Benign prostate enlargement can sometimes lead to complications, such as a urinary tract infection or acute urinary retention.

Urinary tract infections

If you're unable to empty your bladder properly, there's a risk that bacteria in your urinary system won't get flushed out and will spread through the urine to cause a urinary tract infection (UTI).

Symptoms of a UTI include:

• cloudy, bloody or bad-smelling urine
• pain in your lower abdomen (tummy) 
• nausea
• vomiting
• shaking and chills
• a high temperature of 38C (100.4F) or above 

UTIs can be treated with antibiotics. A single UTI isn't usually serious, but repeated UTIs can damage your kidneys and bladder. If you have a history of repeated UTIs, you may need to have surgery.

Acute urinary retention

Acute urinary retention (AUR) is the sudden inability to pass any urine. AUR should be treated as a medical emergency, because without prompt treatment urine may be passed back up into the kidneys, which can damage them.

Symptoms of AUR include:

• the sudden inability to pass urine
• severe lower abdominal pain
• swelling of the bladder that you can feel with your hands

Dial 999 and ask for an ambulance if you or someone you know experiences the symptoms of AUR.

AUR can be treated using a thin tube (catheter) to drain the urine out of your bladder. In very serious cases, surgery may be required to empty the bladder.