Being suddenly unable to pass urine, despite a full and painful bladder, is a medical emergency. It is called acute urinary retention. It is more common in older men, and an enlarged prostate is the most frequent cause. Knowing what to do can save time and discomfort.
What acute urinary retention feels like
Typical signs include:
- a strong urge to pass urine but being unable to do so
- pain or discomfort in the lower abdomen, often severe
- a swelling you can feel above the pubic bone
- restlessness and distress
Some men can pass only a few drops. Others cannot pass any urine at all.
What to do straight away
If you cannot pass urine and are in pain, seek urgent medical help. Go to an emergency department or call 111 for advice. In the meantime:
- Try sitting in a warm bath, which can sometimes relax the muscles enough to let urine flow.
- Do not drink large amounts of fluid to try to force things.
- Do not take extra medicines without advice.
The NHS guide to urinary retention explains the warning signs.
Why it happens
Retention happens when the outflow from the bladder becomes blocked or the bladder muscle cannot squeeze properly. Common triggers in men with an enlarged prostate include:
- drinking a lot of alcohol in a short time
- delaying passing urine for too long
- constipation
- cold and flu remedies containing decongestants
- some other medicines, such as certain antidepressants or strong painkillers
- a urine infection
- after an operation or general anaesthetic
Our guide to what an enlarged prostate is explains why the prostate can narrow the urethra.
Emergency treatment
The first step is to drain the bladder. A doctor or nurse passes a catheter, a thin flexible tube, through the penis into the bladder. Relief is usually immediate. If a catheter cannot be passed through the urethra, it may be placed through the lower abdomen instead.
The amount of urine drained is recorded, as this helps guide what happens next. Blood tests may check kidney function.
What happens next
Many men go home with the catheter in place for a short period. You may be started on an alpha blocker, a medicine that relaxes the prostate. Our guide to BPH medication explains how it works.
After a few days, a trial without catheter is usually arranged. The catheter is removed to see whether you can pass urine normally. Some men can, especially if a clear trigger was found, such as constipation or a cold remedy. Others need the catheter replaced, and a plan for longer-term treatment is then made.
Longer-term treatment
If retention returns, or if the bladder was holding a large amount of urine, treatment to relieve the blockage is usually recommended. Options may include:
- TURP or laser surgery
- Aquablation therapy, which can treat a wide range of prostate sizes
- prostate artery embolisation, in suitable men
Your urologist will assess your bladder and prostate before recommending a procedure. NICE guidance on urinary symptoms in men sets out when surgery should be offered.
Chronic retention
Some men develop retention slowly, without pain. The bladder gradually stretches and does not empty fully. Signs can include dribbling, leaking at night or frequent small trips. Chronic retention also needs assessment, as it can affect the kidneys.
Reducing your risk
If you have an enlarged prostate, avoid binge drinking, treat constipation, check cold remedies with a pharmacist and do not delay going when you need to. Our page on benign prostatic enlargement explains the treatments that can reduce the risk.
Professor Prokar Dasgupta sees men after an episode of retention at The London Clinic. Please contact the clinic to arrange follow-up.