Psychological processes such as depression, anxiety, and relationship problems can impair erectile functioning by reducing erotic focus or otherwise reducing awareness of sensory experience. This may lead to inability to initiate or maintain an erection. Etiologic factors for erectile disorders may be categorized as neurogenic, vasculogenic, or psychogenic, but they most commonly appear to derive from problems in all three areas acting in concert.
Davis Liu, MD is a board certified family physician, patient advocate, physician leader, blogger, and the author of two books, including The Thrifty Patient – Vital Insider Tips for Saving Money and Staying Healthy. He’s passionate about making healthcare more convenient, personalized, and affordable. Prior to joining, Dr. Liu was a practicing primary-care doctor for fifteen years at Kaiser Permanente in Roseville, California. He also served on the Permanente Medical Group (TPMG) Board of Directors as Vice Chair of the Finance and Audit committee and the Governance committee. Dr. Liu graduated summa cum laude and Phi Beta Kappa from the Wharton School of Business at the University of Pennsylvania. He received his medical degree from the University of Connecticut School of Medicine.
Defined as experiencing difficulty having an erection at least 50 percent of the time, about 30 million men in the U.S. suffer from erectile dysfunction (ED), according to the National Institutes of Health. So, if odds are pretty good you’ll experience a failure to launch at some point in your life, take solace in this finding from the University of Adelaide: You can reverse ED by focusing on lifestyle factors, not just popping a blue pill.
The risk of impotence increases with age. It is four-fold higher in men in their 60s compared with those in their 40s according to a study published in the Journal of Urology (2000;163:460-463). Men with less education are also more likely to experience impotence, perhaps because they tend to have less healthy lifestyles, eat a less healthy diet, drink more and exercise less. Physical exercise tends to lessen the risk of impotence.
Erectile dysfunction (ED) affects 50% of men older than 40 years,  exerting substantial effects on quality of life.  This common problem is complex and involves multiple pathways. Penile erections are produced by an integration of physiologic processes involving the central nervous, peripheral nervous, hormonal, and vascular systems. Any abnormality in these systems, whether from medication or disease, has a significant impact on the ability to develop and sustain an erection, ejaculate, and experience orgasm.
The drugs are worth trying, but don’t expect miracles. Everyone has heard of Viagra, but Cialis is actually more popular because it’s effective longer—24 to 36 hours instead of three to five. Erection drugs improve erections in around two-thirds of men. They don’t work for about one-third. When they work, they do not produce porn-star erections. Over time, many men need larger doses. But as dosage increases, side effects become more likely, notably, headache and nasal congestion. Finally, the drugs have no effect on arousal, so men may raise erections but don't feel particularly interested in sex. Many men feel disappointed with the drugs. Fewer than half refill their prescriptions.
Sexual dysfunction is highly prevalent in men and women. In the MMAS, 52% of the respondents reported some degree of erectile difficulty. Complete ED, defined as (1) the total inability to obtain or maintain an erection during sexual stimulation and (2) the absence of nocturnal erections, occurred in 10% of the respondents. Mild and moderate ED occurred in 17% and 25% of responders, respectively. 
That means that as an adult, you need to activate the opposing parasympathetic system through sexually exciting visuals, thoughts and touches to get an erection going. But this nerve transmission is disrupted if you're stressed, anxious or distracted. The latter because you simply don't develop enough total stimulation of your genitals to get an erection, and the former because stress and anxiety all increase adrenaline – a key transmitter in the inhibiting sympathetic nervous system. They quite literally sabotage your erection.
Patient can inject medications directly into the corpora cavernosa to help attain and maintain erections. Medications such as papaverine hydrochloride, phentolamine, and prostaglandin E1 (alprostadil) can be used alone or in combinations to attain erections. All of these medications are vasodilators and work by increasing blood flow into the penis. Prostaglandin E1 (Caverject, Edex) is easier to obtain; however, it is associated with penile pain in some individuals. The use of combinations of two or three of these medications can decrease the risk of having penile pain.
In prescribing sildenafil, a doctor considers the age, general health status, and other medication(s) the patient is taking. The usual starting dose for most men is 50 mg, however, the doctor may increase or decrease the dose depending on side effects and effectiveness. The maximum recommended dose is 100 mg every 24 hours. However, many men will need 100 mg of sildenafil for optimal effectiveness, and some doctors are recommending 100 mg as the starting dose.
To a significant degree, the public, particularly older men, is conditioned to accept erectile dysfunction as a condition of progressive aging for which little can be done. In addition, there is considerable inaccurate public information regarding sexual function and dysfunction. Often, this is in the form of advertisements in which enticing promises are made, and patients then become even more demoralized when promised benefits fail to materialize. Accurate information on sexual function and the management of dysfunction must be provided to affected men and their partners. They also must be encouraged to seek professional help, and providers must be aware of the embarrassment and/or discouragement that may often be reasons why men with erectile dysfunction avoid seeking appropriate treatment.
*all photos are models and not actual patients.If you are interested in a prescription product, Hims will assist in setting up a visit for you with an independent physician who will evaluate whether or not you are an appropriate candidate for the prescription product and if appropriate, may write you a prescription for the product which you can fill at the pharmacy of your choice.
Vacuum devices for ED, also called pumps, offer an alternative to medication. The penis is placed inside a cylinder. A pump draws air out of the cylinder, creating a partial vacuum around the penis. This causes it to fill with blood, leading to an erection. An elastic band worn around the base of the penis maintains the erection during intercourse.