Associated morbidity may include various other male sexual dysfunctions, such as premature (early) ejaculation and male hypoactive sexual desire disorder. The NHSLS found that 28.5% of men aged 18-59 years reported premature ejaculation, and 15.8% lacked sexual interest during the past year. An additional 17% reported anxiety about sexual performance, and 8.1% had a lack of pleasure in sex. 
The mechanisms by which testosterone plays a role in erectile function are not completely understood. A study evaluating the effect of testosterone on erections in surgically castrated rabbits and control animals, in which the rabbits’ intracavernosal pressures were compared after cavernosal nerve stimulation, determined that castrated rabbits had much lower pressures after stimulation than control rabbits did.  Notably, the pressures increased when castrated rabbits received exogenous testosterone replacement.
Penile injection therapy, intracavernous injection, involves the injection of a vasodilator (a chemical that relaxes arteries to increase blood flow) into the penis. Penile injected therapy is recognized as the most effective nonsurgical treatment for erectile dysfunction. However, due to the invasive nature, it is often used in men who have failed or have contraindications to other treatments such as oral therapies.
Counselling or sex therapy (58% of people find this works for them) –mind-related causes of erectile dysfunction can affect anyone. They are more likely if you experience erectile dysfunction at a younger age. Talking to a counsellor or therapist can help some people overcome erectile dysfunction related to these problems, possibly for good. They can also help you if your erectile dysfunction is causing you stress, as this can make matters worse.
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.
Once a complete sexual and medical history has been completed, appropriate laboratory studies should be conducted. In the initial evaluation of ED, sophisticated laboratory testing is rarely necessary. For example, serum testosterone (and sometimes prolactin) is typically only useful when the patient demonstrates hypogonadal features or testicular atrophy, or when clinical history is suggestive. Additional hormonal evaluation may include thyroid stimulating hormone in those with a clinical suspicion of hypothyroidism or appropriate diabetes screening in those presenting with a concern for impaired glucose metabolism. If the patient has not been evaluated with a lipid panel and hyperlipidemia is suspected, measurement and appropriate referral to internal medicine or cardiology is recommended. In most cases, a tentative diagnosis can be established with a complete sexual and medical history, physical examination, and limited or no laboratory testing.
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.  This study suggests that a certain level of testosterone may be necessary for PDE5 inhibitors to function properly.
The Latin term impotentia coeundi describes simple inability to insert the penis into the vagina; it is now mostly replaced by more precise terms, such as erectile dysfunction (ED). The study of ED within medicine is covered by andrology, a sub-field within urology. Research indicates that ED is common, and it is suggested that approximately 40% of males experience symptoms compatible with ED, at least occasionally. The condition is also on occasion called phallic impotence. Its antonym, or opposite condition, is priapism.
There are also alternative treatments, such as using a penis pump or a penile injection. Penis pumps work by creating a vacuum and thereby causing more blood to flow to your penis. Penile injections need to be used shortly before intercourse. They contain a medication which widens your blood vessels. A doctor’s prescription is needed for the injections.
Before taking any medication for erectile dysfunction, including over-the-counter supplements and herbal remedies, get your doctor's OK. Medications for erectile dysfunction do not work in all men and might be less effective in certain conditions, such as after prostate surgery or if you have diabetes. Some medications might also be dangerous if you:
Examples of common neurologic conditions that can lead to ED include cerebral vascular accident, multiple sclerosis, Parkinson’s disease, and spinal cord injury. Microvascular disease associated with diabetes is thought to compound the endothelial and neural injuries associated with this disease. Pelvic surgery may disrupt both neural and vascular pathways, resulting in ED.
This isn’t all that surprising. When you feel blue and low on energy, it can be extremely difficult to perform at your sexual peak. Furthermore, depression is linked to changes in your brain chemistry and nervous system. Some of these areas also affect your sex drive and ability to have an erection. This means that depression can change the way your brain works, making ED more likely.
Cialis is available in three strengths: 5mg, 10 mg, and 20 mg. Cialis can work in 30 minutes, but peak results usually take longer. Cialis has the advantage of a much longer period (24-36 hours) during which sexual ability is increased. The newest formulation of Cialis is the 5 mg dosage for daily use. The major advantage of daily dosing is that it allows for spontaneous sexual activity.
In order to establish whether normal erections are occurring overnight (nocturnal erections), the doctor may organise nocturnal penile tumescence (NPT) testing. This involves wearing a monitor overnight in your own home. The data from this monitor is then assessed to analyse how often erections occurred, how long they lasted, and how rigid and large the penis was during the erections. If NPT testing is normal, the cause of erectile dysfunction is usually psychological. If not, further testing of the blood flow in the genital area may be required to see if there is blockage or leakage. The doctor may also organise a blood test of levels of hormones such as testosterone, prolactin and thyroid stimulating hormone to see if these are contributing to the erectile dysfunction.
The Prostate Cancer Prevention Trial was a landmark study by Thompson et al that prospectively assessed the time to developing CVD after the diagnosis of ED. There were 4247 men with no ED at study entry; 2420 developed incident ED (defined as the first report of ED of any grade) over 5 years. Those men that developed ED had a 1.45-fold higher probability of experiencing a CV event compared with men who did not develop ED.27
Ultimately, PDE5i have had a significant impact on the treatment of ED in men with SCI. The ease of use and tolerability of the medication has also led to improved satisfaction and quality of life that had been previously affected by SD. Head to head trials evaluating specific PDE5i within the SCI population are required to further elucidate drug preference. PDE5i should be considered first line therapy, however men with high thoracic and cervical lesions should be warned about an increased chance of dizziness with sildenafil and possibly other PDE5i use.
Watts and coworkers, in their review article, make several points about this ED/CAD nexus. Endothelial dysfunction is present in both CVD and ED, and is linked through the NO mechanism. The authors note that PDE5 inhibitors improve endothelial function and have a salutary effect on both CVD and ED. Both ED and cardiac disease respond to modifications in lifestyle as well as pharmacologic manipulation. These authors also report that the presence of ED gives the clinician an opportunity to assess CVD and prevention as well.20
Finally, there are NO-releasing polymers that are capable of delivering NO in a pharmacologically useful way. Such compounds include compounds that release NO upon being metabolised and compounds that release NO spontaneously in aqueous solution. Initial animal studies suggest that cavernosal injections of NO polymers can significantly improve erectile function.48
Erectile dysfunction or disorder (ED) is the inability to develop and maintain an erection for satisfactory sexual intercourse or activity. Erectile dysfunction or erectile disorder are the preferred terms as opposed to impotence. There are no uniform criteria defining how consistent the problem has to be and for what duration it must be present to considered ED. The Diagnostic and Statistical Manual of Mental Disorder-5 specifies a duration of at least 6 months in its definition of ED.1
Physical causes may include the narrowing of the blood vessels caused by hypertension (high blood pressure), nutritional deficiencies, certain prescription treatments and medications for enlarged prostate or prostate cancer, excess drinking, obesity, heavy smoking, kidney issues, thyroid problems, hormonal changes due to aging, injury, or surgery, diabetes, and high cholesterol levels.
Given the high risk of priapism during escalation of therapy for intracorporeal injection, it is recommended that the drugs be administered in a supervised office visit initially and that the patient be given a well-articulated plan for treatment of priapism if it occurs. Escalation guidelines for alprostadil alone vary, but a general guideline is to start at 2.5 mcg and increase by 2.5 mcg to a dose of 5 mcg and then in increments of 5 mcg to 10 mcg until an erection sufficient for penetration, not lasting more than 1 hour, is achieved. If there is no response to the initial 2.5-mcg dose, escalation dosing can be slightly more liberal.34 A European prospective trial of PGE1 alone found 91% of the 54 patients completing the 4 years of the study reported good or better tolerability and satisfaction with therapy.35
3. Testosterone replacement. Before oral medications like Viagra, testosterone was routinely used to treat erectile dysfunction as it is central in the male sexual response, including the desire for sex and the process of getting an erection. Testosterone can be administered in a number of ways, for example orally, by means of an injection, skin patch, or subcutaneous (under the skin) pellet.
All devices that are currently approved by the FDA are considered safe for use in magnetic resonance imaging environments. However, 2 previously approved devices–the OmniPhase and the DuraPhase penile prostheses–are not considered safe in this environment. Other surgical procedures–including venous ligation to limit penile venous outflow and penile revascularization procedures–are rarely successful and are not recommended.19 These surgeries are only indicated when a patient demonstrates recent-onset ED and an occlusive lesion seen on angiogram or magnetic resonance angiography and should be performed only in centers of excellence for ED.
In the short term, alcohol relaxes muscles in the penis, letting blood to flow in (which is a good thing). However, alcohol also prevents other blood vessels from closing and trapping all the extra blood. Erections depend on trapping increased blood flow in the erectile tissue of the penis. If you don’t trap that extra blood, you don’t get an erection. In the long run, excessive alcohol consumption can cause liver scarring, high blood pressure, and can damage your blood vessels resulting in erectile dysfunction.