinic in Burlington, Mass. In fact, it has an 85 percent success rate. Possible side effects include a burning sensation and priapism, an erection that lasts more than four hours and requires medical treatment.

There are myriad factors, both mental and physical, that may contribute to your erectile dysfunction symptoms. Some of the most common impotence causes include diabetes, hypertension, prostate problems, low testosterone and obesity, which can not only put a damper on your sexual enjoyment, but play a key role in your total male vitality, too. (Even medications that are often prescribed to control some of the aforementioned issues can be behind some of the frustrating symptoms of ED.) There are factors like depression, stress and anxiety that can leave you longing for your glory days, and the coping mechanisms like alcohol and tobacco that can make a roll in the sheets less satisfying for you and your partner. We’ll listen to you with a compassionate ear and thoughtfully consider what may be contributing to your ED symptoms, then draw up your perfect, personalized treatment.
Low-intensity extracorporeal shock wave therapy has been proposed as a new non-invasive treatment for erectile dysfunction caused by problems with blood vessels. Shock wave therapy machines are now available in some medical practices in Australia. Although there is some evidence that it may help a proportion of men with erectile dysfunction, more research is needed before clear recommendations on its use can be made.
The observation that TRT enhances the efficacy of PDE5 inhibitors in hypogonadal men taking these therapies with suboptimal response to the PDE5 inhibitors alone has been reported.33 In addition, investigators have demonstrated that TRT in hypogonadal men can improve erectile function even without the benefit of PDE5 inhibitors.33 In addition, guidelines for managing ED in hypogonadal men by the European Association of Urology recommend controlling the man to a eugonadal state prior to initiation of PDE5 inhibitor therapy.36 Testosterone measurement consists of a serum specimen which should be ideally obtained in the morning because of the normal diurnal variation of testosterone which is at its peak in the morning. Since TRT is relatively safe, and men can potentially see an improvement in erectile function, it seems prudent to consider this issue when presented with a patient suffering from ED.

The bad news: Men with diabetes are three times more likely to report having problems with sex than non-diabetic men. The most common sexual problem is Erectile Dysfunction, or ED, sometimes called impotence. Even worse, because ED is such a private issue, many men feel embarrassed to discuss the problem with their doctor, or even their partner, so the problem is never addressed.
What you need to know about STDs Sexually transmitted diseases (STDs) are infections that are passed on from one person to another through sexual contact. There are many STDs, including chlamydia, genital warts, syphilis, and trich. This article looks at some of the most common STDs, the symptoms, and how to avoid getting or passing an STD one on. Read now
ED is a common occurrence after SCI, occurring in up to 80% of men, and results from disruption of the nerve pathways essential for erection (24,25). Different degrees of ED may occur depending on the spinal cord level of injury (LOI), extent of lesion and timing from injury. Reflexogenic erections can occur with lesions above L3 or L4 when the erectile spinal reflex arc remains intact. Psychogenic erections can occur with low lesions in the sacral and lumbar spinal cord but may not occur in complete lesions above T9 that can damage sympathetic outflow. Additionally, reflexogenic erections are not likely to occur in the spinal shock period that occurs after the initial cord trauma. Conversely, their occurrence may signal that the period of shock is over (26). Typically SCI affects younger men in their “sexual prime” and ED is associated with decreased quality of life (27).
So here’s something that’s really fascinating. Healthy eating is a way to reduce anxiety and stress. Now how, you may be asking, right? Well, think about it. We live in a world where there are so many variables and where we don’t have control over our lives. But now, with healthy eating, we have control over what goes into our body. And now having that control empowers us to be even healthier, to be more directive in what we do. And certainly, that begins then to reduce the anxiety and the stress. So all in one, you have a healthier body, but certainly a healthier mind.
5. Medline Plus. US National Library of Medicine. NIH National Institutes of Health. Drugs that may cause impotence (updated 21 Jan 2015). http://www.nlm.nih.gov/medlineplus/ency/article/004024.htm (accessed Nov 2016). myDr myDr provides comprehensive Australian health and medical information, images and tools covering symptoms, diseases, tests, medicines and treatments, and nutrition and fitness.Related ArticlesImpotence treatmentsIf you have impotence (erectile dysfunction), the treatment your doctor recommends will depend on thErectile dysfunction: visiting your doctorFind out what questions a doctor may ask when discussing erectile dysfunction (ED, or impotenceGum disease linked to erectile dysfunctionAdvanced gum disease (periodontitis) has been linked to an increased risk of erectile dysfunction, wPeyronie's diseasePeyronie’s disease is condition where a band of scar tissue forms in the penis, causing aAdvertisement
Penile implants - are generally used if physical damage (like an accident) makes the anatomical parts needed for an erection not work. These are inserted by surgery and can provide a permanent treatment choice if others fail to work. The implants can be semi-rigid or inflatable. They can be pretty expensive and are not usually available on the NHS.

For many of the 30 million Americans affected by erectile dysfunction, Viagra, Levitra, and Cialis are the first line of ED treatment — and they’re successful for about 80 percent of men. These drugs, called phosphodiesterase-5 inhibitors, are approved by the U.S. Food and Drug Administration (FDA) and work by increasing blood flow to an erection. Common side effects include nasal congestion and headache. Note: If you take nitroglycerin pills for heart disease, you won’t be able to take ED pills, as they can cause a dangerous drop in blood pressure.

In a prospective study from the Prostate Cancer Prevention Trial database, Thompson et al reported that men presenting with ED had a significantly higher chance of developing a cardiovascular event over a 7-year follow-up period. [55] The hazard ratio was 1.45, which is in the range of risk associated with current smoking or a family history of MI.


"Erectile dysfunction can be a very serious issue because it's a marker of underlying cardiovascular disease, and it often occurs before heart conditions become apparent. Therefore, men should consider improving their weight and overall nutrition, exercise more, drink less alcohol and have a better night's sleep, as well as address risk factors such as diabetes, high blood pressure and cholesterol.


Organic ED involves abnormalities the penile arteries, veins, or both and is the most common cause of ED, especially in older men. When the problem is arterial, it is usually caused by arteriosclerosis, or hardening of the arteries, although trauma to the arteries may be the cause. The controllable risk factors for arteriosclerosis--being overweight, lack of exercise, high cholesterol, high blood pressure, and cigarette smoking--can cause erectile failure often before progressing to affect the heart. 
One study examined the role of testosterone supplementation in hypogonadal men with ED. These men were considered nonresponders to sildenafil, and their erections were monitored by assessing nocturnal penile tumescence (NPT). After these men were given testosterone transdermally for 6 months, the number of NPTs increased, as did the maximum rigidity with sildenafil. [18] This study suggests that a certain level of testosterone may be necessary for PDE5 inhibitors to function properly.
Erosion of the prosthesis, whereby it presses through the corporal tissue into the urethra, may occur. Symptoms and signs may include pain, blood in the urine, discharge, abnormal urine stream, and malfunction. If the prosthesis erodes into the urethra, a physician must remove it. If the other cylinder remains intact, it can be left in place. A physician leaves a catheter in place to allow the urethra to heal.

This content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), part of the National Institutes of Health. The NIDDK translates and disseminates research findings through its clearinghouses and education programs to increase knowledge and understanding about health and disease among patients, health professionals, and the public. Content produced by the NIDDK is carefully reviewed by NIDDK scientists and other experts.
Alprostadil is a potent vasodilator and smooth muscle relaxant identical to the naturally occurring PGE1. PGE1 binds with specific receptors on smooth muscle cells and activates intracellular adenylate cyclase to produce cAMP, which in turn induces tissue relaxation through a second messenger system (96). PGE1 is the only FDA approved form of intracavernosal therapy and is available commercailly as EDEX, or Caverject. Its efficacy was demonstrated in several clinical trials where the rate of responders ranged from 40% to 80% (97,98). The most common adverse event is penile pain, which is not related to the injection of the medication itself. In men with prolonged use the pain is usually self-limited (99).

Many common medications for treating hypertension, depression, and high blood lipids (high cholesterol) can contribute to erectile dysfunction (see above). Treatment of hypertension is an example. There are many different types (classes) of medications for high blood pressure; these include beta-blockers, calcium channel blockers, diuretics (medications that increase urine volume), angiotensin converting enzyme inhibitors (ACE inhibitors), and angiotensin receptor blockers (ARBs). Patients may use these medications alone or in combination to control blood pressure. Some of these medications can cause troubles with erections. For example, Inderal (a beta-blocker) and hydrochlorothiazide (a diuretic) cause erectile dysfunction, while calcium channel blockers and ACE inhibitors do not seem to affect erectile function. On the other hand, other medications (such as angiotensin receptor blockers [ARB] including losartan [Cozaar] and valsartan [Diovan]) may actually help with erections. Therefore, if possible, you may benefit from changing your medications, but this requires approval by your prescribing health care provider.
Alprostadil may also be administered into the urethral opening of the penis. In MUSE (medical urethral system for erection), the man inserts a thin tube the width of a vermicelli noodle into his urethral opening and presses down on a plunger to deliver a tiny pellet containing alprostadil into his penis. The drug takes about 10 minutes to work and the erection lasts about an hour. The main side effect is a sensation of pain and burning in the urethra, which can last about five to 15 minutes.
The dorsal artery provides for engorgement of the glans during erection, whereas the bulbourethral artery supplies the bulb and the corpus spongiosum. The cavernous artery effects tumescence of the corpus cavernosum and thus is principally responsible for erection. The cavernous artery gives off many helicine arteries, which supply the trabecular erectile tissue and the sinusoids. These helicine arteries are contracted and tortuous in the flaccid state and become dilated and straight during erection. [9]
Infection is a concern after placement of a prosthesis and is a reported complication in 8%-20% of men undergoing placement of a penile prosthesis. If a prosthesis becomes infected (redness, pain, and swelling of the penis and sometimes purulent drainage are signs of infection), the prosthesis must be removed. Depending on the timing and severity of the infection and your surgeon's preference, the area can be irrigated extensively with antibiotic solutions and a new prosthesis placed at the same time or removal of the infected prosthesis and an attempt to place a new prosthesis made at a later time when the infection is totally cleared.
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.

Alprostadil is a potent vasodilator and smooth muscle relaxant identical to the naturally occurring PGE1. PGE1 binds with specific receptors on smooth muscle cells and activates intracellular adenylate cyclase to produce cAMP, which in turn induces tissue relaxation through a second messenger system (96). PGE1 is the only FDA approved form of intracavernosal therapy and is available commercailly as EDEX, or Caverject. Its efficacy was demonstrated in several clinical trials where the rate of responders ranged from 40% to 80% (97,98). The most common adverse event is penile pain, which is not related to the injection of the medication itself. In men with prolonged use the pain is usually self-limited (99).
Due to the risk of hypotension, caution should be used in patients using alpha blockers for prostate hyperplasia and patients using other antihypertensive medications and alpha blockers, which should not be co-administered with PDE5 inhibitors. In patients who take 50 mg of sildenafil or more and use alpha blockers, sildenafil dosing should be avoided for at least 4 hours after the dose of the alpha blocker. In patients who take 25 mg of sildenafil, use of any alpha blockers is considered safe.
Penis pumps produce erections by drawing blood, via air suction, into the penis. The devices consist of a cylindrical tube, 12 to 18 inches long, connected by a small air hose to a hand pump (on many models this resembles the squeeze mechanism on a blood pressure monitor). Users place the tube over the penis then pump to produce an erection. They must then place an elastic band around the base of the penis to keep the blood there and maintain the erection.  
• Blood Vessels: Diabetes damages blood vessels, especially the smallest blood vessels such as those in the penis. Diabetes can also cause heart disease and other circulatory problems. Proper blood flow is absolutely crucial to achieving erection. “Erection is a hydraulic phenomenon that occurs involuntarily,” says Arturo Rolla, MD, of Harvard University School of Medicine. “Nobody can will an erection!” Anything that limits or impairs blood flow can interfere with the ability to achieve an erection, no matter how strong one’s sexual desire.

Penile Injection Medication: This is just what it sounds like. Injected at home directly into the penis, the medication alprostadil produces erection by relaxing certain muscles, increasing blood flow into the penis and restricting outflow. Although some sources report an 80 percent success rate, the therapy has disadvantages, such as risks of infection, pain, and scarring—fibrosis—in the penis, and it may also cause priapism. A popular version of this medication is Upjohn Corporation’s Caverject. The MUSE System, by VIVUS, involves the same medicine (a pellet of alprostadil) applied with an eye-dropper-like applicator, directly into the urethra.
Much of the emphasis on erectile pathophysiology has been placed on penile smooth muscle function and cavernosal hemodynamics. The neuroanatomy and neurophysiology of erection can be characterized but its full extent is poorly understood. Neurologic disease does not always reproducibly affect erections in a uniform manner compared to other types of sexual dysfunction (SD). This offers many obstacles to understanding the role the nervous systems plays in SD and consequently obscures what treatment options readily optimize erections specific to the neurologic insult.
On the horizon is gene therapy that would deliver genes that produce products or proteins that may not be functioning properly in the penile tissue of men with ED. Replacement of these proteins may result in improvement in erectile function. Experimental animal models have demonstrated improvement in erectile function with gene therapy. Human studies may also demonstrate success with this therapy. Gene therapy may take a long time for regulatory approval and public acceptance.
ED varies in men with seizure disorders, occurring in 3% to 58% of men with epilepsy (30). The cause of ED is likely multifactorial, with neurologic, endocrine, iatrogenic, psychiatric and psychosocial factors leading to varying degrees of ED (31). ED can occur in periods surrounding active seizures (ictal) or in the periods unrelated to seizure activity (post-ictal) as well (32).
Erectile dysfunction is defined as the persistent inability to achieve or maintain penile erection sufficient for satisfactory sexual performance. The Massachusetts Male Aging Study surveyed 1,709 men aged 40–70 years between 1987 and 1989 and found there was a total prevalence of erectile dysfunction of 52 percent. It was estimated that, in 1995, over 152 million men worldwide experienced ED. For 2025, the prevalence of ED is predicted to be approximately 322 million worldwide.

A common and important cause of ED is vasculogenic. Many men with ED have comorbid conditions such as hyperlipidemia, hypercholesterolemia, tobacco abuse, diabetes mellitus, or coronary artery disease (CAD). [6] The Princeton III Consensus recommends screening men who present with ED for cardiovascular risk factors; ED may be the earliest presentation of atherosclerosis and vascular disease. [7]
The dorsal artery provides for engorgement of the glans during erection, whereas the bulbourethral artery supplies the bulb and the corpus spongiosum. The cavernous artery effects tumescence of the corpus cavernosum and thus is principally responsible for erection. The cavernous artery gives off many helicine arteries, which supply the trabecular erectile tissue and the sinusoids. These helicine arteries are contracted and tortuous in the flaccid state and become dilated and straight during erection. [9]

However, in contrast, a recent systematic review of published studies, the authors concluded that overall, the addition of testosterone to PDE-5 inhibitors might benefit patients with ED associated with testosterone levels of less than 300 ng/dL (10.4 nmol/L) who failed monotherapy. [20] A limitation of existing studies are their heterogeneous nature and methodological drawbacks.

Diabetes. Erectile Dysfunction is common in people with diabetes. An estimated 10.9 million adult men in the U.S. have diabetes, and 35 to 50 percent of these men are impotent. The process involves premature and unusually severe hardening of the arteries. Peripheral neuropathy, with involvement of the nerves controlling erections, is commonly seen in people with diabetes.
The role of the endothelium in erectile function became clearer with the observation that the phosphodiesterase type 5 (PDE5) inhibitor, sildenafil, enhanced erectile function. Erection occurs with the release of nitric oxide (NO) from the vascular endothelial cells.17 The reduction in endothelial cell production of NO results in the negative impact on the smooth muscles in the corporal bodies and results in less relaxation of the smooth muscle cells with decrease in blood supply and resulting ED. A similar phenomenon is well known to impact the coronary arterial system resulting in CVD.
Some self-administered measures may be useful in the primary care setting to screen for and evaluate the degree of ED.12 The most commonly used instrument is the International Index of Erectile Function, a 15-item questionnaire that has been validated in many populations and is considered the gold standard to evaluate patients for ED.13 The Sexual Health Inventory for Men is a short-form, 5-item questionnaire developed to monitor treatment progress.12 It is important to recognize that short-form questionnaire does not evaluate specific areas of the sexual cycle, such as sexual desire, ejaculation, and orgasm; however, it may be useful in discussing ED with patients and evaluating treatment results over time.
Effective treatment for erectile dysfunction is available, and for most men will allow the return to a fulfilling sex life. The side effects of the treatment for erectile dysfunction vary depending on the treatment that is used. Some may interrupt the spontaneity of sexual activity. For example, PDE-5 inhibitors typically need to be taken one hour before sex. Side effects may include headaches, indigestion, vasodilation, diarrhoea and blue tinge to vision. Other treatments such as penile injections may cause pain at the injection site, or an erection that will not go down. Treatment options need to be carefully discussed with your doctor to determine which one is best suited to you.
In one study, 9.6% reported ‘occasional’ erectile dysfunction, 8.9% reported erectile dysfunction occurring ‘often’, and 18.6% reported erectile dysfunction occurring ‘all the time’. Of these, only 11.6% had received treatment.In another study, only 14.1% of men reported that they had received treatment, despite experiencing erectile dysfunction for longer than 12 months.
Size matters, so get slim and stay slim. A trim waistline is one good defense — a man with a 42-inch waist is 50% more likely to have ED than one with a 32-inch waist. Losing weight can help fight erectile dysfunction, so getting to a healthy weight and staying there is another good strategy for avoiding or fixing ED. Obesity raises risks for vascular disease and diabetes, two major causes of ED. And excess fat interferes with several hormones that may be part of the problem as well.
VED involved placing the penis in a clear plastic tube where negative pressure created by the vacuum pump leads to penile engorgement and tumescence. Usually a constriction ring can be placed on the base of penis following penile engorgement. Some men complain of bruising, a “cold” penis and pain associated with the constriction ring; however, in some men with NED sensation may not be intact mitigating the side effects of VEDs. VEDs have reported effectiveness up to 90% in certain ED populations and it remains a non-invasive means to achieve and erection.
Vascular damage may result from radiation therapy to the pelvis and prostate in the treatment of prostate cancer. [36] Both the blood vessels and the nerves to the penis may be affected. Radiation damage to the crura of the penis, which are highly susceptible to radiation damage, can induce ED. Data indicate that 50% of men undergoing radiation therapy lose erectile function within 5 years after completing therapy; fortunately, some respond to one of the PDE5 inhibitors.

Whenever I am prescribing a medication to a patient, I’m always asking myself, what can the patient do before requiring the medication? What changes do they have to make in order to reduce the amount of medication or preclude their even needing it? So a good candidate is somebody who has an understanding of a healthy lifestyle, about physical activity, about sleep, about nutrition, alcohol, smoking. So patients, individuals, have to do their share before they’re a candidate for anything. All right?

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