When to see a vet urgently
Contact a vet immediately if you notice any of the following:
- repeated straining with no urine or only drops;
- severe pain, crying or restlessness during attempts to urinate;
- difficulty urinating with vomiting, marked tiredness or failure to eat;
- weakness, unsteadiness or collapse.
Do not wait at home for symptoms to ease. Find a vet near you.
Overview
The urethra is a narrow channel carrying urine out of the bladder. Inflammation of its walls causes swelling and irritation, making urination painful and difficult. Urethritis is often more severe in males than females because the urethra is narrower and obstruction risk is high.
Lower urinary tract symptoms are common in cats, but cannot establish that inflammation is confined to the urethra. A painful bladder condition, stones and urethral obstruction can look similar at home. The term urethritis alone therefore does not identify the cause or treatment.
Causes
- bacterial urinary tract infections;
- urinary stone disease involving stones, tiny stones or gritty material;
- urethral plugs made of mucus and crystals;
- urethral injuries from catheterisation or foreign bodies;
- viral infections, including FHV-1 and calicivirus, indirectly through bladder inflammation;
- chemical irritation from unsuitable medicines or toxins.
Inflammation does not automatically mean bacterial infection. In an otherwise healthy adult cat, bacteria are an uncommon cause of urinary symptoms. Infection becomes more likely in older cats or those with kidney disease, for example. A bacterial cause is investigated through tests rather than inferred from blood in the urine alone.
The roles of the herpesvirus and calicivirus listed above in urinary symptoms have been studied, but a causal link has not been demonstrated consistently. An ordinary respiratory viral infection therefore does not itself confirm urethritis or justify antiviral medication.
Urinary crystals must also be distinguished from actual stones. Crystals can occur without stone disease, and a stone may be present even when no crystals are visible in a urine sample. Finding crystals alone does not explain the symptoms.
Risk factors
- males, with a narrow urethra;
- neutered cats;
- overweight and inactive cats;
- cats with chronic bladder inflammation or urinary stones;
- cats receiving an unbalanced diet.
These factors partly concern lower urinary tract disease and obstruction generally; less is known about the risk of urethritis specifically. Early neutering does not reduce urethral diameter. Symptoms in a neutered cat should therefore not be attributed solely to neutering. A normal-weight or unneutered cat may also need urgent care.
Typical symptoms
- frequent, painful attempts to urinate;
- blood in the urine, known as haematuria;
- passing small amounts or drops;
- vocalising and restlessness while urinating;
- genital licking;
- possible complete urethral obstruction, a life-threatening condition.
Pain can also cause hiding, reduced appetite or urination outside the litter tray. Your cat is not doing this deliberately. Pay attention to actual urine output: repeated visits to the tray do not establish that the bladder is emptying.
Straining may be mistaken for constipation. If you do not know whether your cat is trying to urinate or pass faeces, tell the vet. A few drops do not rule out a developing or partial obstruction. Do not wait until your cat stops trying altogether.
Complications and consequences
- urethral obstruction, particularly in males;
- infection spreading to the bladder and kidneys;
- chronic urethral inflammation and scarring;
- acute kidney failure associated with urinary retention.
With a complete obstruction, urine pressure rises and kidney function is disrupted. Blood potassium can rise dangerously and cause abnormal heart rhythms. Do not wait for a dramatic deterioration before seeking care.
Spread of infection is a possible consequence of bacterial disease. However, not every inflammatory or painful urinary condition is an infection. Persistent difficulty urinating may also result from scarring or another structural obstruction, requiring different treatment from bacterial infection.
Diagnosis at the vet
- routine urine testing for blood, protein, crystals and bacteria;
- urine culture to identify bacteria and antibiotic susceptibility;
- bladder and urethral ultrasound;
- X-rays if stones are suspected;
- urethral and bladder endoscopy in chronic disease.
The first assessment establishes whether urine passes and whether the bladder is large and painful. The vet asks about symptom onset, previous obstructions, medicines and known stones. Blood tests can assess kidney function and electrolyte balance. A seriously ill cat needs treatment during investigations.
If obstruction is suspected, an ECG may assess the heart's electrical activity. It helps detect dangerous rhythm disturbances. Severe electrolyte abnormalities may need correction before anaesthesia, so treating a blockage involves more than inserting a catheter.
A urine sample is examined for concentration, red blood cells, inflammatory cells, crystals and possible bacteria, among other findings. Collection and storage affect interpretation: delay or cooling can increase visible crystals. One finding alone does not show where in the urinary tract a change is located.
For culture, the vet may collect urine directly from the bladder with a needle. This reduces bacterial contamination from outside. A positive culture is assessed alongside symptoms because bacteria may also be present without a true symptomatic infection.
Ultrasound shows bladder contents and the wall well, but cannot show the entire urethra within the pelvis or penis. Normal ultrasound therefore does not rule out every urethral problem. X-rays and, where needed, contrast imaging help look for stones, narrowing or damage. A cat's small size limits the possibilities for endoscopy.
Treatment
Relieving a urethral obstruction is a veterinary procedure. Urine flow is usually restored with a catheter under sedation or anaesthesia, while pain and fluid and electrolyte disturbances are treated. The catheter may remain temporarily. Before discharge, the cat's ability to urinate after catheter removal is confirmed.
Antibiotics are needed when investigations support a symptomatic bacterial infection. Where possible, the medicine is chosen according to culture and susceptibility testing. Blood in urine, crystals or catheter use alone does not automatically require antibiotics. Continuing symptoms need reassessment of the cause, rather than simply changing medicines yourself.
For recurrent or otherwise unresolved obstruction, surgery to create a wider urethral opening may be considered. It can improve urine flow but does not remove a painful bladder disease or prevent new stones. Surgery therefore does not replace treatment of the underlying cause.
Home care and monitoring
After discharge, monitor urine volume, appetite, activity and pain as well as attempts to urinate. Keep the litter tray easily accessible and record changes. If no urine passes, contact the treating practice immediately even if a blockage has only just been relieved.
Do not squeeze the bladder or try to open the urethra yourself. Do not give human painkillers. Follow prescribed medicine instructions; vomiting, diarrhoea, marked tiredness or loss of appetite during medication warrants veterinary contact. Do not add other painkillers on your own.
Licking after surgery can damage the surgical site. The vet explains protective collar use and wound monitoring. Contact the practice if the area swells, bleeds or urination becomes difficult again.
Prognosis
The outlook depends on the cause, obstruction duration and changes in kidney function and general condition. Promptly treated cats may recover well, but symptoms can recur. A new episode may have a different cause, so an earlier diagnosis does not replace reassessment.
Prevention
- Maintain water availability and appropriate feeding.
- Prevent urinary stones with suitable special diets.
- Have bladder inflammation and infections treated promptly.
- Catheterisation should be careful and performed only at a vet's discretion.
- Take at-risk cats for regular veterinary checks.
Wet food and fresh water in several quiet locations can support water intake. Some cats like fountains, while others prefer an ordinary bowl. Make sure another animal cannot block access to water.
A special diet is selected for the diagnosed problem. Struvite stones can sometimes be dissolved through diet, for example, but calcium oxalate stones do not dissolve in the same way. Do not add urine-acidifying products or a randomly chosen urinary diet yourself.
Provide clean, adequately sized litter trays in quiet places. Your cat should be able to reach a tray without jumping or passing another animal. Multi-cat homes need several accessible trays. However, sudden tray avoidance should not be treated solely as an environmental problem before disease has been ruled out.
Important for cat owners
Urethritis is a common condition often associated with bladder inflammation or urinary stones. Remember that difficulty urinating, blood in the urine or pain warrants an immediate veterinary visit. Early help reduces the risk of obstruction and dangerous complications.
It is urinary symptoms in particular that are common; the frequency of urethritis specifically cannot be inferred from them without investigations.
This article provides general information and does not replace veterinary care. If you notice signs of illness in your cat, contact a vet.
Frequently asked questions
Does urethritis always need antibiotics?
No. Inflammation and pain can have causes other than bacteria. The need for antibiotics depends on symptoms, urine testing and culture where necessary.
Can there be a blockage even if drops of urine pass?
Yes. Small drops do not show that the bladder empties. Repeated painful straining and little urine require urgent veterinary contact.
Why do symptoms return if previous treatment helped?
A recurring painful condition, stone, infection or structural problem may be responsible. A different cause from before is also possible. A new episode needs reassessment.
This article is for general information only and is not a guide to treatment. If you notice the first signs of illness, contact your vet.
Paw4care editorial team
Sources
- 2025 iCatCare consensus guidelines on the diagnosis and management of lower urinary tract diseases in cats, Journal of Feline Medicine and Surgery, accessed 2026-11-03.
- Urinary Obstruction in Male Cats, American College of Veterinary Surgeons, accessed 2026-11-03.
- Blocked bladder in cats, PDSA, accessed 2026-11-03.
- Diagnostic testing, AAHA, accessed 2026-11-03.
- Litter Boxes, The Ohio State University, Indoor Pet Initiative, accessed 2026-11-03.
- Hydration, Cornell Feline Health Centre, accessed 2026-11-03.
- Urinalysis, Merck Veterinary Manual, accessed 2026-11-03.
- Get the Facts about Pain Relievers for Pets, U.S. Food and Drug Administration, accessed 2026-11-03.
- Feline Lower Urinary Tract Disease, Cornell Feline Health Centre, accessed 2026-11-03.