Urinary
Medicines for Hydronephrosis
Swelling of a kidney caused by a build-up of urine, usually because something is blocking or slowing its drainage — treated by relieving the blockage.
Education and reference only. This explains which medicines are used and why, in plain language — it deliberately contains no doses and is not a substitute for advice from your doctor or pharmacist. Always discuss your own treatment with a qualified clinician, and check the BNF and the product labelling for prescribing detail.
Quick answer
What is Hydronephrosis?
Hydronephrosis is swelling of a kidney that happens when urine builds up inside it because it cannot drain away normally into the bladder. It is not a disease in itself but a result of another problem — usually something blocking or slowing the flow of urine out of the kidney, or urine flowing backwards from the bladder.
- How it is treated: Management focuses on finding and treating the underlying cause of the drainage problem, and, where needed, relieving the pressure on the kidney to protect its function.
- Self-care: There are no specific self-care measures for hydronephrosis itself; the key is assessment and treating the underlying cause.
- When to seek help: See a doctor about symptoms such as pain in the side or back, difficulty passing urine, or reduced urine output.
What it is
Hydronephrosis is swelling of a kidney that happens when urine builds up inside it because it cannot drain away normally into the bladder. It is not a disease in itself but a result of another problem — usually something blocking or slowing the flow of urine out of the kidney, or urine flowing backwards from the bladder. Common causes include a kidney stone lodged in the tube (ureter) that drains the kidney, an enlarged prostate in men (which can obstruct bladder emptying), narrowing (a stricture) of the drainage tubes, and, in some cases, pressure from outside (such as a cyst or growth); in babies and children, it is sometimes found before or after birth due to a blockage or urine flowing back up from the bladder (reflux). Symptoms depend on the cause and how quickly it develops: a sudden blockage (for example from a stone) can cause severe pain in the side or back, while a gradual blockage may cause few symptoms and be found on a scan. If urine build-up is significant or prolonged, it can affect how well the kidney works, so hydronephrosis is assessed and the underlying cause treated.
How it is treated
Management focuses on finding and treating the underlying cause of the drainage problem, and, where needed, relieving the pressure on the kidney to protect its function. Hydronephrosis is usually found and assessed with imaging (such as an ultrasound or CT scan), which shows the swollen kidney and often the cause, along with tests of kidney function. Treatment then depends on the cause: for example, treating or removing a kidney stone that is blocking the ureter, treating an enlarged prostate, or addressing a narrowing. Where the kidney is significantly obstructed or at risk, the drainage may need to be relieved more urgently — for example by placing a small tube (a stent) inside the ureter to allow urine to pass, or a tube through the skin into the kidney (a nephrostomy) to drain it — while the underlying cause is dealt with. If there is also an infection behind a blockage, this is an urgent situation needing prompt treatment. In babies and children, mild hydronephrosis found before or after birth often improves on its own and is monitored, with treatment reserved for those that need it. The reassuring message is that hydronephrosis is usually treatable by relieving the blockage and addressing its cause, which protects the kidney.
For this condition, these medicines
Medicine classes used for Hydronephrosis
Each links to a full, dose-free guide — what it is, how it works, who can and cannot use it, side effects, interactions and FAQs.
Beyond medication
Lifestyle and self-care
There are no specific self-care measures for hydronephrosis itself; the key is assessment and treating the underlying cause. Staying hydrated is generally sensible. Following advice on any procedure to relieve the blockage or treat the cause, and attending monitoring, are important.
When to get help
When to see a doctor
See a doctor about symptoms such as pain in the side or back, difficulty passing urine, or reduced urine output. Seek urgent care for severe pain, a high fever with urinary symptoms (a possible infection behind a blockage), or being unable to pass urine, which need prompt treatment.
Not sure how urgent it is? It is always OK to call NHS 111 for advice, day or night.
Answers
Hydronephrosis: frequently asked questions
What causes hydronephrosis?
It results from urine not draining away normally, usually because something blocks or slows its flow — commonly a kidney stone in the ureter, an enlarged prostate, or a narrowing — or urine flowing backwards from the bladder. In children it can be found before or after birth.
How is hydronephrosis treated?
By treating the underlying cause (such as a stone or enlarged prostate) and, where needed, relieving the pressure on the kidney — for example with a stent in the ureter or a drainage tube into the kidney — to protect its function. An infection behind a blockage needs urgent treatment.
Sources
Where this is drawn from
- NHS — Hydronephrosis
- British Association of Urological Surgeons guidance
Related conditions
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