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.
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 is often the result of atherosclerosis, and as a result, men with ED frequently have cardiovascular disease. Sexual activity is associated with increased physical exertion, which in some men may increase the risk of having a heart attack (myocardial infarction or MI). The major risk factors associated with cardiovascular disease are age, hypertension, diabetes mellitus, obesity, smoking, abnormal lipid/cholesterol levels in the blood, and lack of exercise. Individuals with three or more of these risk factors are at increased risk for a heart attack during sexual activity. The Princeton Consensus Panel developed guidelines for treating ED in men with cardiovascular disease. Thus, if you have ED and cardiovascular disease (for example, angina or prior heart attack), you should discuss whether or not treatment of ED and sexual activity are appropriate for you.
#4 You’re just plain turned off. It happens. Whether it’s the weight your partner has put on, the realization that you’re having period sex, or you’re just not getting what you need in the bedroom, at some point in your life, you’re going to be turned off enough to lose *or be unable to attain* your hard-on. [Read: Not attracted to your girlfriend anymore? The why and the fixes]
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.
Uncooperative boners might be related to low testosterone, which could be caused by anything from being overweight or stressed to having a chronic health condition, says Paduch. And in men who have taken anabolic steroids, it's not uncommon for them to end up suppressing their natural testosterone production. If you abuse it over a long period of time, you can really mess with your natural testosterone levels, as well as your fertility and erectile function, he says.
Radical prostatectomy for the treatment of prostate cancer poses a significant risk of ED. A number of factors are associated with the chance of preserving erectile function. If both nerves that course on the lateral edges of the prostate can be saved, the chance of maintaining erectile function is reasonable. The odds depend on the age of the patient. Men younger than 60 years have a 75-80% chance of preserving potency, but men older than 70 years have only a 10-15% chance.
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.
In the meantime, make sure he gets some rest and takes it easy. The more you two stress about it — and the more pressure he feels you are putting on him — the harder it will get for him to get hard, in all likelihood. So take a few days off. Relax, be patient, and help him find him some help if he needs it. In the meantime, here's a Cosmopolitan.com guide about exactly this topic from sex therapist Dr. Jane Greer.
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).  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. 
Vijay Bhat, MD is a board certified internal medicine physician who is passionate about providing quality medical care that’s affordable for patients. He believes that integrating technology and medicine can make healthcare efficient and more accessible. Throughout his training Dr. Bhat was involved with global health initiatives, providing care to underprivileged communities locally and overseas. He’s also been a strong proponent of quality improvement in the medical field. Dr. Bhat graduated with a BS from the University of California Berkeley, and received his medical degree from Stony Brook University in New York. He completed his residency in Internal Medicine at Rutgers Robert Wood Johnson.
The history can be useful in distinguishing organic from psychogenic impotence (Table 187.1). The patient with organic impotence describes problems with erection that progress over months to years. At first, the patient will have partial erections or seemingly firm erections that become flaccid during intercourse. With time, total erectile failure ensues. Organic impotence is constant and nonselective, meaning it is not better or worse with any specific partner or any type of stimulation.
Estimates of the prevalence of impotence depend on the definition employed for this condition. For the purposes of this consensus development conference statement, impotence is defined as male erectile dysfunction, that is, the inability to achieve or maintain an erection sufficient for satisfactory sexual performance. Erectile performance has been characterized by the degree of dysfunction, and estimates of prevalence (the number of men with the condition) vary depending on the definition of erectile dysfunction used.
Causes of impotence are many and include heart disease, high cholesterol, high blood pressure, obesity, metabolic syndrome, Parkinson's disease, Peyronie's disease, substance abuse, sleep disorders, BPH treatments, relationship problems, blood vessel diseases (such as peripheral vascular disease and others), systemic disease, hormonal imbalance, and medications (such as blood pressure and heart medications).
So what can you do to help things along a little? Well, chances are it may sort itself out as you settle in to your relationship. But if it keeps happening and you see a future in the relationship, you need to talk about it, or it will soon become the elephant in the bedroom. Pick a time with no distractions and where nobody can overhear you. Tell them that you care about them and that you don’t need to rush things sexually. This can take the pressure off the need to perform.
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
Modern drug therapy for ED made a significant advance in 1983, when British physiologist Giles Brindley dropped his trousers and demonstrated to a shocked Urodynamics Society audience his papaverine-induced erection. The drug Brindley injected into his penis was a non-specific vasodilator, an alpha-blocking agent, and the mechanism of action was clearly corporal smooth muscle relaxation. The effect that Brindley discovered established the fundamentals for the later development of specific, safe, and orally effective drug therapies.[better source needed][better source needed]
After the history, physical examination, and laboratory testing, a clinical impression can be obtained of a primarily psychogenic, organic, or mixed etiology for erectile dysfunction. Patients with primary or associated psychogenic factors may be offered further psychologic evaluation, and patients with endocrine abnormalities may be referred to an endocrinologist to evaluate the possibility of a pituitary lesion or hypogonadism. Unless previously diagnosed, suspicion of neurologic deficit may be further assessed by complete neurologic evaluation. No further diagnostic tests appear necessary for those patients who favor noninvasive treatment (e.g., vacuum constrictive devices, or pharmacologic injection therapy). Patients who do not respond satisfactorily to these noninvasive treatments may be candidates for penile implant surgery or further diagnostic testing for possible additional invasive therapies.
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.  The hazard ratio was 1.45, which is in the range of risk associated with current smoking or a family history of MI.
While pills for ED are convenient, some men sustain stronger erections by injecting medication directly into the penis. Drugs approved for this purpose work by widening the blood vessels, causing the penis to become engorged with blood. Another option is inserting a medicated pellet into the urethra. The pellet can trigger an erection within 10 minutes.