It can also help to tell your partner (either before you start or when it happens) that hey, sometimes it takes your penis a while to warm up or sometimes it comes and goes as it pleases — and that they shouldn't take it personally and you won't let it ruin the moment. When it happens, take a few deep breaths, focus on your partner, and go back to doing whatever was feeling good before. "If they approach that with authentic confidence, the partner is usually like 'OK, cool,'" says Skyler. "Remember, you're more than just your penis."
Tests such as the bulbocavernosus reflex test are used to determine if there is sufficient nerve sensation in the penis. The physician squeezes the glans (head) of the penis, which immediately causes the anus to contract if nerve function is normal. A physician measures the latency between squeeze and contraction by observing the anal sphincter or by feeling it with a gloved finger inserted past the anus.
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.
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.
For example, many men with diabetes mellitus may develop erectile dysfunction during their young and middle adult years. Physicians, diabetes educators, and patients and their families are sometimes unaware of this potential complication. Whatever the causal factors, discomfort of patients and health care providers in discussing sexual issues becomes a barrier to pursuing treatment.
Psychosocial problems are important and may cause erectile dysfunction by themselves or together with other causes of erectile dysfunction, such as diabetes and heart disease. Relationships are complicated and many factors cause tensions, which can affect sexual relations. For some men, these problems can become ongoing and it can help to talk through the issue with a skilled counsellor. It is important to know that the longer erectile dysfunction is left untreated, the greater the effect on relationships. This is another reason why early treatment of erectile dysfunction is important.
The primary nerve fibers to the penis are from the dorsal nerve of the penis, a branch of the pudendal nerve. The cavernosal nerves are a part of the autonomic nervous system and incorporate both sympathetic and parasympathetic fibers. They travel posterolaterally along the prostate and enter the corpora cavernosa and corpus spongiosum to regulate blood flow during erection and detumescence. The dorsal somatic nerves are also branches of the pudendal nerves. They are primarily responsible for penile sensation. 
I’m going to share a secret with you. I understand that for men it’s a big (well, perhaps flaccid and at least momentarily small) deal when you can’t get hard. However, in most instances, women don’t give a fuck. We’re understanding creatures who (ahem) know a thing or two about not being able to get off every time. To ease the awkwardness, here are a few go-to phrases to drop when you just can’t get it up.
If you’re no longer having intercourse, you don’t need erections. Most men assume that erections are necessary for sex. No. Couples can have great sex without them. Intercourse becomes problematic for older couples. Men have erection issues and post-menopausal women develop vaginal dryness and atrophy that can make intercourse uncomfortable (or worse) even with lubricants. Many older couples jettison intercourse in favor of mutual massage, oral sex, and sex toys—and still enjoy hot sex.
There are no formal tests to diagnose erectile dysfunction. Some blood tests are generally done to exclude underlying disease, such as hypogonadism and prolactinoma. Impotence 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. Therefore, a thorough physical examination is helpful, in particular the simple search for a previously undetected groin hernia since it can affect sexual functions in men and is easily curable.
You’ve probably heard of Viagra, but it’s not the only pill for ED. This class of drugs also includes Cialis, Levitra, Staxyn, and Stendra. All work by improving blood flow to the penis during arousal. They're generally taken 30-60 minutes before sexual activity and should not be used more than once a day. Cialis can be taken up to 36 hours before sexual activity and also comes in a lower, daily dose. Staxyn dissolves in the mouth. All require an OK from your doctor first for safety.