Acral lick dermatitis, also known as lick granuloma, is a self-induced skin lesion. The term acral refers to the legs and feet. Acral lick dermatitis mainly is a problem of dogs, rarely cats. The dog continually licks at one area of the leg, producing hair loss, sores, and thickening of the skin. Typical appearance is a raised, red, hairless, oval patch of skin or skin lump found over the front surface of one leg. Occasionally, more than one leg may be affected. The most common locations are over or near the carpus (“wrist”) of the front paw or just below or above the hock on the rear leg. Breeds most likely to develop acral lick dermatitis include the Doberman pinscher, Great Dane, Labrador retriever, Irish setter, golden retriever, and German shepherd, but any breed of dog can be affected.

Males are affected twice as often as females. The condition may appear at any age; however, most dogs are over 5 years of age when presented for treatment. Although several conditions that cause discomfort of the skin can cause persistent licking (see Diagnosis below), in many dogs with acral lick dermatitis no underlying problem can be found. In these cases, acral lick dermatitis is considered a psychogenic disease; that is, it is caused by a behavioral disorder. For example, sometimes excessive licking or chewing can result from boredom or can be used as attention-seeking behavior; sometimes anxiety is the stimulus for stereotypic behaviors like repetitive licking.

Stereotypic behaviors are excessive, repetitive behaviors engaged in to relieve psychological distress such as boredom or anxiety.


Several other skin conditions may appear similar to acral lick dermatitis. These include skin tumors, granulomas (masses due to chronic inflammation), and deep bacterial or fungal infections. In addition, several conditions that cause pain or itching can be involved in the development of lick granulomas, since dogs will lick areas where they feel tingling or discomfort. Depending upon the appearance of the skin lesion and your pet’s history, your veterinarian may need to run several tests to check for similar conditions and underlying disorders, including skin scrapings, bacterial or fungal cultures, and skin biopsies.

In some cases, x-rays may be warranted to look for joint or bone disease, such as arthritis, or bone infections that can cause pain and therefore cause a dog to lick over the painful area incessantly. A history of trauma or surgery in the area might indicate possible nerve damage as a source of discomfort. A variety of conditions that cause itching can contribute to the development of acral lick dermatitis; these include allergies, skin infections, and skin parasites (fleas, mange, etc.).

If no underlying disease can be found, then by exclusion, psychogenic factors are assumed to be the cause of the dog’s constant licking. Therefore the first step in evaluating a dog thought to have acral lick dermatitis is to perform basic tests to assess for other contributory medical and skin conditions (above). Once acral lick dermatitis is confirmed to be the problem, a very valuable form of evaluation is consultation with a veterinary behaviorist. These are veterinarians who specialize in assessment and treatment of behavioral disorders such as acral lick dermatitis. While animal behaviorists are sometimes derided, they are specialty-trained veterinarians whose focus of practice is entirely animal behavior, and their input and recommendations can be lifesaving.

The American Association of Veterinary Behaviorists is a nonprofit veterinary medical association. It regroups the specialty-trained veterinarians around the world who are experts in behavioral problems of dogs and cats (see “For the Public” → “Find a Board Certified Veterinary Behaviorist” at Your veterinarian should be able to refer you to one of these Diplomates in your area, or by telephone, to better identify and correct the psychological/behavioral trigger that is leading to the incessant licking.


Acral lick dermatitis can be challenging to treat. Medications may help, either for direct application or, in the case of behavior-modifying medications, as oral tablets. Often the visible skin lesion is only the surface of the problem, and the root cause is psychological or behavioral. Therefore, the frustration of dealing with a dog that is compulsively licking needs to be met with an understanding that some sort of underlying trigger may exist and that dealing with that trigger is critical to solving the problem.

Response to treatment depends upon correction of the underlying cause. Many cases require long-term care at home and adjustment of treatments when the lesion reappears. It is worth remembering that stressful changes in your pet’s life may precipitate reoccurrence of the problem.


There are many approaches to treating acral lick dermatitis, nd some trial and error is usually needed to find the best treatment for an individual dog. Since deep bacterial infections of the skin usually are present as well (secondary problem due to the damage of licking), antibiotic pills are usually given for several weeks. The affected skin area can be treated directly with a variety of medications, including topical treatments and injections. Bitter-tasting topical solutions are sometimes applied to discourage licking. Most treatments that are applied to the lesion are aimed at altering the sensation in the skin. Agents used include corticosteroids, dimethyl sulfoxide DMSO), capsaicin, antiinflammatory drugs, and antihistamines. Additional treatments aimed at reducing itching or painful sensations include acupuncture, laser surgery, or cryosurgery.

Removal of the lesion with conventional surgery, laser surgery, or cryosurgery is also advocated by some veterinarians. Some degree of relief can also sometimes be brought about by frequently bandaging the leg and/ or placing an Elizabethan collar on the dog to break the cycle of licking-itching. Behavioral components of the condition also need to be addressed. Boredom can be alleviated by increasing playtime, introducing another animal as a playmate, reducing confinement time, or keeping the pet occupied with toys such as those with openings for treats (e.g., Kong-type toys). Several behavioral modification training techniques can be used. Stressful conditions should be eliminated, when possible. Antidepressant and antianxiety drugs may also be helpful in some dogs, and these can be prescribed by your veterinarian or a veterinarian specialized in behavioral medicine.


  • Be diligent and persistent with treatment. Hair regrowth and reduced compulsion to lick happen very slowly (weeks to months).


  •  Avoid blaming or acting exasperated with a dog with acral lick dermatitis. Unfortunately, compulsive licking can truly be exasperating, but yelling at or punishing dogs for doing this simply does not register with them and often can make them more compulsive, which worsens the problem. In other words, harsh words and punishment for licking behaviors tend to be totally counterproductive. Acral ick Dermatitis
  • Don’t assume that the problem is entirely in the skin, or entirely in the dog’s mind. Oftentimes, a combination of behavioral factors and skin factors is to blame for acral lick dermatitis.


  • Persistent licking or chewing at one area on the paw or leg.
  • Hair loss, irritated skin, and eventually a raised, completely hairless, shiny, reddened area of skin.


  • Because determining the best treatment of acral lick dermatitis often requires trial and error, several visits may be necessary to determine the optimal combination of treatments for your dog.
  • Once the right treatment is found, the visits become much less frequent—generally just routine checkups.



From Cohn and Côté: Clinical Veterinary Advisor, 4th edition. Copyright © 2020 by Elsevier Inc. All rights reserved.

Skin problems are common in dogs and cats, and are one of the most frequent reasons that owners bring their pets to the veterinarian. There are many different reasons why a pet will itch and scratch. Fortunately, we can break most of the causes down into a few categories: allergies, skin parasites, and skin infections. 1. Allergies Pollen/environmental allergy (Atopy): Just like people, dogs and cats can be allergic to pollen, dust and molds. But instead of sneezing and hayfever, pets most often show their allergies in their skin. Allergic cats may develop crusty dermatitis or lick their hair so much that they cause bald spots. Allergic dogs may scratch all over, but especially at their armpits, belly and ears. They may also have recurrent skin and ear infections and lick their paws.

The signs usually start between 6 months to 5 years of age. Since food allergy and skin parasites or infections also cause itching, these diseases need to be eliminated as possible causes of itching before the diagnosis of atopy can be made. Some pets with pollen/dust allergies tend to have seasonal (warm weather) symptoms, others may have symptoms year round. Some pollen-allergic pets can be treated symptomatically during the itchy seasons with soothing shampoos/conditioners and anti-itch medications (antihistamines, fatty acids, occasional steroids). If present, secondary bacterial or yeast infections also need to be treated.

Pets with continuous itching or signs that are not well-controlled with symptomatic medications or that need steroids too frequently should be allergy tested to find out what they are allergic to. Allergy testing can be performed with blood tests or skin tests (like scratch testing in people). Blood allergy testing is more convenient and can be performed by most veterinarians, but may be less accurate than skin testing. Skin allergy testing tests the actual organ that is involved in the allergy (the skin), so is more accurate than blood testing, and is typically performed by veterinary dermatologists. Once the allergy test results are known, allergic pets can receive allergy shots (just like people!) to desensitize them to the pollen. Although not a cure or a quick-fix, allergy hyposensitization injections help 70-75% of allergic pets to decrease symptoms and need for other medications, and address the cause of the allergies, not just the symptoms. Food allergy: Animals with food allergy can show very similar signs as pets with pollen allergies, but the itching is not seasonal and animals can develop a food allergy at any time in their life—even if they have been eating the same food all along! Cats may develop crusty dermatitis or hair loss similar to pollen allergy.

Besides itchiness, food-allergic dogs may also have ear or skin infections. The symptoms of food allergy usually do not improve much with antiitch medications, and the diagnosis and treatment is to feed the pet a hypoallergenic diet using a protein source that they have never been exposed to before. Switching to another commercial diet usually does not help, because most of these diets have similar ingredients. A better alternative is a hypoallergenic diet with single unique protein ingredients such as fish, rabbit, duck, or venison, with a single carbohydrate such as potato or rice, and no other treats, table scraps, rawhides, milkbones, chewable supplements or other foods for at last 6-8 weeks. Some food allergic dogs require home cooked hypoallergenic diets.

Blood or skin testing for food allergy is unfortunately not accurate in dogs and cats. If present, secondary bacterial or yeast infections also need to be treated. If the itchy symptoms have resolved in 6-8 weeks, new food allergens can be added one at a time every 2-3 weeks (ie. beef, chicken, lamb, wheat, corn, egg, milk etc.) to determine what the pet is allergic to and what other foods they may tolerate. 2. Skin Parasites Fleas: Fleas cause itching and hair loss due to the irritation caused by their bites, secondary bacterial infections, or to a flea bite allergy. Symptoms are often worse in warm weather when fleas are most numerous. Animals will often itch and lose hair on their back near their tail. Cats may also develop small crusts on their skin that are similar in appearance to tiny millet seeds (miliary dermatitis).

In flea-allergic animals, even one fleabite can cause a reaction. With the availability of the effective veterinary prescription monthly flea treatment products, flea allergy has become easier to treat. Flea control in the home and yard is also important. Treatment of secondary bacterial skin infections and temporary antiitch medication (steroids) are also often needed while the flea problem is being brought under control. Although fleas are uncommon in the Southwest due to our hot dry climate, pets may be exposed when they travel to California or other flea-endemic areas. Mange Mites: There are two common types of mange (tiny, microscopic skin mites): demodex and scabies. Another, less common mite that can cause itchy skin disease is called cheyletiella. All types of mites are diagnosed by microscopic analysis of skin scrapings performed by a veterinarian. Demodex mites can cause patchy hair loss (especially on the face and feet/legs) with only mild itching, or infected dogs can be very itchy if secondary bacterial infections develop.


This mite is more common in puppies and immunosuppressed animals, and is not contagious to other pets or to people. Treatment options include weekly prescription antiparasitic dips, or daily oral antiparasitic prescription medications such as ivermectin or milbemycin. Skin scrapings are monitored monthly by the veterinarian to determine when it is safe to stop medication, and most dogs are treated for an average of 3-4 months. Herding breeds such as Collies, Shelties, Aussies, Border Collies and sheepdogs should not receive ivermectin due to risk of lethal toxicity, and all treatments should be prescribed and monitored by a veterinarian. Scabies: infection, a very itchy and contagious to other dogs, may cause hair loss and a crust to form on their ears and elbows. Scabies mites can be very difficult to find, and often we will trial-treat for scabies based on the dog’s symptoms and appearance, even if we cannot find mites on the skin scrapes.

Treatment options for scabies mange include weekly prescription insecticidal dips for 4-6 weeks, or systemic antiparasitic prescription medications such as Revolution, ivermectin or milbemycin given every 1- 2 weeks for 6 weeks. With scabies, all dogs in the household must be treated at the same time, even if they are not showing signs yet, because some dogs can carry the mites and have no symptoms. Dogs with scabies may also have secondary bacterial or yeast skin infections which contribute to the itch. Again, herding breeds should not receive ivermectin due to risk of lethal toxicity, and all treatments should be prescribed and monitored by a veterinarian.

Cheyletiella mites: cause itchy skin and dry scaling on the back, and can infect dogs, cats, people, and rabbits. They can also be difficult to find on skin scrapings, and so trial treatment for cheyletiella is warranted if symptoms are consistent with infection. Treatment options are the same as for scabies mites, and all animals in the household have to be treated at the same time, or they will pass the mites back and forth. 3. Infections: Although the main reason for a pet’s itchy skin may be allergies or parasites, they often get secondary bacterial or yeast infections which can keep the itch going even if the underlying cause is treated. These infections can cause red, crusty, flaky skin, hair loss, pimples, and red bumps. Yeast infection can cause skin to look thickened and “elephantlike.” Diagnosis is made by the veterinarian with analysis of skin samples under the microscope. Skin infections should be treated with a 2-6 week course of appropriate oral antibiotics or antiyeast medication prescribed by a veterinarian. Medicated shampoos and conditioners can also be helpful.


Animals that have recurrent infections need to be screened for allergies or hormonal conditions and have the underlying cause identified and treated. In summary, although there are numerous causes of itching in pets, through appropriate diagnostics and treatments, or by referral of tough cases to a specialized veterinary dermatologist, your veterinarian can help your pet become a happier and more comfortable part of your family


Questions to Ask Your Veterinarian about Pet Dental Cleanings

We know you want the best for your pet and often pet owners are nervous about taking their pet for a veterinary dental cleaning because they are fearful about their pet being put under anesthesia for the procedure. First, we want to reassure pet owners that under the correct protocols, anesthesia is very safe and is far less dangerous than the periodontal disease that will develop without proper cleanings.

When preparing to take your pet for a veterinary dental cleaning, here are some questions you can ask your veterinarian to give you peace of mind about your pet’s safety and the care you can expect.

Questions about Anesthesia:

Proper equipment and monitoring ensures your pet’s safety during the anesthetic procedure.

  • Do you perform laboratory work for my pet prior to anesthesia?
    Laboratory work will be recommended by your veterinarian to evaluate your pet’s internal organ function prior to anesthesia.
  • Who performs and monitors the anesthesia process?
  • You should confirm that your pet is monitored under anesthesia by a trained veterinary technician who monitors blood pressure, blood oxygen saturation, end tidal carbon dioxide, electrocardiogram, respiratory rate and body temperature.  Intravenous fluids should be administered throughout the procedure to help maintain your pet’s blood pressure and provide intravenous access for additional drugs if they are needed. Your pet should be kept warm with warming blankets during the procedure. Your veterinarian should be happy to discuss every step of the process with you.
  • What is your full anesthesia protocol?
    You should confirm your pet’s blood pressure and blood oxygen are constantly monitored by a trained veterinary technician, that IV fluids are administered throughout the procedure and pets are kept warm with warming blankets during the procedure. Your veterinarian should be happy to discuss every step of the process with you.
  • Ask for the practice’s anesthetic safety record. 
AAHA certified veterinary practices are required to keep anesthesia safety records. You can ask about this record and a practice should be more than happy to share this information with you.

Questions about the dental procedure?.

  • Do you take radiographs as a standard practice for all cleanings?
    A comprehensive veterinary dental cleaning will include radiographs. This is the only way to identify other painful problems that may exist in your pet’s mouth under the gum, in the bone or involving the tooth root due to periodontal or endodontic disease.
  • Do you use localized nerve blocks?
    Local nerve blocks, in addition to pain medication administered prior to anesthesia, reduces the need for general anesthetic, improving the safety of the procedure and making your pet’s recovery faster and less painful.
  • What is your protocol if you identify a problem?
    You should ask your veterinarian how they handle disease that they find and if they will discuss the findings and treatment options with you immediately. You may also want to ask how they handle any complex issues they find such as broken teeth, bone loss or other problems. In many cases a specialist can save teeth with root canal procedures as opposed to extraction – keeping teeth intact when possible can prevent future dental problems to a pet.


2020 All images & content copyrighted by American Veterinary Dental Collage


FAQ’s about Pet Dental Cleanings

 How often should my pet have a dental cleaning?

Dogs and cats should have a veterinary dental cleaning annually starting at age two, or sooner if they have some other oral health problem identified earlier.

 Why does my pet’s breath smell so bad?

Bad breath is a sign of disease, often it may mean that oral disease is present in your pet’s mouth, not that their teeth are just dirty. Bad breath is often an indication of periodontal disease which lurks beneath the gums and can eat away at bone, oral tissue and tooth structure. Severe periodontal disease can also affect other organs, such as heart, liver and kidneys, as the disease progresses.

What is the difference between a pet dental cleaning at my vet or one at an anesthesia free dental clinic?

A veterinary dental cleaning involves a complete oral examination by a veterinarian, cleaning both above and below the gum line, and dental X-rays. An anesthesia free dental cleaning is a non-veterinary procedure where a pet is restrained awake, while the visible portion of some surfaces of the teeth are scaled (scraped with an instrument). This does not clean your pet’s teeth and leaves your pet at risk for a progression of the remaining oral disease and future dental disease and problems.

Is anesthesia for dental cleanings safe?

Using correct anesthetic protocols and monitoring by a dedicated trained anesthetist at a veterinary hospital, pet anesthesia is very safe.

Why are veterinary pet dental cleanings more costly than the anesthesia free procedures at my groomer?

Put simply, when it comes to the procedure alone, you get what you pay for. A veterinarian provides a professional service that requires a great deal of training and experience with the pet’s health in mind. There are certainly more costs involved in anesthesia, equipment, x-rays and trained staff, which all amount to your pet getting a higher quality of care and ultimately maintaining a healthy mouth. Over the long term, extensive dental disease as a result of a pet not having cleanings or having anesthesia free cleanings can become far more expensive.

Do cats and dogs need the same type of cleanings?

The simple answer is yes. The key thing to remember is that both cats and dogs need regular veterinary dental care. Overall each need the same components of care, however since they have unique health care concerns and anatomy, it’s important they are in the care of a veterinary doctor who is experienced and able to identify specific disease in different species, such as feline tooth resorption, feline stomatitis, or oral cancers.

2020 All images & content copyrighted by American Veterinary Dental Collage





Atopy or environmental allergies are quite common in dogs and cats. Environmental irritants may include pollens, molds, house dust mites, and even human dander. Some pets may have an allergic flare-up for only short periods in the spring and fall, while others show symptoms all year long.

Typical allergic signs in pets are scratching, face rubbing, obsessive licking of the feet, ear inflammation and infections, skin rash, pigmentation change and patchy hair loss. Allergies can also allow the skin and ears to become infected with bacteria or yeast. These secondary infections will then increase the overall “itch” level of the skin. Unfortunately we cannot usually permanently “cure” allergies, but we can control and treat the symptoms. Pets with a short allergy season can be treated with low doses of steroids, fatty acids, antihistamines, frequent bathing, and wipe downs to remove pollens from the skin. This may be all that’s needed to keep your pet comfortable.

Often times an antibiotic or anti-fungal agent will be added to combat a concurrent infection. Apoquel, Cytopoint, and Atopica (cyclosporine) are all non-steroidal options that can significantly ease your pet’s discomfort. These medications have been proven to be highly effective when used along with immunotherapy.

Pets who are seasonally allergic for longer periods may need intradermal allergy testing and immunotherapy or desensitization. This is the injection of allergens underneath the skin administered at home. Desensitization stimulates the T-lymphocyte suppressor cells, blocking the immune system, which is hyperactive in an allergic patient. Immunotherapy is highly effective in seventy five percent of treated pets.

Fifty percent of these pets respond to treatment in 3 to 6 months and twenty five percent of pets respond within 12 months. Most pets will need lifelong booster injections to continue immunotherapy. To begin immunotherapy, your pet must first be allergy tested. Testing is done by injecting different allergens common in your area under the skin and evaluating the reaction. Please do not hesitate to contact us if you have any other questions about your pet’s allergies or the treatments we can offer.

Stones in the urinary tract are common in dogs and cats. Even though dogs and cats do get kidney stones, it is bladder stones that cause more problems. The medical terms for bladder stones are urolithiasis or cystic calculi. We will use stone, calculi, and urolith synonymously in this page. The two most common calculi are calcium oxalate and struvite.

Stones can also occur in the kidneys, where they are called nephroliths. This page will limit its discussion to stones in the bladder.


There are several factor, usually working in combination that lead to urolith formation:

  • Mineral Crystals

Urine that is saturated with excess amount of certain minerals is prone to form bladder stones. These minerals commonly include magnesium, phosphorous, calcium, and ammonia. Most stones consist of an organic matrix of protein surrounded by crystalline minerals.

Diet can have a major impact here, and is one of the primary methods we use to treat and prevent uroliths.

  • Urine pH

pH is an indicator of acidity by measuring the hydrogen ion concentration. A pH of 7 is neutral. Below 7 is acidic, above 7 is alkaline. As a general rule, dog and cats tend to have an acidic urine. Some uroliths have a propensity to form in acidic urine, while others tend to form in alkaline urine. Urine pH needs to be measure immediately upon voiding from the bladder for it to be accurate.

  • Bacteria

Some uroliths form due to the presence of bacteria in the urine, so control of these bacteria is important. Bacteria are diagnosed by culturing the urine during a sterile urinalysis, or by culturing the inside of a stone after surgical removal. Normal urine is sterile, so any bacteria cultured from the urine is abnormal. When bacteria are cultured a pet has a urinary tract infection (UTI) and needs antibiotics. Common bacteria in UTI’s include E. coli, Staph. spp., and Proteus.

If any bacteria are cultured in the urine our laboratory will test numerous antibiotics to determine which are the best ones to eliminate the bacteria. This is called sensitivity testing. We also do a test called MIC (Minimum Inhibitory Concentration) to let us know the best antibiotic to use and the best dose of that antibiotic.

  • Diseases

Liver shunts are an abnormality of blood flow to the liver. Blood that would normally flow through the liver now bypasses the liver. One of the many consequences of this disease, called Portosystemic shunts (PSS), is the formation of ammonium urate bladder stones.

  • Medications

Medications can predispose pets to forming bladder stones. Sometimes they do this by increasing the calcium level in the urine. Medications that increase or decrease the pH of the urine can also set the stage for stone formation. Some medications can actually cause formation of stones when used for long periods of time. The following list includes some of these medications:

  • Lasix
  • Cortisone
  • Ascorbic Acid (Vitamin C)
  • Sulfa medications
  • Tetracycline’s

Predisposing causes of bladder stones include pets that are not drinking enough or are not allowed to urinate frequently. Bacteria and stone forming chemicals stagnate in the urinary bladder and increase the chance of a stone forming. Mechanical flushing of the bladder, in the form of normal and frequent urination, will prevent this.

Always make sure your pet has access to fresh water, changed several times per day, and the ability to urinate frequently. As a matter of fact, if you feed dry food you should be giving more than one cup of water per cup of dry food. An easy way to get around this important requirement for water is not to feed dry food at all. Your pet’s urine should be clear, with no odor or color, and your pet should urinate every few hours. Sometimes these common sense suggestions are so obvious that we tend to forget about their importance.

Typical symptoms of bladder stones:

  • Straining to urinate (stranguria)
  • Blood in the urine (hematuria)
  • Urinating small amounts frequently (pollakiuria)
  • Often times there are no symptoms at all, and the problem is discovered on routine abdominal palpation or radiography.

There might also be excess urination (polyuria), pain in the rear quarters, reluctance to jump or play, or even lethargy and a poor appetite. Some pets can have bladder stones without any apparent symptoms at all!

The bladder stones can pass out of the bladder and lodge in the urethra, especially in male dogs due to the smaller diameter of their urethra. In some cases they can block the flow of urine, which is a medical emergency. This can cause problems with the kidneys, leading to the buildup of toxic waste products. Common areas for these urethral obstructions are the ischial arch near the pelvis and further down the urethra at the os penis. Both of these areas have small diameter urethras that do not expand to allow passage of a stone. You will learn more about this later.



Urine analysis                                                                                                                                                           Culture                                                                                                                                                                   Radiography                                                                                                                                                            Ultrasound

There are many different types of bladder stones. Some of the most common ones include:

    • Struvite

This urolith is diagnosed in almost half the cases of bladder stones. It is also called MAP (Magnesium-ammonium-Phosphate), or triple phosphate. Struvite uroliths come in many different shapes and sizes, are radiodense, and form in an alkaline urine.

It is the predominant stone type in female dogs of all breeds except Dalmatians. This is because of the high association of struvite crystals with urinary tract infections, which are more common in female dogs. If a female dog gets a bladder stone, 80% of the time it is struvite because of this association. Dogs under a year of age, no matter what  sex, get struvite as the most common bladder stone for this same reason. Miniature Schnauzers are the most commonly affected breed, along with bichon frise, cocker spaniels, and miniature poodles.

Canine  urine is commonly supersaturated with struvite crystals due to the high protein and mineral content of current diets. This excess of these crystals in the urine, stored in the urinary bladder, combines with bacteria to set the stage from the formation of bladder stones (uroliths). Bacteria that are commonly implicated include Staphlycoccus, Enterococcus, and Mycoplasma.  These bacteria increase the amount of organic debris available for crystallization.

These bacteria also produce urease as a by product of their metabolism. They  split the urea in urine into ammonia and carbon dioxide. As this ammonia is broken down it changes the pH of the urine from its usual acid (pH less than 7) to alkaline (PH > than 7). High urine ammonia concentrations in the urinary bladder can damage the glycosaminoglycans that help prevent the bacteria from adhering to the bladder mucosa (interior lining of the bladder). When we treat for this disease we address these issues.

What does all of this mean?

Excess struvite crystals in the urine  set the stage for the formation of the urolith.

Urinary Tract Infection (UTI)- some bacteria produce a byproduct called urease. Urease will increase the pH of the urine and promote ammonium in the urine.

The formation of an alkaline (pH greater that 7.0) urine from the diet, or from urease producing bacteria, will cause the struvite crystals to precipitate out of solution and begin the formation of a urolith.

Urine that stays in the bladder longer than usual gives the struvite crystals further opportunity to precipitate out of solution and form a urolith.

    • Cats commonly form struvite bladder stones in the absence of a urinary tract infection. This is probably because cat urine is more concentrated (higher specific gravity) than dogs, so the urine is more saturated (we call this supersaturation) with magnesium, ammonium, and phosphate. This is especially true when the urine pH is highly alkaline, which can occur with the use of some drugs, in certain diets, and when the tubules of the kidney are diseases. If there is a bacteria involved it is usually Staphlycoccus.

Calcium Oxalate

This is the second most prevalent type of urolith after struvite, making up around 30-50% of the uroliths we diagnose, especially in male dogs of all species, except Dalmatians. They come in two versions; the monohydrate and the dihydrate. Sometimes the two are found together, sometimes they are found with other uroliths like calcium phosphate, struvite, or ammonia irate. They show up well on a radiograph. They form in an acidic or neutral urine (pH is 7 or just slightly less). Recurrence is common, so diligence on your part is needed to prevent recurrence.
Feeding an older pet with Kidney problems a food like Hills Prescription Diet K/D may slow or prevent further growth.
If this stone is small and not causing any apparent problem it can be monitored. Some pets will have high calcium (hypercalcemia) in the bloodstream.

Several predisposing factors work together to increase the chance of this urolith forming:

Increased calcium in the bloodstream (hypercalcemia)

Increased calcium in the urine (hypercalciuria) with no hypercalcemia

Concurrent Cushing’s disease

Use of cortisone for skin allergies or Addison’s (hypoadrenocorticism) disease.

These tend to occur in neutered middle aged cats and older cats, especially Burmese, Himalayan, and Persian breeds. One of the predisposing conditions might be an increased calcium level in the bloodstream. These uroliths tend to form in an acidic urine.

This is a problem most commonly in older male dogs. It is suspected that there is a correlation with hormone changes that occur as a pet ages. Several breeds are prone:

Miniature Schnauzer

Lhasa apso

Yorkshire terrier

Bichon Frise

Shih Tzu

Miniature poodle

Urate and Ammonium Urate

This is a common urolith found in Dalmatians around middle age, with males affected much more often than females. This is because they metabolize protein differently in the liver, with the end result being uric acid buildup in the urine. In addition to their high prevalence in Dalmatians, they are found in Bulldogs and Yorkshire terriers.
There does not seem to be a connection with a urinary tract infection, and they tend to form in an acidic urine.
Urate stones are radiolucent. If they get large or covered with other minerals they might become radiopaque. Urate calculi tend to be small and occur as several stones. These stones usually form in the bladder, and when passed through the urethra, can become lodged.



Most cases of struvite are treated surgically. The procedure is explained below.

Struvite bladder stones can also be be treated medically with a food called Hills S/D. The mechanism involves creating a urine that is undersaturated with the crystals that caused the struvite urolith to form in the first place. This undersaturation literally cause the urolith to dissolve in the urine, and then get urinated out. It is a slow and gradual process, although most pets get relief from straining and blood in the urine soon after starting this diet.

S/D has several modifications in its ingredients to set up this undersaturated urine. Its reduced in protein, so there is less ammonia buildup in the bladder from bacteria. Magnesium and phosphorous are restricted also. With less contents of the minerals that form the struvite urolith (magnesium, ammonia, and phosphorous- MAP) the urolith starts dissolving.

S/D also has an increased amount of salt (sodium chloride). This promotes drinking and urination and literally helps flush the struvite crystals out of the bladder. It also changes the pH to a more acidic state, which further makes the struvite stone dissolve.

The rate of dissolution is proportional to the surface area of the stone expose to this now undersaturated urine and the control of the urinary tract infection in dogs.  Feline struvite stones tend to dissolve faster than canine because bacteria are not implicated.


We can measure the size of a stone with our digital x-ray to make sure it is getting smaller early in the process of dissolving it

S/D must be the only food fed for it to work. We can monitor whether or not an owner is doing this by looking at the pH of the urine along with the specific gravity of the urine. also, the BUN (blood urea nitrogen) of a pet on S/D should be lower than normal.

We have clues from other diagnostic tests to help decide if a urolith found in the urinary bladder on a radiograph is truly struvite. The urinalysis gives us an idea of the composition of the urolith by looking at the crystals in the sediment. The pH of the urine will be alkaline. Also, the presence of bacteria on a culture in a breed that is prone to struvite uroliths is also a strong indication.

If bacteria are found on a urine culture in dogs then antibiotics must be used simultaneously while a pet is on S/D. It must be the correct antibiotic, so the importance of the urine culture is obvious. Both S/D and antibiotics are used for one month after the stone is no longer visible on a radiograph. If there is a persistent urinary tract infection we might use a urease inhibitor called acetohydroxamic acid. Urinary acidifiers are usually not used.

If the urolith is still present after 2 months of S/D and antibiotics, then surgery should be performed. Most pets need to be fed S/D for 4-6 months for complete resolution. It should be fed for an addition 30 days after there is no longer any stone based on a radiograph.

S/D is restricted in protein, so it is not a complete diet for long term use in dogs. It also should not be used pregnant dogs, lactating dogs, ground dogs, and after surgery due to this protein restriction. While on S/D your dog’s blood should be monitored to ensure there are no side effects of the restricted protein.

Due to the high salt (sodium chloride) it should not be used in dogs with congestive heart failure and hypertension.

S/D diet tends to work faster in cats because bacteria are not usually involved. S/D should also be fed for 30 days after there is no more evidence of a stone in the bladder when radiographed. Feline S/D is not protein restricted, so it can be used for the rest of your cat’s life.

Calcium Oxalate

The only treatment for these uroliths is surgical removal. This is the easy part, its preventing their recurrence that is difficult. The protocol in how to do this was shown earlier.


If there is no PSS these uroliths can sometimes be handled medically also. A food called Hills U/D should be used. It is low in purines and has restricted protein. A medication called allopurinol is given which helps minimize the amount of uric acid produced in the urine. Potassium citrate is also used to make the urine less acidic, although this might occur with the use of U/D alone. Adding salt to the diet or mixing water with the food will also promote urination of the urate crystals. Recurrence is common, so this diet needs to be used for the life of your pet, especially in Dalmatians. We will talk more about this later in the prevention section.

Surgical Treatment

Many bladder stones are treated surgically.


Medical dissolution or surgical removal of the bladder stone is the first step in the process. The next, and just as important step, is the prevention of the stone’s recurrence. Some of these stones will require a diet change only, while others might require long term medication. Some breeds are predisposed to forming stones in spite of what we do to prevent them. Our doctors will set up a specific protocol for your pet based on the breed and type of stone removed.

Long term follow up is important. Your pet will have to return periodically to recheck a urinalysis, culture the urine for bacteria, and x-ray the bladder. Many stones recur because owners forget the importance of long term prevention.

At all times make sure your pet has access to fresh water and the ability to go to the bathroom. This treatment alone will go a long way to prevent recurrence. Giving your pet food that has more moisture will increase the flow of water through the urinary system and minimize crystal formation in the bladder. As a general rule, we do not recommend adding salt (sodium chloride) to the food to get your pet to drink more water because it might promote calcium formation in the urine, thus setting the stage for a stone to form. Your doctor will let you know if this applies in your case.


Pets that have struvite urolithiasis, whether treated surgically or medically, have a chance of recurrence if not monitored carefully. If the urine is alkaline on a urinalysis it should be cultured to check for bacteria. Antibiotics are indicated if the culture is positive. If the pH stays alkaline in spite of antibiotic therapy, then Hills C/D should be used. It will help maintain an acidic urine, and has some mild restrictions in protein and minerals. As a general rule, we recommend C/D for all pets that have had struvite crystals. It can be used on a long term basis, and is helpful in preventing FLUTD in cats. S/D can also be used long term in cats.

If your dog gets recurring urinary tract infections, thus predisposing it to a struvite bladder stone, it is important to examine it for abnormal anatomy of the vulva, for obesity, and problems with the urethral sphincter.

Calcium Oxalate

Recurrence rates with this urolith are high, so a long term plan and commitment to sticking with it are important.

Baseline data consisting or radiographs, urinalysis, urine culture, and blood panel needs to be obtained. Particular attention is paid to the blood calcium level.

A diet with reduced quantities of protein, calcium, and sodium, that also does not make an acidic urine, is the ideal diet to feed. Too much of a reduction in these nutrients can be detrimental, so no supplements should be added. The primary diet in the cat that accomplishes this ideal is Hills Prescription Diet K/D. In dogs, K/D, W/D, and U/D are used. The use of U/D might preclude the use of potassium citrate as long as there are not calcium oxalate crystals in the urine and the pH is alkaline. There is a C/D that treats calcium oxalate uroliths in cats.

Certain foods that are high in oxalates or calcium, or foods that increase calcium levels, must be avoided. They include high protein foods, spinach, rhubarb, parsley, milk products, and table salt.

When we diagnose a calcium oxalate stone we will check the calcium level in the bloodstream to make sure it is not abnormally high. This normal calcium level was from the dog above that had the surgery to remove the calcium oxalate stones from its bladder and urethra.

Vitamin C and D, along with drugs that make the urine more acidic, should not be added to the diet. Cortisone also should be used cautiously because it increases the calcium level in the urine.

Potassium citrate will inhibit calcium oxalate crystal formation and keep the pH of the urine in the ideal range. We will use this if U/D does not keep the urine alkaline.

After surgery your pet should return in 2 weeks for a urinalysis. If there are calcium oxalate crystals in the urine we will add potassium citrate as per above. If there are no crystals we will not need to do a recheck for 3 months. At this 3 month recheck of the urine we will also re-radiograph the bladder and check a blood panel noting the calcium level.

Two weeks after surgery this is the urine sample of the dog with the above stones. This is what we want to see- no crystals, no bacteria, and an alkaline pH.

Ammonium Urate and Urate – Medical care for Dalmatians after surgery includes:

  1. Increasing water consumption so the specific gravity of the urine is near 1.018. adding water to dry food, feeding more canned food, and adding encapsulated light salt (KCl) all will help.
  2. Feeding a diet low in purines. Diets low in purines include the Hills Prescription Diets K/D or U/D dry and U/D canned.
  3. Increasing the pH of the urine to 7.0-7.5. The above diets might accomplish this pH. If not, adding oral potassium citrate to the diet will help.
  4. Controlling urinary tract infections, if any, by performing urine culture and sensitivity tests every 3-6 months, and using antibiotics on a long term basis if needed.
  5. Adding allopurinol to the diet to prevent the conversion of purine to uric acid.This therapy needs to be followed diligently for the life of your Dalmatian.

Medical care for cats and non-Dalmatian dogs after surgery is similar. Most of these uroliths are caused by a PSS, thus surgery to correct the liver problem will help prevent the recurrence of these stones in the bladder. In some PSS’s the liver problem cannot be completely resolved, adding to the risk of formation of these bladder stones in the future. Long term therapy is similar to Dalmatians:

  1. Increasing water consumption so the specific gravity of the urine is near 1.018 for dogs and 1.025 for cats. adding water to dry food, feeding more canned food, and adding encapsulated light salt (KCl) all will help.
  2. Feeding a diet low in purines for dogs. Diets low in purines include the Hills Prescription Diets K/D or U/D dry and U/D canned. For cats feed diets that do not acidify the urine, which unfortunately, many do to prevent FLUTD.
  3. Increasing the pH of the urine to 7.0-7.5. The above diets might accomplish this pH. If not, adding oral potassium citrate to the diet will help.
  4. Controlling urinary tract infections by performing urine culture and sensitivity tests every 3-6 months, and using antibiotics on a long term basis if needed.

Credit to Long beach animal hospital




Topical ear medications are often necessary to adequately treat inflammatory or infectious ear conditions. Some dogs will tolerate the administration of liquids or ointments into their ears, while others will not.

Remember that your dog’s ear condition may be painful, and that even a normally gentle and passive dog may respond by struggling, growling, biting, or scratching. Until the medication begins to control the problem and ease the discomfort, you may need to muzzle your dog for this procedure.

Make sure you carefully read the drug label and understand the prescription instructions before following the step-by-step procedure below:

If the medication is refrigerated, you may be able to warm it up by placing the container in a bowl of warm water for a few minutes. Be sure to ask your veterinarian if this is acceptable before warming any medication. DO NOT MICROWAVE THE MEDICATION.

Hold the medication in your dominant hand. Draw up the liquid into the dropper or prepare the squeeze bottle as directed.

Gently pull the flap of the ear up and slightly back using your other hand.

Apply the prescribed number of drops into the ear canal, while continuing to hold the ear flap up.

Rub the base of the ear against the head in a circular motion. Be cautious and gentle as your dog may object to this procedure. You should hear a “squishing” sound as you massage the medication deep into the ear canal.

Release the ear and let your dog shake its head. If the medication contains a wax solvent, it will dissolve the debris, which your pet will shake out of the ear. You may gently wipe away any accumulated debris from the ear flap with a tissue or ball of cotton.

Make sure you give your dog plenty of praise throughout the procedure and offer a treat during and after giving the medication. This will make the experience more positive and make it easier to give the medication the next time.

Remember that your dog’s ear(s) may be very painful and that your dog may respond by scratching or biting. Use caution and patience when treating your dog’s ear(s).


About CVC

Chappelle Veterinary Clinic is a full service Veterinary Clinic which offers a wide range of veterinary care for cats and dogs, including routine exams, vaccinations, preventative care, diagnostics, surgery, spay and neuter, wellness services, dental cleaning, emergency and more.

Working Hours

Monday 8:00 AM – 6:00 PM
Tuesday 12:00 PM – 9:00 PM
Wednesday 8:00 AM – 9:00 PM
Thursday 8:00 AM – 6:00 PM
Friday 8:00 AM – 6:00 PM
Saturday 8:00 AM – 3:00 PM
Sunday Closed

Contact us

14128 28 Avenue SWEdmonton, AB T6W 3Y9

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