Priapism is a prolonged erection of the penis. The unwanted, persistent erection isn't caused by sexual stimulation or arousal, and priapism is usually painful.
Priapism is an uncommon condition that needs immediate medical attention. Prompt treatment for priapism is usually needed to prevent tissue damage that could result in the inability to get or maintain an erection (erectile dysfunction).
Priapism is most common in boys between ages 5 and 10 years old and in men from ages 20 to 50 years.
Priapism causes abnormally persistent erections. Priapism symptoms vary somewhat depending on the type of priapism.
When to see a doctor
If you experience a painful, persistent erection that resolves on its own in less than four hours, see your doctor, because you may need treatment to prevent further episodes.
An erection normally occurs in response to physical or psychological stimulation. This stimulation causes certain blood vessels to relax and expand, increasing blood flow to spongy tissues in the penis. Consequently, the blood-filled penis becomes erect.
After stimulation ends, the blood flows out, and the penis returns to its nonrigid (flaccid) state.
Priapism occurs when some part of this system — the blood, blood vessels or nerves — changes normal blood flow. Subsequently, an unwanted erection persists. Factors that can contribute to priapism include the following.
Sickle cell anemia, a common cause of priapism, is an inherited disorder characterized by abnormally shaped red blood cells. These abnormally shaped cells can block the flow of blood. Sickle cell anemia is the most common cause of priapism in boys.
Illegal drug use
In some cases, doctors are unable to identify the specific cause for priapism.
Ischemic priapism can cause serious complications. The blood trapped in the penis is deprived of its oxygen supply and becomes toxic to tissues. When the erection lasts for longer than fours hours, the oxygen-poor blood can begin to damage or destroy tissues in the penis. As a result, untreated priapism may cause:
Preparing for your appointment
If you've had an erection lasting more than four hours, go to the emergency room.
If you've experienced a painful, persistent erection that lasted less than four hours, or if you've experienced multiple unwanted, persistent erections (stuttering priapism), see a doctor. You're likely to see your family doctor or general practitioner first, although you may be advised to make an appointment with a specialist in reproductive and urinary organs (urologist).
If you have time before you see your doctor, it's a good idea to be prepared for your appointment.
What you can do
Preparing a list of questions can help you make sure you cover everything that's important to you. For priapism, some basic questions to ask your doctor include:
In addition to the questions that you've prepared to ask your doctor, don't hesitate to ask questions during your appointment at any time that you don't understand something.
What to expect from your doctor
Your doctor may also order laboratory tests to determine if you have a disease or condition that is causing priapism.
What you can do in the meantime
Tests and diagnosis
If you have an erection lasting more than four hours, you need emergency care. The emergency room doctor will determine first whether you have ischemic priapism or nonischemic priapism. This is necessary because the treatment for each is different, and treatment for ischemic priapism needs to be done as soon as possible.
Your answers to questions, a physical examination and a blood test are usually enough to determine what type of priapism you have. You will have additional tests to determine the underlying cause of priapism, which may need to be treated, usually in a nonemergency setting.
Medical history and exam
Treatments and drugs
Surgery may be necessary in some cases to insert material that temporarily blocks blood flow to the penis. The body eventually absorbs the material. Surgery may also be necessary to repair arteries or tissue damage resulting from an injury.
Depending on the probable cause of the priapism, steps to prevent priapism may include:
Last Updated: 2010-12-03
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