What is Erectile Dysfunction?

Male Reproductive Organs
Male Reproductive Organs

Erectile dysfunction, or ED, is when it is hard to get or keep an erection that's firm enough for sex. ED affects as many as 30 million men.

Most men have problems with erections from time to time. But when this happens more than half of the time, then ED is present. ED can happen when health problems limit blood flow or damage nerves in the penis. ED can also be caused by stress or emotional reasons. ED can be an early warning of a more serious illness. Heart disease, high blood pressure and high blood sugar can all cause ED. Finding and treating the cause(s) of your ED can help your overall health and well-being.

How Erections Work

When you are not sexually aroused, your penis is soft and limp. During sexual arousal, nerve messages release chemicals that increase blood flow into the penis. The blood flows into 2 erection chambers made of spongy tissue (the corpus cavernosum) in the penis. The "smooth muscle" in the erection chambers relaxes, which lets blood enter and stay in the chambers. The pressure of the blood in the chambers makes the penis firm, giving you an erection. After you have an orgasm, the blood flows out of the chambers and the erection goes away.

What are the Symptoms of ED?

When you have ED, it is hard to get or keep an erection that is firm enough for sex. Most men have trouble with erections from time to time, but in some men it is a regular and more bothersome problem. ED can cause:

  • Low self-esteem
  • Performance anxiety
  • Depression
  • Stress

ED may affect the quality of a marriage or intimate relationships.

What Causes ED?

ED can result from health or emotional problems or from both. Lower blood flow or harm to nerves in the penis can lead to erection problems.

Physical Causes of ED

Some things that can increase the chances of getting ED (known as risk factors) are:

  • Age over 50
  • High blood sugar (diabetes)
  • High blood pressure
  • High cholesterol
  • Smoking
  • Cardiovascular disease
  • Drug or alcohol abuse
  • Obesity
  • Lack of exercise

Even though ED becomes more common as men age, growing old is not the cause of the problem. ED can be an early sign of a more serious health problem. Finding and treating the cause(s) of your ED can improve your overall health and well-being.

ED may happen because:

  • Not enough blood flows into the penis
    Many health issues can reduce blood flow into the penis, such as heart disease, high blood sugar (diabetes), and smoking.
  • The penis cannot store blood during an erection
    A man with this problem cannot keep an erection because blood does not stay trapped in the penis. This condition can occur in men of any age.
  • Nerve signals from the brain or spinal cord do not reach the penis
    Certain diseases, injury or surgery in the pelvic area can harm nerves in the penis.

Emotional Causes of ED

Sex activity needs the mind and body to work together. Emotional or relationship problems can cause or worsen ED.

Some emotional issues that can cause ED are:

  • Depression
  • Relationship conflicts
  • Stress at home or work
  • Worry about sexual performance

How is ED Diagnosed?

Finding the cause of your ED will help your health care provider find the best treatment choices for you. Most health care providers will ask you about your general health and the history of your erection problem. Your health care provider may also give you a physical exam and order lab tests.

Health and ED History

Your doctor will ask you questions about your health and lifestyle. For example, certain medicines may be helping to cause your ED. Also, smoking or alcohol use can affect erections. Being open with your health providers will allow them to find the best treatment choices for you. It's important to discuss different things that you can do to improve your condition and your health.

What Questions Might My Health Care Provider Ask?

Questions About Health Problems

Some questions you may be asked are:

  • What health problems do you have?
  • What medicines do you take?
  • Do you smoke, drink, or use other drugs? If so, how much?
  • Do you have any prior history of surgery or radiation therapy, especially in the pelvic area?
  • Do you have urinary problems?

Questions About ED

Asking questions about your history of ED can help your health care provider find out whether your problems are with desire for sex, erection, ejaculation, or orgasm (climax). Some of these questions will be personal and may seem embarrassing. Honest answers will help find the cause and best treatment for your ED.

Some questions about your ED that you may be asked are:

  • How long have you had these symptoms? Did they start slowly or all at once?
  • Do you wake up in the morning with an erection? Do you wake up during the night with an erection?
  • If you do have erections, how firm are they? Is penetration difficult?
  • Do your erections change at different times such as when entering a partner, during stimulation by mouth or with masturbation?
  • Do you have problems with sex drive, arousal, ejaculation, or orgasm (climax)?
  • How is this problem affecting your enjoyment of sex?
  • What effect is this problem having on your relationship (if you are in one)?

Questions About Stress and Emotional Health

Your health care provider may ask you questions about feelings such as depression or worry. He or she may also ask about problems in your relationship with a partner. Some health care providers may ask if it is okay to talk to your sex partner, also.

Some questions you may be asked about your emotional health are:

  • How is your relationship with your partner? Has anything changed lately?
  • How satisfied are you with your sex life? Has anything changed lately?
  • Are you under a lot of stress most of the time? Or has anything especially upsetting happened to you?
  • Do you have any mental illnesses or depression? Are you taking any meds for depression or anxiety?

Physical Exam

A physical exam checks overall health. This may involve checking your blood pressure, penis and testicles. You may need to have a rectal exam to check your prostate. These tests are not painful and may give useful information about the cause of your ED. Most patients do not need a lot of testing before starting treatment.

Lab Tests

To test for diseases that cause ED, your health care provider may order blood tests and collect a urine sample.

Other Tests

Erectile Function Tests

Your health care provider will test to see how the blood vessels, nerves, muscles and other tissues of your penis and pelvic area are working. Normal nocturnal penile tumescence (NPT), or healthy automatic erections during sleep, shows that your nerves and blood supply are working properly.


A duplex ultrasound shows what's happening inside your body by bouncing sound waves off an organ to form pictures on a monitor. It checks for blood flow, vein leaks, scars on erectile tissue and some signs of clogged arteries. If you take this test, you may be given an injection into your penis to cause an erection. The technician can then see how the blood flow and pressure changes in your penis, as well as how it expands. These images are compared to images of the limp penis.

How is ED Treated?

The treatment for ED depends on what is causing it.

Your health care provider may ask you to change certain habits, stop smoking, or using drugs or alcohol. He or she may suggest treatment for emotional problems, relationship conflicts, depression, or performance anxiety. Or you may be asked to change the way you take other medicines. (Never stop or change any drug without first talking to your health care provider.)

Testosterone Replacement Therapy

If a blood test shows low testosterone levels (low T), testosterone replacement therapy (TRT) may help. However, adding TRT will not help your erection problems if you have normal testosterone levels.


Dietary supplements (often called "herbal remedies") for ED are popular but may not be safe or even work. Unlike prescription drugs, they do not have to be proven to work to be sold. Check with your health care provider before you take any supplements or drugs to treat your ED.

Other Treatments

Most of the best-known treatments for ED work well and are safe. But in making your choice, ask your health care provider about any possible problems that could result with each option:

  • Vacuum erection device
  • Oral drugs
  • Drugs in the penis
  • Surgery

Vacuum Erection Device

Vacuum Erection Device
Vacuum Erection Device
National Institute of Diabetes and Digestive and Kidney Diseases,
National Institutes of Health

A vacuum erection device is a plastic tube that slips over the penis, making a seal with the skin of the body. A pump at the other end of the tube creates a low-pressure vacuum around the erectile tissue, which results in an erection. An elastic ring is then slipped onto the base of the penis. This holds the blood in the penis (and keeps it hard) for up to 30 minutes. With proper training, 75 out of 100 men can get a working erection using a vacuum erection device.

Oral Drugs

Drugs known as PDE-5 inhibitors relax muscle cells in the penis and increase blood flow. (These are the drugs you often see on TV and in Internet ads.)

  • Viagra® (sildenafil citrate)
  • Levitra® (vardenafil HCl)
  • Cialis® (tadalafil)

Men with ED take these pills before having sex. The drugs boost the natural signals that are generated during sex to help you have a better erection that lasts longer. The drug works by relaxing the muscle cells in the penis, letting the blood flow better to give a firm erection. These drugs often work well, and nearly 80 out 100 men show improvement once they start using them.

The side effects of PDE-5 inhibitors are mild and often last just a short time. The side effects also get weaker the longer you use the drug. The most common side effects are:

  • Headache
  • Stuffy nose
  • Flushing
  • Muscle aches

In rare cases, sildenafil can cause blue-green shading of vision that lasts for a short time. There is no long-term risk and the problem goes away as the amount of the drug in the body lowers. It is important to follow the instructions for taking this drug to get the best results.

If you are taking nitrates for your heart, you should speak with your health care provider before using a PDE-5 inhibitor to learn how it might affect your health.

Drugs in the Penis

If oral drugs don't work, another drug, alprostadil, is approved for use in men with ED. This drug comes in two forms, depending on how it is to be used:

Self-Injection Therapy

Medical Injections for Impotence
Medical Injections for Impotence

The drug is injected into the side of penis with a very fine needle. The success rate for getting an erection firm enough to have sex is as high as 85%.

Intraurethral Therapy

Transurethral Therapy for Impotence

Transurethral Therapy for Impotence

A tiny medicated pellet of the drug is placed in the urethra (the tube that carries urine out of your body). Using the drug this way avoids having to give yourself a shot, but makes it less likely to work.

The most common side effects of alprostadil are a burning feeling in the penis, and an erection that can last for over four hours and need medical attention to make it go down.

Surgical Treatment

When other treatments do not improve ED, your health care provider may offer you surgery. Surgeries that help treat ED are penile implant surgery and surgeries to fix problems with blood vessels in the penis. Fixing blood vessels only helps in very specific cases.

Penile Prostheses

Penile implants (also called penile prostheses) are devices that are placed completely inside your body. They produce a stiff penis that lets you have normal sex. Penile implants are a good treatment choice for some men. There are two types of penile implants.

Bendable Implant

The simplest kind of implant consists of 2 easy-to-bend rods that are most often made of silicone. These silicone rods give the man's penis the firmness needed to have sex. The implant can be bent downward for peeing or upward for sex.

Inflatable Implant

Penile Pump Implant - Inflatable
Penile Pump Implant - Inflatable
Image © 2003 Fairman Studios, LLC.

With an inflatable implant, fluid-filled cylinders are placed lengthwise in the penis. Tubing connects these rods to a pump that is placed inside the scrotum (the sac that holds the testicles). When the pump pushes fluid into the cylinders, they make the penis hard. Inflatable implants are the most natural feeling of the penile implants, as they let you control firmness and size.

In the simplest inflatable implants, the pump moves a small amount of fluid into the cylinders for erection then out again when erection is no longer needed. These devices are often called 2-part (or 2-component) penile implants. One part is the paired cylinders and the second part is the scrotal pump.

A 3-part inflatable penile implant has paired cylinders, a scrotal pump, and a fluid reservoir in the belly. With these three-part devices, a larger volume of fluid is pumped into the cylinders for erection and out of the cylinders when erection is no longer needed.

What is the Surgery Like?

Penile implants are usually placed under anesthesia, during a 1-hour surgery. Usually 1 small surgical cut is made either above the penis where it joins the abdomen or under the penis where it joins the scrotum. No tissue is removed, blood loss is small and blood transfusion is almost never needed. A patient will usually spend 1 night in the hospital for observation.

Most men have pain after the surgery for about 4 weeks. During this time, oral pain medicine is needed and you are not allowed to drive. If men limit their physical activity while pain is present, the pain usually ends sooner. Men can often be taught how to use the prosthesis for sex 1 month after surgery, but if there is still pain and soreness this may be delayed for another month.

If there is an infection, or the implant fails to work, it will usually have to be removed. On rare occasions, the device can cause pain or reduced feeling. It is important to know that after an implant is placed, other non-surgical treatments will no longer work if that prosthesis is removed. Fortunately, most men with penile implants and their partners say that they're satisfied with the results.

Penile Arterial Revascularization

Young men (under 45) who have had injuries to the pelvis or penis are most likely to be helped by this treatment. This surgery fixes problems with blocked or injured blood vessels in the penis. It may help in rare cases. It is mostly considered for men with no known risk factors for hardened arteries. When an accident leaves a penile vessel too injured or blocked to carry blood, the surgeon may connect to a nearby artery to get around the site. This can clear a pathway so enough blood can be supplied to the penis to cause an erection.

Venous Ligation Surgery

This procedure binds leaky penile vessels that cause the penis to soften during an erection. Because proper firmness depends on blood flow through the arteries and relaxation of the spongy tissue in the penis, blocking off leaky veins makes sure there is enough blood trapped in the penis to create a good erection. Since long-term success rates are less than 5%, this technique is rarely a choice for correcting ED.

Vascular surgeries are still thought of as experimental by some, and may not be covered by your health plan.

Neither the penile arterial revascularization or venous ligation surgeries are recommended if you use tobacco or have:

  • insulin-dependent high blood sugar
  • widespread hardened arteries
  • high blood serum cholesterol levels
  • injured nerves
  • diseased and/or wide-spread damaged blood vessels

After Treatment

All of the treatments for ED, except for implant surgery, are used when needed and wear off afterwards. The treatments help but do not fix the underlying problem in the penis. It is important to talk with your health care provider and let him or her know how the treatment is working for you. If your erection is not stiff enough or doesn't last long enough, and you are still troubled, you should discuss other options.

More Information

Frequently Asked Questions

How do I know my ED is not in my head?

It's hard to know. Health providers now realize that most men have an underlying physical cause of ED, and that often both physical and psychological factors will affect ED. It is impossible to prove that there is no psychological part to a man's ED.

If I worry about being able to get an erection, can I make a bad condition worse?

Nothing happens in the body without the brain. Worrying about your ability to get an erection can make it difficult to get one. This is called performance anxiety and can be overcome with education and treatment.

Can I combine treatment options?

This is often done. But because erections can last too long with drug therapy, combining treatment should only be done after talking with your health care provider. Ask your doctor for proper instructions.

I was fine until I began taking this new drug, what should I do?

Never stop or change any drug without first talking to your health care provider. Many drugs can cause ED, but some cannot be changed because the health benefits of the drug are too important. If you are certain that a specific drug has caused the ED problem, ask your health care provider if you can change drugs. If you must stay on the drug that is causing the problem, many ED treatments can be used and can help.

What Questions Should I Ask My Health Care Provider?

  • What is ED?
  • What causes ED?
  • Can ED be prevented?
  • Can you help me, or do I need to see a specialist in ED? If so, how can I find the right one for me?
  • Will I need to have tests to find out what is causing my ED? Why are you recommending them?
  • What types of treatments are available for ED?
  • What treatment do you suggest for me and why?
  • Are there side effects from treatment?
  • What are the pros and cons of each type of treatment you recommend for me?
  • What happens if the first treatment doesn't help?
  • Are there any lifestyle changes I can make that could help my symptoms?