It is normal for a man to have five to six erections during sleep, especially during rapid eye movement (REM). Their absence may indicate a problem with nerve function or blood supply in the penis. There are two methods for measuring changes in penile rigidity and circumference during nocturnal erection: snap gauge and strain gauge. A significant proportion of men who have no sexual dysfunction nonetheless do not have regular nocturnal erections.
There have been rare reports of priapism (prolonged and painful erections lasting more than six hours) with the use of PDE5 inhibitors such as sildenafil, vardenafil, and tadalafil. Patients with blood cell diseases such as sickle cell anemia, leukemia, and multiple myeloma have higher than normal risks of developing priapism. Untreated priapism can cause injury to the penis and lead to permanent impotence. Therefore, if your erection lasts four hours, you should seek emergency medical care.
The patient and partner must be well informed about all therapeutic options including their effectiveness, possible complications, and costs. As a general rule, the least invasive or dangerous procedures should be tried first. Psychotherapy and behavioral treatments and sexual counseling alone or in conjunction with other treatments may be used in all patients with erectile dysfunction who are willing to use this form of treatment. In patients in whom psychogenic erectile dysfunction is suspected, sexual counseling should be offered first. Invasive therapy should not be the primary treatment of choice. If history, physical, and screening endocrine evaluations are normal and nonpsychogenic erectile dysfunction is suspected, either vacuum devices or intracavernosal injection therapy can be offered after discussion with the patient and his partner. These latter two therapies may also be useful when combined with psychotherapy in those with psychogenic erectile dysfunction in whom psychotherapy alone has failed. Since further diagnostic testing does not reliably establish specific diagnoses or predict outcomes of therapy, vacuum devices or intracavernosal injections often are applied to a broad spectrum of etiologies of male erectile dysfunction.
If you're regularly having trouble getting or maintaining erection and it's not situation specific (for instance, this happens whether you're with a partner or alone or watching porn or whatever), it could be a tip-off to a physiological problem. Diabetes, high cholesterol, high blood pressure, and cardiovascular issues can all present with erectile problems, says Paduch. That's because basically anything affecting your nerves or blood flow can impact your boners.
PDE 5 inhibitors are broken down primarily by enzyme, cytochrome P450enzyme CYP3A4. Medications that decrease or increase the activity of CYP3A4 may affect levels and effectiveness of PDE 5 inhibitors. Such drugs include medications for the treatment of HIV (protease inhibitors) and the antifungal medications ketoconazole and itraconazole. Thus caution is recommended.
Surgery of the penile venous system, generally involving venous ligation, has been reported to be effective in patients who have been demonstrated to have venous leakage. However, the tests necessary to establish this diagnosis have been incompletely validated; therefore, it is difficult to select patients who will have a predictably good outcome. Moreover, decreased effectiveness of this approach has been reported as longer term followups have been obtained. This has tempered enthusiasm for these procedures, which are probably therefore best done in an investigational setting in medical centers by surgeons experienced in these procedures and their evaluation.
When stimulated by the nerves, the spongy tissue arranges itself in such a way that more blood can be stored in the penis. The veins running through the outer sheath of the penis then compress which stops the blood from leaving the penis. As the blood is stopped from flowing out, the penis fills with blood and stretches within the outer casing, giving an erection.
The first stem cell study for the treatment of ED was published in 2004. This study used embryonic stem cells to treat ED. At this time, there is a total of 36 published basic studies assessing stem cell therapy for ED, with two clinical trials. The mechanism of action of stem cells is to generate angiogenesis with subsequent increase in cavernosal smooth muscle cells within the corporal bodies.46
The male erectile response is a vascular event initiated by neuronal action and maintained by a complex interplay between vascular and neurological events. In its most common form, it is initiated by a central nervous system event that integrates psychogenic stimuli (perception, desire, etc.) and controls the sympathetic and parasympathetic innervation of the penis. Sensory stimuli from the penis are important in continuing this process and in initiating a reflex arc that may cause erection under proper circumstances and may help to maintain erection during sexual activity.
Kimberly Hildebrant, ARNP is a board certified Family Nurse practitioner. She graduated with a Bachelor of Science in Nursing from the University of Pittsburgh and a Masters in Nursing from Duquesne University. She has practiced as a nurse practitioner in the field of Infectious Disease as well as HIV for 4 years. She has over 13 years of experience as a critical care nurse. Kimberly is passionate about providing affordable healthcare to all individuals to ensure that all can live their best life. She is an advocate for preventative care and early treatment to avoid lasting illness.
Erection is a vascular event. The penis becomes rigid when blood flow to the corpora cavernosa increases sixfold and venous outflow is physiologically impeded. Penile perfusion is governed by three organ systems—the neurologic, circulatory, and endocrinologic systems—each necessary for potency. The neurologic system accounts for vasodilation and venoconstriction of the corporal blood vessels so that blood is shunted to the erectile tissues; the circulatory system provides adequate blood flow to the hypogastric-cavernous bed, a distal branch off the internal iliac vessels; and the endocrine system, mediated by testosterone, plays a permissive role through mechanisms that have yet to be elucidated.
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. 
Patients should continue testosterone therapy only if there is improvement in the symptoms of hypogonadism and should be monitored regularly. You will need periodic blood tests for testosterone levels and blood tests to monitor your blood count and PSA. Testosterone therapy has health risks, and thus doctors should closely monitor its use. Testosterone therapy can worsen sleep apnea and congestive heart failure.
The cost to you for ED drug therapy varies considerably, depending on the pharmacy price, prescription co-pays, and your level of health plan coverage. Nationally, the out-of-pocket cost per pill ranges from approximately $15 to $20. Even if private insurance covers it, you may be limited to four doses per month. Here are a few things you can do to contain costs:
The U.S. FDA (Food and Drug Administration) has a list of 29 OTC products that claim to treat erectile dysfunction. Patients should avoid these because many contain harmful ingredients. Other natural or herbal remedies such as DHEA, L-arginine, ginseng, and yohimbe are supplements that have been used but have not been proven safe and effective according to some researchers. Before using such compounds, individuals should consult their doctor. According to some experts, acupuncture does not effectively treat erectile dysfunction. Other home remedies for reducing ED symptoms include diet changes such as eating blueberries and citrus fruits and drinking red wine.
"Data shows the longer you ride, the higher your chance of developing ED in terms of distance per week," Gittens says. If you cycle for exercise or socialization, you don't have to necessarily give it up, just make some modifications. Gittens suggests riding for shorter distances, giving yourself a rest every once in a while, finding a comfortable seat, and getting a bike that’s sized appropriately.
In some cases, ED can be a warning sign of more serious disease. One study suggests ED is a strong predictor of heart attack, stroke, and death from cardiovascular disease. The researchers say all men diagnosed with ED should be evaluated for cardiovascular disease. This does not mean every man with ED will develop heart disease, or that every man with heart disease has ED, but patients should be aware of the link.