Urinary Retention in Dogs: Causes and Treatment
By Dr. Zubair Khalid, DVM, MS, PhD ·
Urinary retention in dogs means your dog is unable to pass urine even though the bladder is full. This is different from a dog who dribbles urine or has accidents indoors. A blocked or non-working bladder is a medical emergency that can become life-threatening within hours.
This article is educational and is not a substitute for veterinary diagnosis or treatment.
Quick Answer
- A dog who strains to urinate and produces little or nothing needs emergency veterinary care today, not a wait-and-see approach.
- The two main reasons are a physical blockage of the urethra (the tube that carries urine out) and a bladder muscle that cannot squeeze properly.
- Urinary retention in dogs after surgery is common and often temporary, but it still needs veterinary attention.
- Never press on a full bladder to try to empty it. You can rupture it.
- Treatment depends on the cause and may include a urinary catheter, medications, or surgery.
What Urinary Retention in Dogs Actually Means
Micturition is the medical word for urinating. Disorders of micturition fall into two broad groups: problems with storing urine and problems with voiding it [1]. Urinary retention belongs to the second group.
In a dog with retention, urine is made normally by the kidneys but cannot leave the body. The bladder stretches and stays full. The dog may strain, squat, or lift a leg over and over with nothing coming out, or only a few drops.
This is not the same as incontinence, where urine leaks out without the dog's control. It is also not the same as a dog who urinates small amounts frequently because of a bladder infection. You can read more about that pattern in our guide to Dog Urinating Small Amounts Frequently: Causes and When to Worry.
Prolonged bladder distention damages the tight junctions between the detrusor muscle cells, the muscle that squeezes the bladder. When those junctions break down, the muscle cannot depolarize and contract normally [2]. In plain terms, a bladder that stays too full for too long stops working well, even after the original problem is fixed.
Signs Owners Notice (Urinary Retention in Dogs Symptoms)
The most telling sign is effort without results. Your dog tries to urinate and almost nothing comes out.
Watch for these urinary retention in dogs symptoms:
- Straining to urinate, sometimes for minutes at a time
- Squatting or lifting a leg repeatedly with little or no urine produced
- A hard, swollen, or tender belly
- Crying or whining while trying to urinate
- Pacing, restlessness, or inability to settle
- Vomiting, loss of appetite, or unusual tiredness
- Dribbling small amounts of urine without control (overflow)
- Blood in the urine or a strong urine smell
Some dogs with a partial blockage still pass a thin stream or dribble. That can look like improvement, but it is not. A partial obstruction often becomes complete.
Dogs with urolithiasis, meaning bladder or urethral stones, commonly show abdominal pain, painful urination, blood in the urine, and urinary retention [3]. If your dog has any of these signs along with a hard belly, treat it as an emergency.
Causes and Risk Factors
Physical Blockage of the Urethra
A blockage is the most common cause of sudden, complete retention in male dogs. The urethra in male dogs is long and narrow, so stones and other material get stuck more easily.
Causes of blockage include:
- Bladder or urethral stones (uroliths). Struvite and calcium oxalate are the most common stone types in dogs [4].
- A tumor or mass pressing on or growing into the urethra. In one reported case, a perineal liposarcoma caused severe narrowing of the urethra and three days of straining to urinate [5].
- Scar tissue or a stricture inside the urethra.
- A foreign body, including surgical material. One dog developed complete urethral obstruction after a surgical sponge migrated into the bladder and formed stones around it [6].
Bladder Muscle That Cannot Contract
Sometimes there is no physical blockage. The bladder muscle simply fails to squeeze. This is called bladder atony or detrusor hypocontractility.
This happens when the bladder has been overstretched for a long time. It can also follow spinal cord injury, nerve damage, or certain neurologic conditions. A dog with an atonic bladder may have a large, floppy bladder that never empties fully.
Urinary Retention in Dogs After Surgery
Urinary retention in dogs after surgery is a recognized problem, especially after procedures near the spine, pelvis, or urinary tract. Anesthesia, pain, nerve irritation, and swelling can all interfere with normal urination.
Some dogs also hold urine because it hurts to move into a normal position. Others have a bladder that was overstretched during the procedure and needs time to recover its squeeze.
Most post-surgical retention improves within a day or two with monitoring and support. Some dogs need a catheter for a short time. If your dog has not urinated within the timeframe your veterinarian gave you, call right away.
Other Risk Factors
- Male sex, because of the longer, narrower urethra
- A history of bladder stones or urinary tract infections
- Prior pelvic trauma or urethral surgery
- Certain medications that affect bladder or sphincter tone
- Older age and underlying neurologic disease
How Veterinarians Diagnose the Problem
Diagnosis starts with a physical exam. Your veterinarian will feel your dog's abdomen to check bladder size and firmness. A very large, tight bladder is a red flag.
Next steps often include:
- Watching your dog urinate, if possible, to see the stream and effort
- Urinalysis to check for blood, crystals, infection, and concentration
- Blood work to check kidney values and electrolytes. In obstructed patients, high urea and creatinine are common findings [7].
- Imaging such as X-rays or ultrasound to look for stones, masses, or bladder wall changes. Ultrasound is a standard tool for telling urolithiasis apart from cystitis in dogs [3].
- Contrast studies or advanced imaging when a stricture or tumor is suspected. Retrograde urethrography can show exactly where the urethra narrows [5].
Your veterinarian may also test whether the bladder can be expressed by hand. If manual expression or voluntary voiding does not work, the problem may be excessive urethral sphincter tone, which points to a different treatment path [2].
| Finding | What It Often Means |
|---|---|
| Large, firm bladder plus straining | Blockage or bladder atony |
| Small, frequent urination with blood | Cystitis or stones, not always true retention |
| High kidney values on blood work | Urine has been backing up, kidneys under stress |
| Stones seen on imaging | Urolithiasis, may need surgery or dissolution diet |
| No blockage but bladder will not empty | Detrusor muscle failure or nerve problem |
Treatment Options for Urinary Retention in Dogs
Treatment depends on whether the problem is a blockage or a muscle that will not squeeze. In both cases, the first goal is the same: get urine out safely.
Emergency Decompression
If the bladder is severely distended, your veterinarian will place a urinary catheter to drain it. This relieves pressure and protects the kidneys. In some cases, a needle is used through the belly wall to remove urine quickly.
Do not attempt to express a blocked bladder at home. A full bladder can rupture.
Medications
When the urethral sphincter is too tight, an alpha-adrenergic antagonist may help relax it. Phenoxybenzamine, an irreversible alpha-adrenergic antagonist, has been used with some success for this purpose [2]. Prazosin is another option your veterinarian may try [2].
When the bladder muscle itself is weak, bethanechol may be given to increase detrusor contraction. It is often combined with frequent catheterization to keep the bladder empty while the muscle recovers [2].
Doses for all of these drugs are calculated by your veterinarian based on your dog's weight and health status. Never give human urinary medications to your dog.
Managing Stones
If stones are the cause, treatment may include surgery to remove them, a therapeutic urinary diet to dissolve struvite stones, or both. In one case series, complete dissolution of suspected struvite uroliths occurred in 9 of 13 dogs fed a therapeutic multipurpose urinary food along with antimicrobial therapy [8].
Calcium oxalate stones do not dissolve with diet and usually need surgical removal. Our article on Canine Urolithiasis: Diagnosis and Medical Management covers this in more detail.
Surgery
Surgery is needed when a mass, stricture, or non-dissolvable stones block the urethra. Procedures range from removing stones from the bladder to more complex reconstructions. In one case, a dog with a stent-related urethral obstruction was treated with an intra-abdominal urethral anastomosis, and the surgery successfully bypassed the blockage [9].
Some male dogs need a permanent opening created for urine to pass, called a urethrostomy. This is usually a last resort when the urethra cannot be repaired.
Supportive Care
Many dogs need intravenous fluids to correct dehydration and electrolyte problems. Obstructed patients often have acid-base and electrolyte imbalances that must be corrected before they are stable [7]. Pain control and monitoring of kidney values are also part of care.
Recovery, Outlook, and Long-Term Management
How well a dog recovers depends on how long the bladder was distended and what caused the problem.
Dogs treated quickly for a simple blockage often urinate normally within a day or two. Dogs whose bladders were overstretched may need a catheter and medication for several days while the muscle regains tone [2].
Long-term management may include:
- A prescription urinary diet to reduce stone recurrence
- Regular urine testing and imaging to catch new stones early
- Medications to support bladder emptying if nerve damage is permanent
- Monitoring for urinary tract infections, which are common after catheterization
- Hand expressing the bladder at home if your veterinarian teaches you how
Some dogs with permanent nerve damage never regain full bladder function. These dogs can still live good lives with a managed emptying schedule.
If your dog leaks urine without control after treatment, that is a different problem. Our guide to Why Is My Dog peeing in sleep? Urinary Incontinence and Hormone Deficiency explains the difference.
Prevention
You cannot prevent every cause of urinary retention, but you can lower the risk.
- Feed a diet your veterinarian recommends for your dog's stone type.
- Make sure your dog always has fresh water and plenty of chances to urinate.
- Treat urinary tract infections promptly.
- Keep up with routine wellness visits, especially if your dog has had stones before.
- Watch for early signs like straining or frequent small urinations, and call your vet before it becomes complete retention.
Limitations and When to Contact a Veterinarian
This article cannot tell you what is wrong with your specific dog. Only a veterinarian who examines your dog can do that.
Call your veterinarian the same day if your dog is straining to urinate, passing only drops, or has a history of stones and seems uncomfortable.
Go to an emergency clinic now if your dog:
- Has a hard, swollen belly
- Has produced no urine for more than a few hours
- Is vomiting, weak, or collapsing
- Is crying out or unable to settle
- Has not urinated within the window your veterinarian gave you after surgery
A complete blockage can cause kidney damage and death within 24 to 48 hours. Do not wait to see if it passes.
Frequently Asked Questions
How long can a dog go without urinating before it is dangerous?
A dog with a complete blockage can become critically ill within 24 hours. Kidney values rise quickly when urine backs up. If your dog has not urinated in 12 hours and is straining, treat it as an emergency.
Can urinary retention in dogs resolve on its own?
A partial blockage sometimes improves briefly, but it usually returns and gets worse. Bladder muscle weakness from overstretching rarely fixes itself without help. Waiting gives the bladder more time to lose function.
Is urinary retention after surgery normal?
Some temporary difficulty is common after anesthesia and certain procedures. A dog who cannot urinate at all after surgery is not normal. Call your veterinarian if your dog has not urinated by the time they told you to expect it.
What is the difference between urinary retention and incontinence?
Retention means urine stays trapped in a full bladder. Incontinence means urine leaks out without control. A dog can have both, because a very full bladder often overflows and dribbles.
Can I express my dog's bladder at home?
Only if your veterinarian has examined your dog and taught you how to do it safely. Never press on a bladder you think is blocked. You can cause a rupture, which is a life-threatening emergency.
Related Articles
- Why Is My Dog peeing in sleep? Urinary Incontinence and Hormone Deficiency
- Why Is My Dog Peeing So Much?
- Dog Urinating Small Amounts Frequently: Causes and When to Worry
- Canine Urolithiasis: Diagnosis and Medical Management
- Glomerulonephritis in Dogs: Protein-Losing Nephropathy and Therapy Options
- Signs Of Uti In Dogs
- Urinary Blockage in Dogs: Symptoms and Treatment
- Why Is My Dog Leaking Urine? Causes and When to Worry
- Why Is My Senior Dog Peeing Less Often? Causes and When to Worry
References
- Disorders of Micturition in Dogs and Cats - Urinary System. Merck Veterinary Manual.
- Pharmacotherapeutics in Urine Retention in Animals - Pharmacology. Merck Veterinary Manual.
- Comprehensive diagnostic evaluation of urolithiasis and cystitis in K9 dogs in Iraq: Clinical, laboratory, and imaging correlates. Open veterinary journal, 2025.
- Neutrophil Extracellular Traps Promote Urolithiasis Formation in Dogs: A Preliminary Study. Animals : an open access journal from MDPI, 2026.
- Surgical management of urethral obstruction secondary to perineal liposarcoma in a dog: a case report. BMC veterinary research, 2024.
- Case report: Transmural migration of a gossypiboma with secondary cystolithiasis and urethral obstruction. Frontiers in veterinary science, 2024.
- A retrospective description of blood and urine alterations in 386 male cats with urethral obstruction in Botucatu, São Paulo, Brazil. Open veterinary journal, 2024.
- Outcomes of medical dissolution for suspected struvite uroliths in dogs using a therapeutic multipurpose urinary diet and antimicrobial therapy. Journal of veterinary internal medicine, 2026.
- Penile urethral anastomosis to the vesico-urethral junction, after transabdominal wall passage of the penis, as treatment for intrapelvic stent-related urethral obstruction in a dog. Veterinary surgery : VS, 2025.