Why erectile dysfunction (ED) happens
ED can be caused by things like stress or fatigue. But a lot of times, ED is not something that you can control. That’s because it’s often due to a physical problem that affects your blood flow.

Usually when a man is sexually aroused:
  1. The brain sends an impulse telling the arteries in the penis to widen.
  2. As a result, more blood flows to the penis.
  3. When this happens, the penis expands and hardens. This causes an erection.
When a man has ED, the nerves or blood vessels in the penis don’t work properly. This prevents blood from flowing to the penis. And that can prevent an erection.

Norm’s story
“About four years ago, I encountered a medical problem that was very disconcerting. It was affecting our personal lives. We did not talk about it. It was erectile dysfunction. And it got to the point where I was actually avoiding Bernice. I would stay up late at night and go to bed after she did. Frankly, I was embarrassed. Because, things were not like they used to be. My doctor discovered that I had a hypothyroid condition. And I have to take thyroid medication for the rest of my life. And my doctor felt that this was a contributing factor to my erectile dysfunction condition.”

Real patient featured. Individual results may vary.

Dr. Steven Lamm
“VIAGRA is prescribed to treat erectile dysfunction in men. Here’s important safety information about VIAGRA. Ask your doctor if your heart is healthy enough for sex. Don’t take VIAGRA if you take nitrates for chest pain, as it may cause an unsafe drop in blood pressure. Side effects may include headache, flushing, upset stomach, and abnormal vision. Stop taking VIAGRA and call your doctor right away if you experience a sudden decrease in vision or hearing. To avoid long-term injury, seek immediate medical help for an erection lasting more that 4 hours. Remember, VIAGRA does not protect against sexually transmitted diseases, including HIV. Ask your doctor if VIAGRA is right for you.”

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Norm’s story
“About four years ago, I encountered a medical problem that was very disconcerting. It was affecting our personal lives. We did not talk about it. It was erectile dysfunction. And it got to the point where I was actually avoiding Bernice. I would stay up late at night and go to bed after she did. Frankly, I was embarrassed. Because, things were not like they used to be. My doctor discovered that I had a hypothyroid condition. And I have to take thyroid medication for the rest of my life. And my doctor felt that this was a contributing factor to my erectile dysfunction condition.”

Real patient featured. Individual results may vary.

Dr. Steven Lamm
“VIAGRA is prescribed to treat erectile dysfunction in men. Here’s important safety information about VIAGRA. Ask your doctor if your heart is healthy enough for sex. Don’t take VIAGRA if you take nitrates for chest pain, as it may cause an unsafe drop in blood pressure. Side effects may include headache, flushing, upset stomach, and abnormal vision. Stop taking VIAGRA and call your doctor right away if you experience a sudden decrease in vision or hearing. To avoid long-term injury, seek immediate medical help for an erection lasting more that 4 hours. Remember, VIAGRA does not protect against sexually transmitted diseases, including HIV. Ask your doctor if VIAGRA is right for you.”

Causes of ED
ED is often caused by other health issues that can affect the flow of blood to the penis. No matter what the cause, treatment is usually effective.

Find out why these issues can affect blood flow:

Common causes
High blood pressure
High blood pressure makes the heart work harder. This puts strain on the blood vessels, which then harden and narrow. This can prevent blood from getting to the penis. And that makes it more difficult to get or keep an erection.

More than 65% of men with high blood pressure also have ED.

High cholesterol
High blood cholesterol can clog your arteries. This can slow blood flow to the penis. As a result, it can affect the quality of your erections.

Having high cholesterol raises your risk of ED by 80%.

Heart disease
Heart disease also is known as coronary artery disease.

For a person with heart disease, blood does not flow as easily throughout the body as it should. That’s because the arteries are clogged or narrowed. This may slow blood from getting to the penis and prevent a firm erection.

Diabetes
Diabetes is a condition where there is too much sugar, or glucose, in the blood. Over time, high blood sugar levels can damage nerves and blood vessels like those that produce erections. When this occurs, diabetes often leads to ED.

Up to 85% of men with diabetes have some erection difficulty.

Prostate problems
The prostate is a small gland near your bladder. It is next to the nerves that are needed for erections. That’s why certain treatments for prostate problems can lead to ED.

Other factors
Depression
For men with depression, the cause of ED may be psychological, physical, or both. ED can lower self-esteem and strain your relationship with your partner. And certain medicines that treat depression can cause ED.

Spinal injury
An injury to the spine can affect almost every function in the body. For men with spinal injuries, ED is the most common sexual problem.

Certain medicines
There are many medicines that can cause ED. The most common are:
  • Certain medicines that lower blood pressure
  • Some heart medicines
  • Some cancer medicines
  • Certain medicines for depression
Stress
Stress and anxiety can affect your ability to get an erection. However, they often are not the primary cause of ED. It’s more likely to be a physical problem.

When a physical problem causes erection difficulty, men become more anxious about sex. This can increase the severity of ED.

Smoking and alcohol
Smoking and drinking too much alcohol can lead to ED. Drinking alcohol can temporarily impair the ability to get an erection. To help avoid symptoms of ED, it’s best not to drink large amounts of alcohol before having sex.

If you smoke, you should consider stopping. Smoking can cause cancer, emphysema, chronic obstructive pulmonary disease (COPD), and other illnesses. It also can damage blood vessels. This may prevent blood flow to the penis and can cause ED.

Common causes
High blood pressure
High blood pressure makes the heart work harder. This puts strain on the blood vessels, which then harden and narrow. This can prevent blood from getting to the penis. And that makes it more difficult to get or keep an erection.

More than 65% of men with high blood pressure also have ED.

High cholesterol
High blood cholesterol can clog your arteries. This can slow blood flow to the penis. As a result, it can affect the quality of your erections.

Having high cholesterol raises your risk of ED by 80%.

Heart disease
Heart disease also is known as coronary artery disease.

For a person with heart disease, blood does not flow as easily throughout the body as it should. That’s because the arteries are clogged or narrowed. This may slow blood from getting to the penis and prevent a firm erection.

Diabetes
Diabetes is a condition where there is too much sugar, or glucose, in the blood. Over time, high blood sugar levels can damage nerves and blood vessels like those that produce erections. When this occurs, diabetes often leads to ED.

Up to 85% of men with diabetes have some erection difficulty.

Prostate problems
The prostate is a small gland near your bladder. It is next to the nerves that are needed for erections. That’s why certain treatments for prostate problems can lead to ED.

Other factors
Depression
For men with depression, the cause of ED may be psychological, physical, or both. ED can lower self-esteem and strain your relationship with your partner. And certain medicines that treat depression can cause ED.

Spinal injury
An injury to the spine can affect almost every function in the body. For men with spinal injuries, ED is the most common sexual problem.

Certain medicines
There are many medicines that can cause ED. The most common are:
  • Certain medicines that lower blood pressure
  • Some heart medicines
  • Some cancer medicines
  • Certain medicines for depression
Stress
Stress and anxiety can affect your ability to get an erection. However, they often are not the primary cause of ED. It’s more likely to be a physical problem.

When a physical problem causes erection difficulty, men become more anxious about sex. This can increase the severity of ED.

Smoking and alcohol
Smoking and drinking too much alcohol can lead to ED. Drinking alcohol can temporarily impair the ability to get an erection. To help avoid symptoms of ED, it’s best not to drink large amounts of alcohol before having sex.

If you smoke, you should consider stopping. Smoking can cause cancer, emphysema, chronic obstructive pulmonary disease (COPD), and other illnesses. It also can damage blood vessels. This may prevent blood flow to the penis and can cause ED.


VIAGRA is prescribed to treat erectile dysfunction (ED).

Important safety information

Do not take VIAGRA if you take nitrates, often prescribed for chest pain, as this may cause a sudden, unsafe drop in blood pressure.

Discuss your general health status with your doctor to ensure that you are healthy enough to engage in sexual activity. If you experience chest pain, nausea, or any other discomforts during sex, seek immediate medical help.

As with any ED tablet, in the rare event of an erection lasting more than 4 hours, seek immediate medical help to avoid long-term injury.

If you are older than age 65, or have serious liver or kidney problems, your doctor may start you at the lowest dose (25 mg) of VIAGRA. If you are taking protease inhibitors, such as for the treatment of HIV, your doctor may recommend a 25-mg dose and may limit you to a maximum single dose of 25 mg of VIAGRA in a 48-hour period.

In rare instances, men taking PDE5 inhibitors (oral erectile dysfunction medicines, including VIAGRA) reported a sudden decrease or loss of vision. It is not possible to determine whether these events are related directly to these medicines or to other factors. If you experience sudden decrease or loss of vision, stop taking PDE5 inhibitors, including VIAGRA, and call a doctor right away.

Sudden decrease or loss of hearing has been rarely reported in people taking PDE5 inhibitors, including VIAGRA. It is not possible to determine whether these events are related directly to the PDE5 inhibitors or to other factors. If you experience sudden decrease or loss of hearing, stop taking VIAGRA and contact a doctor right away.

If you have prostate problems or high blood pressure for which you take medicines called alpha blockers, your doctor may start you on a lower dose of VIAGRA.

VIAGRA does not protect against sexually transmitted diseases, including HIV.

The most common side effects of VIAGRA are headache, facial flushing, and upset stomach. Less commonly, bluish vision, blurred vision, or sensitivity to light may briefly occur.

Please see full prescribing information for VIAGRA (25-mg, 50-mg, 100-mg) tablets.

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