Clinical experience in switching medications to improve ED has been disappointing in that improvement does not often occur. Nonetheless, it is important to try to discontinue possible offending medications before proceeding to more invasive ED treatment options. Oral ED medications have changed the way clinicians discontinue medications in patients with ED and has improved the approach. For example, a patient may develop ED on a thiazide diuretic. The diuretic may be withdrawn, but a trial of oral ED therapy can be initiated during the observation period while the patient is waiting to see if any spontaneous improvement in ED occurs after drug withdrawal. Alternatively, if diuretic therapy is effective, well tolerated, and controlling blood pressure, oral ED therapy can be used on an ongoing basis to treat the side effect of ED.
The Massachusetts Male Aging Study (MMAS) documented an inverse correlation between ED risk and high-density lipoprotein (HDL) cholesterol levels but did not identify any effect from elevated total cholesterol levels.  Another study involving male subjects aged 45-54 years found a correlation with abnormal HDL cholesterol levels but also found a correlation with elevated total cholesterol levels. The MMAS included a preponderance of older men.
There are so many potential reasons a man might develop erectile dysfunction (ED), it's nearly impossible to generalize the best ways to treat it. What works for one man may not work for another simply because they are having problems for different reasons. That said, it may encouraging to hear that there are a variety of options that may be considered, from psychological counseling to lifestyle changes, medications to treatments and devices.
Finally, gene therapy and stem cell research has widened the frontier of ED treatment proposed as possibility to even reverse ED. Specifically, gene therapy pertains to repairing the cause of ED by restoring defective gene function and/or altering the expression of the mutant gene (32). Most of the available data on gene therapy are in the animal model. However, a phase I clinical trial in men with ED undergoing intracavernous injection with a DNA plasmid carrying the alpha-subunit of the corporal smooth muscle Maxi-K channel showed promise in increased erectile function based on IIEF assessment sustained throughout the 3-month study period (122).
CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is sage, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.
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).
In fact, one common reason many younger men visit their doctor is to get erectile dysfunction medication. Often, men with erectile dysfunction suffer with diabetes or heart disease, or may be sedentary or obese, but they don’t realize the impact of these health conditions on sexual function. Along with erectile dysfunction treatment, the doctor may recommend managing the illness, being more physically active, or losing weight.
Impotence, also known as erectile dysfunction or ED, is a very common problem, affecting up to half of 40-70 year old men in Australia.Treatment techniques for impotence have varied through the years, from external steel mechanical attachments, to static electricity attached to the penis and testicles, to simple aphrodisiacs such as oysters. Until as recently as 1970, erectile failure was almost always seen as being due to psychological causes and was usually treated with psychotherapy.Since then, the medical causes contributing to impotence have been recognised and the treatment of impotence has been revolutionised, providing a range of options which are far more acceptable and very much more successful.Treatment options for impotenceTreatment choices for erectile dysfunction include:medicines;self-injection therapy;devices such as vacuum pumps;penile implant surgery;hormone therapy; andcounselling.If you have erectile dysfunction, the treatment your doctor recommends will depend on the severity of symptoms and the underlying cause of your impotence.Your doctor will want to check that any conditions that could be contributing to or causing erectile dysfunction are being treated.Your doctor may also suggest that you make some lifestyle adjustments, such as:increasing the amount of physical activity you get;losing weight if you are overweight;reducing the amount of alcohol you drink;quitting smoking; andnot taking illicit drugs.These lifestyle recommendations can help improve impotence related to several causes and improve your health in general.Medicines for erectile dysfunctionThe first tablet available for erectile dysfunction, sildenafil (brand name Viagra), has been largely responsible for helping to bring the topic of erectile dysfunction out into the open. Similar medications — tadalafil (Cialis) and vardenafil ( Levitra) — are also available. These medicines all work in a similar way, although there is some difference in how long their effect lasts. Sildenafil, tadalafil and vardenafil belong to a group of medicines called phosphodiesterase type 5 (PDE5) inhibitors because they block the PDE5 enzyme.How do oral medicines help treat erectile dysfunction?PDE5 inhibitors help in the process of getting and keeping an erection by working on chemicals in the body that are involved in erections. These medicines work by stopping PDE5 from breaking down an erection-producing chemical called cyclic guanosine monophosphate (cGMP). cGMP helps to relax the smooth muscle cells in the penis's erectile tissue, allowing more blood to flow into the penis to cause an erection. When PDE5 is temporarily blocked by these medicines, it can’t break down the erection producing cGMP, so an erection can be achieved and maintained. PDE5 inhibitors can be used in the treatment of erectile dysfunction that is due to physical or psychological causes.Medications such as Viagra, Cialis and Levitra will work only if you are sexually stimulated. They are not aphrodisiacs and won’t increase your sex drive.Side effects of PDE5 inhibitorsSide effects of these medicines can include headaches, flushes, blocked nose, indigestion and dizziness.In rare situations, sildenafil and vardenafil can cause a distortion of vision or change in colour vision.Tadalafil has been associated with back pain.Who can take medicines for impotence?PDE5 inhibitors cannot be taken by all men, so your doctor will need to evaluate your suitability before prescribing either of these medications.Men taking nitrates (often used to treat angina) should never take phosphodiesterase type 5 (PDE5) inhibitors. PDE5 inhibitors should also not be taken with some medicines used to treat high blood pressure.PDE5 inhibitors may also not be suitable for men with certain heart conditions or low blood pressure. Check with your doctor to find out if this type of medication may be suitable for you.Self-injection therapySelf-injection therapy delivers a medicine called alprostadil (brand name Caverject), also known as prostaglandin E-1, to the erectile tissue of the penis. Prostaglandin E-1 occurs naturally in the body and helps increase the blood flow to the penis to cause an erection. Unlike the PDE5 inhibitors, alprostadil will cause an erection whether the penis is stimulated or not.Self-injection therapy is usually recommended if PDE5 inhibitor medicines are not suitable or have not been effective in the treatment of erectile dysfunction.How to use self-injection therapyAlprostadil is injected into either of the 2 cigar-shaped chambers of the penis known as the corpora cavernosa, which run along the length of the penis, one on either side. Your doctor or urologist (specialist in problems with male reproductive organs and the urinary tract) will give you instructions on how to do this.Alprostadil should produce an erection in 5 to 20 minutes and, generally, the erection will last for 30 to 60 minutes.You should not use alprostadil more than once in a 24-hour period, and you should use it no more than 3 times a week.Don’t try to use more than the recommended dose of alprostadil, as your erection may last longer than is medically safe.Who can use self-injection therapy?You should ask your doctor if alprostadil is suitable for you. Your doctor will also be able to tell you how much alprostadil to use, depending on your condition and whether or not you are taking any other medications, and also how to use alprostadil properly.People with certain illnesses, such as leukaemia and sickle cell anaemia, or who have a penile implant or Peyronie’s disease, where the penis may be scarred and produces erections that are not straight, should not use alprostadil.Men for whom sexual activity is not advised should not use alprostadil.Side effects of injection therapyThe most common side effects of alprostadil include pain in the penis or bruising in the penis at the site of injection. Fibrosis (the development of fibrous tissue) can also develop following injections into the penis.The most serious side effect is priapism (a persistent erection), which is a medical emergency. Your doctor will inform you of what to do if you have an erection that persists for 2 hours or more. It is very important that you follow your doctor’s instructions and inform them that you have experienced this side effect.Vacuum erection devicesVacuum erection devices work by creating a vacuum, which increases blood flow to the penis, producing an erection.The penis is lubricated and placed inside a hollow plastic chamber. Air is pumped out of the chamber, either manually or by a battery powered pump. This creates a vacuum which pulls blood into the penis to cause an erection. This takes about 5 minutes.Once the penis is erect, the man fits a rubber ring around the base of his penis to keep the blood trapped inside the penis when the cylinder is removed. After intercourse, the ring can be removed to return the penis to a limp state.Vacuum erection devices avoid surgery and can be used as often as required. However, they may be difficult to use, and many men and their partners feel they take much of the pleasure and spontaneity away from sexual activities. Vacuum pumps are not suitable for men who have problems with blood clotting, or blood disorders such as leukaemia.Penile implant surgery for impotencePenile implant surgery is not a common procedure but in some cases it may be the most appropriate treatment for erectile dysfunction.The procedure involves placing an implant inside the penis, along its length, so that it can become erect. The implant may be a pair of semi-rigid rods or a pair of inflatable cylinders.The inflatable implants allow the penis to look and feel limp (flaccid) or erect, depending on how much the cylinders are inflated. The cylinders in an inflatable implant are hollow, and the man gets an erection by squeezing a pump located in his scrotum to fill the cylinders with salt water (saline) stored in a reservoir implanted in his lower abdomen. A release valve drains the saline out of the cylinders and back into the reservoir.With the semi-rigid, malleable rod type of implant, the rods run along the length of the penis and can be bent upwards to produce an erect penis, or downwards when an erect penis is not required.Like all surgery, there are some risks, such as infection or bleeding. If you have had surgery and have severe pain, fever, swelling or excessive bleeding, you should contact your doctor as soon as possible.Vascular surgery for erectile dysfunctionIn cases where a man’s anatomy prevents blood flow into or out of the penis, vascular surgery may be an option. This treatment option is rarely recommended, and is usually only successful in younger men.If there is a blockage that prevents blood from flowing into the penis, a doctor may recommend an operation that bypasses the blocked blood vessels, using a length of vein or manufactured tubing, to allow more blood to flow into the penis and help produce an erection.If the problem is that blood leaks back out of the penis, this can be corrected by tying off the major veins that drain the penis, a procedure known as venous ligation.Hormone treatments for impotenceIn a small number of men, blood tests may show abnormally low levels of testosterone, the male sex hormone. In such cases your doctor might prescribe a course of testosterone injections or a testosterone implant. The supplements can help boost sex drive as well as increasing the ability to have erections. Testosterone gel or patches, applied daily to the skin, are another option.Complementary medicines for erectile dysfunctionThere is a lack of scientific evidence supporting the effectiveness of complementary therapies for the treatment of impotence.Always check with your doctor before taking any herbal medicines or supplements for impotence. These formulations may contain ingredients that can interact with other medicines or cause dangerous side effects.Counselling for men with impotenceErectile dysfunction often has physical causes, but sometimes there is a psychological basis for erection problems. Often this is a form of performance anxiety. A man may have had an episode of erectile dysfunction due to some passing cause like fatigue, stress, relationship difficulty or intoxication. This may have led to embarrassment or a feeling of failure. Even if the physical cause does not remain, future attempts to have sex may trigger memories of this embarrassment and acute anxiety that it will happen again. This anxiety itself is capable of causing erectile dysfunction, and so a man may get trapped in a self-reinforcing cycle of anxiety and erectile dysfunction. In these instances, seeing a GP, counsellor or psychologist can be very helpful.Stress, anxiety, depression and low self-esteem, in fact, almost all significant emotional problems, can have a major effect on sexuality. So do many chronic physical illnesses, even if they don't directly affect genital function. Counsellors and psychologists can assist with these and a wide range of other sexual and relationship problems and can also help female partners suffering from sexual problems. They are particularly skilled in helping patients to overcome guilt or anxiety relating to sexual abuse, and in helping couples to sort out relationship difficulties. Simple problems can be dealt with in a few visits, but more complex problems may require several months or even years of therapy.Your doctor may be able to recommend a psychologist or counsellor who specialises in sexual and relationship problems. Last Reviewed: 12 December 2016
It appears that testosterone has NOS-independent pathways as well. In one study, castrated rats were implanted with testosterone pellets and then divided into a group that received an NOS inhibitor (L-nitro-L-arginine methyl ester [L-NAME]) and a control group that received no enzyme.  The castrated rats that were given testosterone pellets and L-NAME still had partial erections, a result suggesting the presence of a pathway independent of NOS activity.
L-arginine, an amino acid that is naturally present in the body and helps make nitric oxide, supports a successful erection. Nitric oxide is responsible for making the blood vessels relax, which helps sustain an erection for men. A 1999 study, observed the effects of six weeks of high-dose (5 grams/day) orally administered nitric oxide (NO) donor L-arginine on men with organic ED. Thirty-one percent of those who took 5 grams/day of L-arginine experienced significant improvements in sexual function. Burns told Medical Daily, “l-arginine and deer antler velvet” have been the most popular go-to natural treatments for men.
PDE5i use in PD has not been well studied; however its benefits have been shown. Raffaele performed an open label, prospective study evaluating the efficacy of sildenafil 50 mg on demand and depressive symptoms experienced by the PD patient (73). Erections were improved in approximately 85% of men and 75% noted improvements in their depressive symptoms as well. Sildenafil was well tolerated without significant side effects. Zesiewicz et al., performed a shorter study showing improvements in erectile function but no change in depression and parkinsonisms after ED treatment (74).
Erectile dysfunction in younger men, unless they're diabetic or have suffered some unusually cruel injury, is generally caused by stress, rather than any physical condition. High levels of cortisol or adrenaline (both byproducts of stress) in the body stymie the supply of oxygen to the organs, thereby decreasing blood flow to the penis. And the penis without blood has as much chance of getting up as a balloon without air. Which is why I found it easier to have sex with people I wasn't emotionally invested in: Once the fear of rejection is removed, sex is no big deal.
To find studies on the link between meditation and erectile dysfunction (ED) you have to go way back. A 1977 study by Gerard V Sunnen at New York University on nine men with a mean age of 32 found that as little as two 15 minute sessions of meditation a day transformed the men so that all but two of them could achieve "erectile competence." The study worked by training the men how to deflect negative thought patterns from their mind through meditation.
The medications are extremely effective, which is very good. And the medications are, for the most part, extremely well-tolerated. But there are, like with any medications, a potential downside. The one absolute downside to the use of any of these erection what we call PDE5 medications is if a patient is using a nitroglycerin medication. And nitroglycerins are used for heart disease and for angina, for the most part, although there are some recreational uses of nitrites. And that’s important because your blood vessels will dilate and your blood pressure will drop. And that is an absolute contraindication.
What happens is that the blood vessels of the penis are rather small, and a small amount of plaque in the penile arteries is going to result in erectile dysfunction. You need more plaque before the person’s actually symptomatic from a heart problem, but they’re linked. And so when anybody, any man has an erectile issue, it’s incumbent upon the physician to make certain that their cardiac status is healthy.
The art of acupuncture has become the new treatment for everything from back pain, depression, and even ED. Impotence could be more of a state of mind, and acupuncture may help. Through this alternative therapy, fine needles are placed in various parts of the body to relieve pain or stress. Although there are many mixed studies for acupuncture and ED, many tend to confirm positive results. A 1999 study found acupuncture improved the quality of erection and even restored sexual activity in 39 percent of participants.
If a trial of oral therapy and withdrawal of offending medications do not restore erectile function or if a patient has medical or financial contraindications to pharmacologic therapy, most primary care practitioners should consider referring the patient to a specialist for additional evaluation and discussion of alternative treatment options. However, some primary care practitioners may recommend vacuum constriction devices.
The device consists of an acrylic cylinder placed over the penis that uses a lubricant to achieve a good seal between the penile body and cylinder. An erection is then achieved by creating a vacuum inside the cylinder with a pump connected to the cylinder. Once an erection is achieved, a constriction band is applied to the base of the penis to maintain the erection. The cylinder can then be removed and the patient can engage in intercourse with the constriction band at the base of the penis maintaining the erection. The band can remain on for approximately 30 minutes and then must be removed. The erection produced by the device differs from a normal erection likely because of venous occlusion from the constriction band resulting in generalized swelling of the entire penis, with probable preservation of arterial inflow.
You have to desensitize yourself to stimulation. One way to do this is to masturbate about an hour beforehand, achieving another orgasm shortly after that will be more difficult. If you continue to have trouble, talk to your partner about changes to the timing of your sexual routine, you may need to give them oral or manual stimulation first or after you ejaculate, etc.
Hormone deficiency or hypogonadism, whether primary or secondary, has been thought to impact erectile function. Approximately a third of men in the European Male Aging Study demonstrated low testosterone, suggesting that hypogonadism is overrepresented among men with ED.11 Hormone deficiency, however, is less frequently the cause of ED than diabetes or vascular disease. Many entities with a strong relationship to ED also diminish bioavailable testosterone, including obesity, diabetes, and opioid use. Other hormones involved in testosterone metabolism or availability, like thyroid stimulating hormone and gonadotropins, also may impact erectile quality, presumably through regulating bioavailable testosterone. Understanding the relationship between testosterone and ED has been impaired by a lack of standardized measurement of this hormone and the cyclic nature of its release and consumption.
Factors that mediate contraction in the penis include noradrenaline, endothelin-1, neuropeptide Y, prostanoids, angiotensin II, and others not yet identified. Factors that mediate relaxation include acetylcholine, nitric oxide (NO), vasoactive intestinal polypeptide, pituitary adenylyl cyclase–activating peptide, calcitonin gene–related peptide, adrenomedullin, adenosine triphosphate, and adenosine prostanoids.
Of the drugs used for depression, tricyclic antidepressants may be associated with erectile problems and other drugs may be substituted to prevent this complication. Currently available substitutes include bupropion, nefazodone, and trazodone. The selective serotonin reuptake inhibitors (eg, fluoxetine, sertraline, paroxetine, citalopram) can also cause difficulties with ED, but they might also have other significant sexual side effects, including decreased libido and anorgasmia.
Sexual functioning involves a complex interaction among biologic, sociocultural, and psychological factors, and the complexity of this interaction makes it difficult to ascertain the clinical etiology of sexual dysfunction. Before any diagnosis of sexual dysfunction is made, problems that are explained by a nonsexual mental disorder or other stressors must first be addressed. Thus, in addition to the criteria for erectile disorder, the following must be considered:
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).
In a randomized double-blind, parallel, placebo-controlled trial, sildenafil plus testosterone was not superior to sildenafil plus placebo in improving erectile function in men with ED and low testosterone levels.  The objective of the study was to determine whether the addition of testosterone to sildenafil therapy improves erectile response in men with ED and low testosterone levels.
There have been some studies to suggest that a placebo effect that improves ED may work for some men. One study found that men taking an oral placebo pill showed as much improvement in ED symptoms as men who took actual medication to improve ED. Conversely, men who were given therapeutic suggestions to improve ED did not see signs of symptom improvement.
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
If it is determined that ED is a problem, the patient evaluation should include a detailed sexual and medical history and a physical exam. In particular, it is important to evaluate the ED within the context of ejaculatory problems. There is a strong interplay between premature ejaculation (PE) and ED, with about a third of ED patients reporting PE. The relationship between the PE and ED is bidirectional and successful treatment of one often requires treatment of the other.14
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.
Neurogenic erectile dysfunction (NED) is a traditional classification of erectile dysfunction (ED) encompassing disorders impairing erections via neurologic compromise or dysfunction. The disorders compromising erections may act centrally, peripherally or both. The prevalence of neurogenic ED has been suspected to be between 10% and 19% of all causes of ED (1,2). However, several classically defined neurogenic processes may affect several components of the normal pathway to achieve erection e.g., multiple sclerosis (MS), diabetes mellitus, iatrogenic surgical and spinal cord injury. Each disease state has its own unique characteristics that require acknowledgement to fully understand their effect on ED.
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.
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.
Treatment depends on the underlying cause. In general, exercise, particularly of the aerobic type, is effective for preventing ED during midlife. Exercise as a treatment is under investigation.:6, 18–19 For tobacco smokers, cessation often results in a significant improvement. Oral pharmacotherapy and vacuum erection devices are first-line treatments,:20, 24 followed by injections of drugs into the penis, as well as penile implants.:25–26 Vascular reconstructive surgeries are beneficial in certain groups.
Patients at high cardiovascular risk should not be treated for ED until their cardiac condition is stabilize. These conditions include unstable or refractory angina, myocardial infarction or cerebrovascular accident within the past 2 weeks, uncontrolled hypertension, New York Heart Association (NYHA) Functional Classification III-IV congestive heart failure, high-risk arrhythmias, hypertrophic obstructive cardiomyopathies, and moderate-to-severe valvular disease.25 This class of drugs is also contraindicated in patients who use nitroglycerin or nitrate-containing compounds.26, 27
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A physical cause can be identified in about 80% of cases. These include cardiovascular disease, diabetes mellitus, neurological problems such as following prostatectomy, hypogonadism, and drug side effects. Psychological impotence is where erection or penetration fails due to thoughts or feelings; this is somewhat less frequent, in the order of about 10% of cases. In psychological impotence, there is a strong response to placebo treatment.
Other factors leading to erectile dysfunction are diabetes mellitus, which is a well-known cause of neuropathy). ED is also related to generally poor physical health, poor dietary habits, obesity, and most specifically cardiovascular disease, such as coronary artery disease and peripheral vascular disease. Screening for cardiovascular risk factors, such as smoking, dyslipidemia, hypertension, and alcoholism is helpful.
Both ED and low testosterone (hypogonadism) increase with age. The incidence of the latter is 40% in men aged 45 years and older.  Testosterone is known to be important in mood, cognition, vitality, bone health, and muscle and fat composition. It also plays a key role in sexual dysfunction (eg, low libido, poor erection quality, ejaculatory or orgasmic dysfunction, reduced spontaneous erections, or reduced sexual activity). 
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. 
In rare cases, the drug Viagra ® can cause blue-green shading to vision that lasts for a short time. In rare cases, the drug Cialis® can cause or increase back pain or aching muscles in the back. In most cases, the side effects are linked to PDE5 inhibitor effects on other tissues in the body, meaning they are working to increase blood flow to your penis and at the same time impacting other vascular tissues in your body. These are not ‘allergic reactions'.