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When Straining to Urinate Becomes a Medical Emergency

Analysis by Dr. Karen Shaw Becker

  • February 12, 2020


  • A urinary tract obstruction in dogs is a true medical emergency — especially if the blockage is total vs. partial
  • The classic sign of a urethral obstruction is straining to urinate, along with passing small amounts of urine frequently, or in the case of a complete blockage, the inability to urinate at all
  • The most common cause of urinary tract obstruction in dogs is urinary stones
  • There are many types of bladder stones that occur for a variety of reasons; one of the most important steps in helping your dog avoid urinary crystals and stones is avoiding mineral imbalances and creating dilute urine
  • Additional steps include keeping your dog well-hydrated at all times, and feeding a targeted, moisture rich, species-specific diet with appropriate mineral concentrations



A urinary tract obstruction is a true medical emergency. If your dog has this condition, she (or he) will strain while urinating and pass little to no urine with each attempt. When a pet with the condition strains to urinate, it can actually resemble the hunched posture of a constipated dog.

Urethral obstructions (the urethra is the tube that carries urine from the bladder out of the body) are seen most often in male cats, but also occur in female cats as well as dogs of both sexes. Signs of a partial blockage include:

An interrupted flow of urine

Taking a long time to urinate

Passing small amounts of urine frequently

Urinating in drips rather than a stream

Urinating in inappropriate places

Cloudy, dark or blood-tinged urine

If a dog’s urethra is completely blocked, she’ll strain but won’t produce any urine at all. She’ll be in pain, sometimes to the point of crying out. Other symptoms include lethargy, appetite loss, and possibly vomiting. As the bladder expands, it can be felt in the back half of the dog’s belly and may be painful when touched. It can ultimately rupture, spilling urine into the abdomen.

Dogs with total urethral obstruction will die within days if the blockage isn’t treated, so if your pet isn’t producing the usual amount of urine, and especially if she’s unable to urinate at all, she should be seen a veterinarian immediately.

Diagnosis and Treatment

Your veterinarian will check for signs of acute kidney failure resulting from increased pressure in the renal system and your dog’s inability or compromised ability to eliminate urea and other waste products normally removed from the body in urine.

A baseline blood panel is necessary to determine the appropriate fluids and other treatment that may become necessary, and x-rays or ultrasound may be helpful to determine the cause of the obstruction or other contributing diseases or illnesses. Urinary stones are the most common cause of urethral obstruction in dogs, especially in predisposed breeds such as Miniature Schnauzers, Shih Tzus, the Bichon Frise, Cocker Spaniels and Lhasa Apsos.

The urinary obstruction must be relieved as soon as possible. Depending on the severity of the situation, several methods may be used to remove the obstruction. Urethral massage is one approach that occasionally works.

Alternatively, your veterinarian may try to dislodge the stone by flushing it back into the bladder, which if successful will also clear the urinary opening. The urethra is difficult to perform surgery on, so it’s preferable to try to flush the stone back into the bladder for removal vs. attempting to remove it from the urethra.

If the obstruction can be removed or flushed back into the bladder, a urinary catheter is sometimes left in place for at least 24 hours, depending on the cause of the obstruction. Intravenous (IV) fluids are typically given to rehydrate the dog and normalize electrolyte levels. If kidney damage has occurred, in most cases, it can be repaired with adequate fluid and electrolyte administration. Pain medications may also be necessary.

Sometimes, stones located in the urethra or the ureters (the tubes that connect the kidney to the bladder) must be removed surgically. Surgery to remove a bladder stone is known as cystotomy.

The stones must be submitted for analysis to determine their mineral constitution so dietary management can be instituted. This is the best way to prevent a recurrence of the problem. Failing to identify what type of bladder stone was present means not identifying the root cause(s) of why the stone formed.

If your pet has been diagnosed with urinary stones, it’s imperative that you continue treatment until the condition is resolved, and then incorporate a proactive prevention plan to avoid recurrence. A urinalysis should be completed monthly until all the crystals (the material that forms into stones) are dissolved and then every 6 months to insure the problem isn’t recurring.

The Role of Urine pH in Urinary Stone Formation

Two common denominators in many cases of urinary crystals and stones of all types are super concentrated urine and an underlying urinary tract infection (UTI). So, two things that should happen right away include:

  • Adding moisture to your dog’s diet
  • Having your veterinarian confirm your pet does not have a UTI (or resolving the bacterial infection if present)

Urine pH contributes to stone formation by creating a variety of environments in the bladder that allow for precipitates or mineral sedimentation to occur. There are many different types of urinary crystals that can develop, and when crystals coalesce to form bladder stones, the possibility for obstruction skyrockets.

Veterinarians can get an idea of the type of bladder stone present by evaluating the breed, diet and urinary pH of the dog, as well as the type of crystals indicated by the urinalysis.

Unaddressed bladder infections are one reason stones occur, so if your dog has been diagnosed with a UTI, creating a healthy urine pH will be a part of treating and preventing recurrent infections.

To reduce the likelihood of opportunistic bacteria setting up shop in your dog’s bladder, he should have a slightly acidic urine pH, optimally between 6 and 6.5. A pH of 7 is neutral. Everything above 7 is alkaline, and everything below 7 is acidic.

You want to maintain the urine pH at no more than 7, because a higher pH will predispose your pet to developing struvite crystals and stones. A urine pH above 7 creates a perfect environment for bacterial proliferation as well as sediment to form in the bladder (often called ‘bladder sludge’).

I recommend buying pH strips from your veterinarian or at the local drug store to check your dog’s urine pH at home, so you know when it’s in or outside the desired range. In the morning prior to feeding your dog is when you should collect the urine sample because food profoundly alters urine pH throughout the day.

You can either hold the pH tape in the stream of urine while your dog is voiding, or you can catch a urine sample in a container and dip the tape into the sample to check the pH. This should be done immediately with a fresh sample to ensure accuracy.

It’s a good idea to keep a log of your pet’s morning urine pH to show to your veterinarian at your appointments.

Some types of urinary crystals form more easily in hyper-acidic or alkaline urine, so depending on what type of crystal or stone is present, your vet may suggest a target pH that is slightly higher or lower to keep your dog’s urine pH in a more stone resistant range. Most importantly, the only way to know if your plan is effective is to run a urinalysis regularly as suggested by your vet.

Food (and Additional Recommendations)

Often, a dog’s urine pH can be maintained naturally between 6 and 6.5, on a nutritionally optimal, fresh, species-specific diet. My strong preference is an appropriate home-cooked diet, which you can create with guidance from a veterinary nutritionist at Balance IT, Animal Diet Formulator or private nutritionist with experience in formulating for specific uroliths.

Custom diets are formulated to contain optimal amounts of minerals from real food — enough to meet a dog’s nutritional requirements but not so much that they contribute to stone formation.

Excessive minerals combined with genetic predispositions and concentrated urine often sets the stage for recurrent urinary issues. Providing adequate amounts of minerals from whole food sources is one of the best ways of assuring mineral excesses won’t contribute to more stones in the future.

Macronutrient ratios (the amount of protein, fat and carbohydrates) can be easily adjusted to meet the needs of dogs with different types of bladder stones, as can the amounts of certain vitamins and minerals that help or hinder stone formation. The exact dietary recommendations will depend on what type of stone your dog has been diagnosed with.

Many veterinarians, including myself, have seen many cases of “therapeutic diet” failures when it comes to managing bladder stones. In my opinion, you’re much better off adding urinary pH modulators as needed, such as DL-methionine (decreases urinary pH) or potassium citrate (increases urinary pH) to a homemade or commercially available balanced, fresh food diet.

A targeted nutritional plan in combination with infection management is often much more effective at dissolving urinary stones thanks to high moisture content and nutrients from real foods (not excessive synthetics), but it can take a few weeks to several months for the stones to completely disappear (and some stones do not dissolve, so monitoring is important).

One recommendation that holds for all animals dealing with urinary crystals or stones: ensure they remain optimally hydrated. You might want to consider providing a water fountain with continuously filtered (chemical free), fresh, running water to encourage your pet to drink, along with placing bowls of fresh water in multiple locations around the house.

Evaluating the mineral content of your water may also be important in preventing bladder stones going forward, depending on the type of stone your dog was diagnosed with.

If you have a dog that doesn’t drink a lot of water, you can also add low-sodium bouillon or stock to the water or food to entice her to consume more water. Definitely avoid kibble (it has an extremely low moisture content of 10% to 12%) and choose canned, raw, or fresh food diets with substantially more moisture.

Holistic and integrative veterinarians often use traditional Chinese medicinals, homeopathy, and nutraceuticals, including glucosamine and probiotics to help reduce bladder inflammation in patients prone to urinary stones. D-mannose can help prevent future infections once any current infection has been correctly identified and treated.

Herbs that may benefit certain bladder stone formers include chanca piedra, dandelion, goldenseal, horsetail, marshmallow, plantain, Oregon grape, uva ursi, yarrow, maitake mushrooms, corn silk powder, and olive leaf.

I strongly recommend all dogs with any type of urinary crystals or stones also be given good quality omega-3 fatty acids, such as krill oil, which help reduce systemic inflammation in the body.