It’s not known what causes many cases of prostatitis. A bacterial infection is only sometimes responsible.

In many cases of chronic (long-term) prostatitis, doctors can’t find any infection in the prostate gland, although they may still prescribe a course of antibiotics. In these cases, the cause is poorly understood.

Chronic prostatitis is thought to be caused by a number of suggested factors, including partial blockage of the flow of urine and underlying problems with the immune system, pelvic floor or nervous system.

Bacterial infection

Acute prostatitis (when symptoms are sudden and severe) is usually caused by bacteria in the urinary tract entering the prostate.

However, it’s less clear what happens in cases of chronic bacterial prostatitis. Doctors aren’t certain how bacteria can infect the prostate and cause persistent symptoms that come and go over many months.

One theory is that bacteria spread from the urinary tract or bowel to the prostate and create what’s known as a biofilm on the inner surfaces of the prostate. A biofilm is a small but highly concentrated colony of bacteria that’s covered by a sticky, protective surface – a bit like the plaque that can sometimes develop on teeth.

Your GP will be able to diagnose prostatitis by asking about your symptoms and carrying out a number of tests.

This page outlines how your GP will diagnose both acute and chronic prostatitis.

Diagnosing acute prostatitis

If you have acute prostatitis, your symptoms will be severe and will have started suddenly.

Your GP will take a sample of your urine, which will be checked for the presence of bacteria.

Your GP may also perform a rectal examination. They will insert a finger into your rectum (bottom) and, because the rectum is close to the prostate gland, they’ll be able to determine whether your prostate is inflamed.

The above tests may reveal that you have acute bacterial prostatitis.

Diagnosing chronic prostatitis

Chronic prostatitis (symptoms are less severe but persistent) is diagnosed by asking about your symptoms and ruling out other conditions that could be causing these symptoms.

In order to rule out these types of conditions, you may be given a rectal examination and blood tests.

Imaging studies, such as an ultrasound scan or CT scan, may also be used to help determine the cause of any symptoms.

Instruments, such as a cytoscope, can be used to look at your bladder. A cytoscope is a flexible tube that has a light and a camera at the end.

A cytoscope is placed up into your urethra (tube through which urine passes) and is used to look at your bladder.

The following symptoms may help your doctor to make a diagnosis of chronic prostatitis:

• you have pain in your pelvis, genitals or buttocks
• you feel pain when urinating
• you feel pain when ejaculating
• you have problems with urinating, such as a frequent need to urinate, or a feeling that you haven’t emptied your bladder properly after urinating
• the symptoms have persisted for three months or more
• other possible causes of your symptoms have been ruled out

A urine test or a semen test can be taken to help distinguish between bacterial and non-bacterial chronic prostatitis.

Prostatitis is a general term that refers to inflammation (swelling) of the prostate gland, which is sometimes caused by an infection. It can be very painful and you’ll need to see your GP.

The prostate is a small gland found only in men, which lies between the penis and the bladder (see the box on this page for more information about the prostate gland).

Symptoms of prostatitis include:

• pain when urinating
• pain when ejaculating semen 
• problems urinating
• discomfort in the pelvis, genitals, lower back and buttocks

These symptoms usually come and go over a period of months, but can sometimes start suddenly and be a medical emergency (see below).

Prostatitis can develop in men of all ages, unlike other types of prostate disease (such as prostate cancer or prostate enlargement), which usually affect older men.

Acute vs chronic prostatitis

There are two main types of prostatitis:

• Chronic prostatitis – the most common type. Symptoms will have lasted for at least three months, although they may come and go and vary in severity. The cause isn’t always clear.
• Acute prostatitis – symptoms are severe and develop rapidly. This is caused by a bacterial infection of the prostate gland. It’s a medical emergency, as without prompt treatment with antibiotics, the prostate and surrounding areas can become damaged. An estimated one in every 10,000 men will develop acute prostatitis.

Read more information about the causes of prostatitis.

Outlook

Chronic prostatitis can be challenging to treat, as little is known about the cause of the condition. In most cases, there isn’t any bacterial infection.

Prostatitis caused by a bacterial infection will usually be successfully treated with antibiotics. Most men will make a full recovery within two weeks. Some men may find that symptoms return in the future, which will require further treatment.

Read more information about how prostatitis is treated.

The Map of Medicine is used by doctors throughout the NHS to determine the best treatment options for their patients. NHS Choices offers everyone in England exclusive and free access to this cutting-edge internet resource, which lets you see exactly what your doctor sees.

The information in the Map has been approved by the UK’s leading clinical experts, is based on the best available clinical evidence, and is continually updated. To take advantage of this unique resource go to:

Map of Medicine: male urinary tract symptoms

Map of Medicine: prostatitis

Most men with prostatitis will have a persistent (chronic) form of the disease, where symptoms come and go for at least three months.

Possible symptoms of chronic prostatitis are:

• pain in the pelvis, genitals, lower back and buttocks
• pain when urinating
• frequent need to urinate
• difficulty urinating, such as problems starting or ‘stop-start’ urination
• pain when ejaculating, which may contribute to erectile dysfunction
• discomfort in the perineal area (the area between the scrotum and the anus)

The symptoms may vary from day to day: some days they may be particularly troublesome, on other days they may be mild or almost non-existent.

Sometimes you may also experience tiredness, joint pain, muscle pain and a high temperature.

Medical emergency

If the symptoms of prostatitis are severe and develop suddenly, see your GP immediately. This sudden, severe type is known as acute prostatitis and needs to be treated immediately.

You’ll need to take a course of antibiotics if your prostatitis is caused by a bacterial infection.

However, in many cases of prostatitis there’s no infection and the cause is uncertain, which makes it challenging to treat.

This page outlines the treatment of both acute (sudden, severe) and chronic (longer-lasting) prostatitis.

Treating acute prostatitis

Acute prostatitis is caused by a bacterial infection of the prostate gland and will be treated with antibiotic tablets. Most people will need a four-week course. Your symptoms should pass within two weeks, but it’s very important that you finish the course of antibiotics to prevent the infection returning.

The pain can be relieved using paracetamol or ibuprofen. If your pain is particularly severe you may be prescribed a stronger painkiller, such as codeine.

Treating chronic prostatitis

If chronic prostatitis appears to be caused by a bacterial infection, you’ll need to take a four to six week course of antibiotic tablets. You may also be prescribed a type of medication known as an alpha-blocker.

Alpha-blockers help to relax the muscles in the prostate gland and the base of the bladder and can therefore improve problems with urination, such as difficulty passing urine.

The possible side effects of alpha-blockers include:

• dizziness
• headaches
• weakness
• little or no sperm when you ejaculate

Once you have completed your course of antibiotics, you’ll be given a urine or semen test to check whether any bacteria remain in your prostate or near it. If the test is positive, a further course of antibiotics may be needed.

As with acute prostatitis, paracetamol and ibuprofen can be used to help relieve any pain.

If the cause doesn’t appear to be a bacterial infection, antibiotics aren’t necessary. In this case, you’ll just be treated with alpha-blockers, paracetamol and ibuprofen.

A number of other medications have been used to treat non-bacterial chronic prostatitis, but there is only limited evidence that they’re effective. These medications include:

• finasteride – a medication usually used to treat prostate enlargement
• fluoxetine – an antidepressant medication usually used to treat depression
• gabapentin – a medication used to treat chronic pain
• amitriptyline – a medication used (in low doses) to treat pain, bladder problems and aid sleep