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Erectile Dysfunction

Erectile dysfunction (impotence) occurs when a man can no longer get or maintain an erection firm enough for sexual intercourse. Having erection trouble from time to time isn't necessarily a cause for concern. But if erectile dysfunction is an ongoing problem, it may cause stress, cause relationship problems or affect your self-confidence.

Even though it may seem awkward to talk with your doctor about erectile dysfunction, go in for an evaluation. Problems getting or keeping an erection can be a sign of a health condition that needs treatment, such as heart disease or poorly controlled diabetes. Treating an underlying problem may be enough to reverse your erectile dysfunction.

If treating an underlying condition doesn't help your erectile dysfunction, medications or other direct treatments may work.

Q&A Erectile Dysfunction

How common is Erectile Dysfunction?

Most men have occasional times when they cannot get an erection. For example, you may not get an erection so easily if you are tired, stressed, distracted, or have drunk too much alcohol. For most men it is only temporary, and an erection occurs most times when you are sexually aroused.

However, some men have persistent, or recurring, ED. It can occur at any age, but becomes more common with increasing age. About half of men between the ages of 50 and 70 have ED. About 7 in 10 men aged 70 and above have ED.

How does an Erection Normally occur?

A man needs hormones, an adequate blood flow to the penis, intact nerves and sexual desire if he is to achieve an erection. If one or more of these mechanisms fail, erection may also fail.

During arousal, nerve impulses travel from the brain to the penis and trigger smooth muscle relaxation in the penis. This encourages blood to flow into the tissues. As the penis fills with blood, it enlarges and becomes erect. During enlargement, the veins in the penis become compressed, blocking the flow of blood out of the penis and, as a result, the erection persists. The penis stays erect until ejaculation is completed or sexual arousal ceases.

What causes Erectile Dysfunction?

Hormone imbalance

A deficiency of male hormones can reduce desire or interest in sexual function.

Nerve damage

This can result in reduced sensitivity or reduced signals to release chemicals within the penis that cause muscle relaxation.

Disease of the blood vessels

Blood vessels often become narrowed and hardened with increasing age. This reduces blood supply to the penis. If the penis does not fill adequately with blood, the veins will not be compressed and blood will leak out of the penis. As a result, the erection will not be maintained.


Trauma, such as injury to the spinal cord.

Pelvic surgery

Some cancer operations on the prostate, bladder or bowel may result in nerve damage leading to impotence.


Some drugs used to treat high blood pressure or depression, and some sedatives may cause impotence.

Smoking and alcohol

Those who smoke and drink are more likely to suffer from impotence. In men with diabetes the most common causes of erectile dysfunction are disease of the blood vessels and nerve damage (or a combination of the two).

Mental heath (psychological) causes

Various mental health conditions may cause you to develop ED. They include:

  • Stress - for example, due to a difficult work or home situation.
  • Anxiety.
  • Relationship difficulties.
  • Depression.

Typically, the ED develops quite suddenly if it is a symptom of a mental health problem. The ED may resolve when your mental state improves - for example, if your anxiety or depression eases. However, some people become even more anxious or depressed when they develop ED. They do not realise it is a reaction to their mental health problem. This can make matters worse and lead to a vicious circle of worsening anxiety and persisting ED.

As a rule, a psychological cause for the ED is more likely than a physical cause if there are times when you can get a good erection, even though most of the time you cannot. (For example, if you can get an erection by masturbating, or wake up in the morning with an erection.)

Erectile Dysfunction, Heart Disease and other Vascular Diseases

Although ED can be caused by various conditions, about 7 in 10 cases are due to narrowing of the small arteries in the penis. This causes reduced blood flow to the penis. This is the same problem that can occur in other blood vessels. For example, narrowing of the blood vessels in the heart (the coronary arteries) is a cause of angina and other heart problems. Narrowing of blood vessels to the brain is a risk factor for having a stroke. Narrowing of blood vessels in the legs can cause peripheral arterial disease. Therefore, even if the erectile dysfunction does not bother you it is advisable to see your GP to for a check up to make sure you are not developing cardiovascular disease.

What should I do if I develop persistent Erectile Dysfunction?

It is best to see your GP. He or she is likely to discuss the problem, go over any medication you may be taking, and do a physical examination. This can help to identify or rule out possible underlying causes. Before treatment, your GP may suggest some tests.

What tests may be done?

Depending on your symptoms, likely cause of the ED, age, etc., your doctor may suggest that you have some tests. These are mainly to check up on any risk factors listed above which increase the risk of developing narrowing of the arteries.

Tests may include:

  • A blood test to check the level of cholesterol and other fats (lipids).
  • Blood sugar level.
  • Blood tests to rule out kidney and liver disease.
  • A urine test.
  • A check of your blood pressure.
  • A heart tracing (ECG).
  • Other heart tests, which are sometimes done where appropriate, if heart disease is suspected.

If you have a low sex drive, or if you have had a previous head injury, ED may be due to a hormonal problem. In this situation a blood test to check the level of the hormone testosterone (and sometimes prolactin) may be advised.

In a small number of cases, tests to check the way the blood circulates through the penis, using scans or drug injections, may be done in hospital clinics.

What are the treatment options?

Oral medication

First-line treatment for most patients is now tablet treatment using Viagra, Levitra or Cialis. Your GP will prescribe the tablets for you in the first instance.

Injection treatment

This was the most common treatment before tablets became available. It usually works very well. You are taught how to inject a medicine into the base of the penis. This causes increased blood flow, and an erection usually develops within 15 minutes. (Unlike with tablets, the erection occurs whether of not you are sexually aroused.)

Vacuum devices

There are several different devices. Basically, you put your penis into a plastic container. A pump then sucks out the air from the container to create a vacuum. This causes blood to be drawn into the penis and cause an erection. When erect, a rubber band is placed at the base of the penis to maintain the erection. The plastic container is then taken off the penis and the penis remains erect until the rubber band is removed (which must be removed within 30 minutes).

Penile prosthesis

A surgeon can insert rods or inflatable cylinders permanently into the penis. The most sophisticated (expensive) type can be inflated with an inbuilt pump to cause an erection. The more basic type keeps the penis rigid all the time.


Some men need psychosexual counselling and will be referred to a specialist in this area. Counselling can be part or all of the treatment required.

Q&A Erectile Dysfunction treatment options