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Learn about Common Pet Health Conditions

Knowing about your pet’s health is important to keep them living a full life. Learn more about common conditions that may be currently afflicting your pet.

Idiopathic Vestibular Disease

Adapted from (Wendy C. Brooks, DVM, DABVP) and Disorders of the Vestibular System (Laurie K. Pearce, DVM)

The vestibular system is the part of the middle ear that is responsible for maintaining balance and telling our brain where the body is positioned. Vestibular system disorders cause a severe sense of “vertigo” and can cause signs such as loss of coordination, falling over, trouble standing, head tilt, and rapid side-to-side eye movements (called nystagmus). Middle ear infections, tumors, polyps, and head trauma are a few of the conditions that can cause these signs. However, the most common cause of these signs in middle aged to older dogs is Idiopathic Vestibular Disease (also known as Old Dog Vestibular Syndrome).

This can be a frightening disorder that often seems to come on suddenly with no apparent cause. In addition to the signs described above, some dogs with Idiopathic Vestibular Disease also experience:

  • Circling
  • Inability to walk or even stand
  • Drooling
  • Vomiting
  • Crying or whining

Owners may think that their pet is having a stroke due to the suddenness and severity of the clinical signs.

Unfortunately, the cause of this disease is still unknown. The good news is that the condition nearly always resolves over time. Most dogs improve significantly within 72 hours and many are back to normal within one to two weeks. Rarely, some dogs have a residual head tilt even after all other signs have resolved.

Treatment for this depends on how severely the pet is affected. If the dog is severely affected (vomiting, not eating), he or she may need hospitalization and intravenous fluids until the condition resolves. If your dog is able to eat and drink, then he or she will probably not to be hospitalized. The veterinarian may prescribe medication to help with the nausea that can accompany this condition.

Idiopathic Vestibular Disease can be a frustrating condition, but luckily, the problem is usually short lived and has a high recovery rate. More information on this condition is available at and

Frequently Asked Questions about The Cranial Cruciate Ligament

(Adapted from an article on by Wendy C. Brooks, DVM, DABVP)

What is the cranial cruciate ligament?

The knee consists of the femur (or thighbone), the tibia below the femur, and the patella (or kneecap). Chunks of cartilage called menisci fit between the femur and tibia like cushions, and an assortment of ligaments hold everything together.

There are two ligaments that cross inside the knee joint: the cranial cruciate ligament and the caudal cruciate ligament. The cranial cruciate ligament (the one most commonly injured in dogs) prevents the tibia from slipping forward out from under the femur.

How does this injury happen?

A torn cruciate ligament is the most common knee injury of dogs. Young dogs that injure their cranial cruciate ligament usually do so during intense exercise or rough play. This is usually a sudden lameness in a young, large breed dog.

Alternatively, an older dog may have weakened ligaments and may slowly stretch or partially tear them over time. The partial tear may be detected, or the problem may not become apparent until the ligament tears completely. With this injury, just stepping down of the bed or a small jump may be all it takes to break the ligament. The lameness may seem sudden, but on further examination, there may be signs of more chronic joint disease. In some cases, the lameness may develop as a gradual problem.

Larger, overweight dogs that tear one cruciate ligament frequently tear the same ligament in the other knee within a year or two, so an owner should be prepared for possible surgery on the other knee in the future.

How can you tell when the cranial cruciate ligament is injured?

This injury usually involves a rear leg suddenly so sore that the dog doesn’t want to bear his/her full weight on the leg. If left alone, the lameness may appear to improve, but the knee will be notably swollen and arthritis will set in. Either dogs may be brought to their veterinarian in the acute stage (shortly after the injury) or in the chronic stage (weeks or months later, after arthritis has set in).

The key to diagnosis of a torn cruciate ligament is demonstration of an abnormal knee motion called a drawer sign. However, it is not unusual for pets to be tense or frightened at the vet’s office, and tense muscles can temporarily stabilize the knee and prevent this type of movement. Often sedation is needed to get a good evaluation of the knee.

What type of surgery can be done to repair this injury?

Tibial Plateau Leveling Osteotomy (TPLO) — With this surgery, the tibia is cut and rotated in such a manner that the natural weight-bearing forces of the leg stabilize the knee joint. Surgery requires 8 weeks of exercise restriction afterwards (no running or jumping, outside on a short leash only, etc.). Full function is generally achieved 3-4 months after surgery.

At this time, the TPLO procedure is considered the best way to repair a torn cranial cruciate ligament, especially in larger dogs. This surgery is complex, involves specialized training and equipment, and typically costs twice as much as the extra-capsular method described below.

Extra-Capsular Repair — In this procedure, a suture or wire is placed around the knee joint in a strategic fashion in order to stabilize the joint. The fixation will eventually wear out and break, but at this point the dog’s own healed tissue will hold the knee. As with the TPLO procedure, 8 weeks of exercise restriction are required.

What happens if the torn cruciate ligament is not surgically repaired?

Without an intact cranial cruciate ligament, the knee is unstable. Abnormal wear develops between the bones and cartilage, and the joint begins to develop degenerative changes. Bone spurs called osteophytes develop, and the result is chronic pain and loss of joint mobility. This process can be stopped by surgery, but cannot be reversed.

Anal Sac Impaction

What are anal sacs?

The anal sacs are two small sac structures located on either side of the anal opening of dogs and cats. Glands located inside these sacs produce a liquid with a very strong odor that some mammals use to mark their territory.

What are the signs that my pet may have an anal sac problem?

Pets may scoot their anal area on the floor, lick or chew the area, or act painful around their backside. Sometimes they appear constipated and strain or cry while trying to have a bowel movement. Owners may also notice the strong odor of the anal sac liquid, which is sometimes described as a “rotting” or “fishy” smell. This condition can be uncomfortable and unfortunate.

What causes anal sac impactions?

Normally, every time an animal has a bowel movement the anal sac empties itself easily without any discomfort to the animal. In some pets, however, the sacs don’t empty properly and the fluid that collects in the sac builds up, causing pressure, and/or discomfort in the anal area. No one knows for sure why this happens in some pets, but it seems more common in pets that are overweight and in pets that suffer from allergies.

Is this a serious condition?

In most cases, anal sac impaction is not considered serious, but it can be painful for the pet. Sometimes the anal sacs become infected and may become so full of infected material that they rupture. If this happens, the area will need to be cleaned and the pet may need to receive antibiotics.

What is the treatment for anal sac impaction?

Most pets respond well to regular anal sac expression, meaning the veterinarian or veterinary assistant manually squeezes the fluid out of the anal sacs to avoid impaction, infection, and rupture. Depending on the pet, this may need to be done every 4-6 weeks. While not a pleasant experience for the pet, it is a quick and relatively simple procedure. Weight loss and extra fiber in the diet (e.g. canned pumpkin) may help prevent future impactions in some pets.

In severe cases where regular anal sac expression doesn’t help or in pets with chronic anal sac infections, additional treatment options include flushing the anal sacs or even surgical removal of the anal sacs. Both procedures require the pet to be under general anesthesia. While the surgery can be done at most general veterinary practices, there is some risk of nerve damage in the anal area that may result in fecal incontinence. Treat this problem sooner rather than waiting until it becomes severe.

Where can I get more information about this problem?

The website contains illustrations of where the anal sacs are located and has further discussion regarding surgical removal of the anal sacs.

Arthritis in Dogs

Arthritis is a common ailment in older dogs. The following list of supplements, medications, and lifestyle changes can do much to improve your pet’s quality of life if he or she is experiencing the aches and pains associated with arthritis.

Joint Supplements

Joint supplements are designed to slow down the progression of arthritis. Several options vary in effectiveness, price, and method of transmission. The three most common products for this are described below.

Adequan is an FDA-approved treatment for arthritis in dogs. It contains polysulfated glycosaminoglycans (PSGAGs), which help the cartilage in joints produce more lubricating fluid, which makes joint movements less painful. Adequan is administered as an injection, either in the muscle or under the skin. The injections are given twice a week for four weeks, then once every 1-2 weeks, and then tapered to the lowest effective dose.

Cosequin is a pill that contains glucosamine and chondroitin sulfate, nutrients that cartilage cells use to repair themselves. Roughly, half of dogs with arthritis seem to be in less pain when they regularly take glucosamine/chondroitin sulfate supplements. Cosequin is specifically formulated for dogs and is the brand currently recommended by veterinary pain management specialists. This recommendation is largely because the company that makes Cosequin has a good quality control record (see below).

Over-the-counter (OTC) glucosamine products are another option for arthritic dogs. Although this is the least expensive option, OTC products can vary in their effectiveness. This is thought to be due to the wide range of quality control. There is no official oversight of ingredients and concentrations in OTC supplements, and there is no guarantee that each pill contains what it says on the bottle.

No matter what product is used, there are certain dogs who don’t seem to respond to supplements alone. If your dog shows no improvement after taking a supplement at an appropriate dose consistently for 6 weeks, it’s likely that your dog is a non-responder and giving additional joint supplements is not of any benefit.

Non-Steroidal Anti-Inflammatory Drugs (Nsaids)

These can be used either intermittently (e.g. after strenuous exercise) or daily (e.g. when a dog has difficulty walking) to relieve the pain associated with arthritis. We recommend Rimadyl, but other types of NSAIDs include Deramaxx, Metacam, or Previcox. These medications are very effective at relieving arthritis pain, but do nothing to address the underlying cause (i.e. joint damage). This means that your pet may feel better, but his or her arthritis will continue to progress.

Although we prefer to try the other options listed above first, some pets need NSAIDs in order to have an acceptable, pain-free quality of life. Dogs who need to stay on Rimadyl or any other NSAID long term should have periodic bloodwork drawn to evaluate kidney and liver function as these organs are involved in metabolizing the drug.

What Not to Give Your Arthritic Dog

In the past, owners gave their dogs aspirin for minor aches and pains. However, recent research has shown that aspirin is consistently associated with gastric (stomach) bleeding and ulceration in dogs. For this reason, we recommend safer options, such as Rimadyl.

Never give your dog ibuprofen (Motrin, Advil), naproxen (Aleve), or acetaminophen (Tylenol) as these can be toxic to dogs. Do not give two anti-inflammatories simultaneously for pet health conditions, such as Rimadyl and aspirin or Rimadyl and prednisone, as this can cause severe stomach and intestinal damage.

Other Ways to Help Your Arthritic Dog

Weight Loss: Excess weight places extra strain on joints and makes in more difficult for your pet to move comfortably. Even losing five pounds can significantly decrease the strain placed on painful joints.

Exercise: Regular, low-impact exercise (such as leash walks or swimming) is excellent therapy for arthritic dogs. We recommend daily exercise that is not so strenuous as to cause limping. Multiple short walks each day may be better than one long walk. Avoid any activity that involves sudden stops, starts, and turns, such as playing fetch.

Avoid Slippery Surfaces: Slippery floors can be difficult for arthritic dogs to manage. Consider putting down carpet runners or some other type of non-skin rug on slick floors.

Avoid Stairs: Stairs can also be difficult for arthritic dogs. If possible, arrange your dog’s food, water, and bed on one floor so he or she doesn’t have to climb stairs as often. Another option is to arrange a downstairs sleeping/eating/drinking area for the daytime and an upstairs sleeping/eating/drinking area for the nighttime.

Physical Therapy: There are a growing number of physical therapy facilities in Colorado, including locations in Fort Collins, Boulder, Lafayette, and Denver. These facilities provide hydrotherapy, massage, and other treatments, all of which are designed to improve joint mobility and comfort. If you are interested in learning more about physical therapy in our area, please ask the veterinarian about local facilities.

Ear Hematoma

(Adapted from an article on by Wendy C. Brooks, DVM, DABVP)

What is an ear hematoma?

Ear hematomas occur when overzealous head shaking or scratching breaks a blood vessel in the ear flap, which may partially or completely swell with blood. The earflap feels fluctuant and fluid-filled, somewhat like a water balloon.

The swelling may be so large that the opening of the ear canal is obstructed, and the extra weight of the ear may be uncomfortable for the pet.

This condition is more common in dogs, but can occur in cats as well.

Why do ear hematomas happen in the first place?

Sometimes ear hematomas develop after trauma to the ear (such as during a fight with another animal), but more commonly the head shaking that causes an ear hematoma is secondary to pain or irritation associated with an underlying ear problem (such as an ear infection). However, some pets that develop ear hematomas have no evidence of previous trauma or underlying ear problems.

If there is evidence of an ear infection, this infection must be treated along with the hematoma. This usually involves microscopic examination of an ear swab by your veterinarian followed by daily ear cleaning and medications.

Will this condition resolve?

If left alone, an ear hematoma will eventually resolve over time as long as the pet does not continue to shake or scratch his/her ear. The fluid will be re-absorbed back into the body and the earflap will again the flat.

There is usually some scarring associated with this process, and the ear is often more thick or “crinkled” than before the hematoma occurred.

It can take several months for a large hematoma to resolve, which may be uncomfortable for the pet.

Can’t we just drain the fluid?

Unfortunately, aspiration (using a needle and syringe to remove the fluid) doesn’t entirely resolve the hematoma. The problem is that a space is left behind when the fluid is drained, and this space readily refills with more fluid. Aspiration usually yields only temporary results.

How else can we treat an ear hematoma?

The only effective way to treat an ear hematoma (other than letting it resolve over time) is surgery. An incision is made in the earflap, the hematoma is drained, and multiple sutures are placed in the hematoma space to prevent the ear from refilling with fluid.

Even with surgery, there is still the possibility for some scarring and thickening of the ear.

Discoid Lupus Erythematosus (DLE)

The Basics
  • DLE is one of the most common immune-mediated skin diseases.
  • This condition predominantly involves the top of the nose, the face, the ears, and the mucous membranes; rarely can it involve other areas, such as the feet or genitalia.
  • Predisposed breeds include Siberian huskies, Alaska malamutes, Akitas, German shepherds, Shetland sheepdogs, collies, chow chows, and their crosses.
What does DLE look like?
  • The signs of DLE usually start with de-pigmentation (lightening in color) of the nose and/or lips.
  • De-pigmentation progresses to hair loss, the formation of crusts, and ulceration or bleeding.
  • Tissue loss and scarring can occur in severe cases, especially if DLE is left untreated.
What causes DLE?
  • The exact cause is unknown, but involves the pet’s own immune system reacting to certain proteins in the skin.
  • A genetic predisposition is likely, meaning parents can pass the trait to their offspring.
How is DLE diagnosed?
  • The only way to definitively diagnose DLE is with a skin biopsy, which may require sedation or general anesthesia.
How is DLE treated?
  • The standard treatment involves two oral medications, tetracycline and niacinamide, which must be given 3 times daily.
  • If response to these medications is poor, alternative medications include a newer topical ointment called tacrolimus or oral drugs that suppress the immune system, such as prednisone or azathioprine.
  • No matter what medications are used, treatment is lifelong.
What else can I do to help my pet?
  • There is a direct link between the amount of sunlight that a pet is exposed to and the worsening of DLE. For this reason, susceptible animals should avoid direct sunlight, especially during the peak hours of 10 am to 4 pm. This also includes “sunbathing” in patches of sunlight indoors.
  • Some veterinary dermatologists also recommend supplementing oral vitamin E, although vitamin E alone does not control the disease.
  • Because of the suspected inherited nature of this condition, affected animals should not be used for breeding.
What is the outlook, or prognosis, for DLE?
  • Fortunately, DLE is not a life-threatening disorder.
  • Possible complications, especially if DLE is left untreated, include bleeding of traumatized skin, scarring, and/or secondary infection.

Cushing’s Disease

(Adapted from an article on by Wendy C. Brooks, DVM, DABVP)

What is Cushing’s disease?

Cushing’s disease (also known as hyperadrenocorticism) is a disorder caused by excessive production of cortisol, a hormone made by the adrenal glands. Cortisol is normally released in times of stress when it helps the body prepare of a “fight or flight” situation. It puts the body in a state of “breakdown,” so that stored resources can be mobilized and used quickly. If the body is exposed to this hormone most of the time instead of only during short stressful periods, this state of break down becomes debilitating.

There are two types of Cushing’s disease: pituitary-dependent and adrenal-dependent. In the normal body, the pituitary gland (located at the base of the brain) detects when cortisol levels in the blood are low. In response, the pituitary secretes a chemical that causes the adrenal gland to release more cortisol. When the pituitary gland detects that cortisol levels are again appropriate, it stops its stimulatory message. You can think of the pituitary gland as a sort of “thermostat” for cortisol control.

Pituitary-Dependent Cushing’s Disease

This type accounts for 85% of dogs with Cushing’s disease. A tumor, generally microscopic and benign, develops in the pituitary gland. This tumor over-produces its stimulatory message, leading to enlargement of both adrenal glands and a subsequent over-production of cortisol.

Although benign, occasionally these tumors grow large enough to put pressure on the brain. In these cases, neurologic signs may be observed, usually involving changes in behavior.

Adrenal-Dependent Cushing’s Disease

In 15% of dogs with Cushing’s disease, an adrenal tumor is directly over-producing cortisol.

Half of these patients will have benign tumors and half will have malignant tumors, meaning there is the potential for the tumor to spread to other parts of the body.

What does Cushing’s disease look like?

The clinical signs associated with Cushing’s disease usually come on very gradually and may be written off as part of the normal aging process. These signs may include some or all of the following:

  • Drinking and urinating excessively
  • Increased or ravenous appetite
  • Pot-bellied appearance
  • Excessive panting
  • Muscle weakness
  • Skin disease, including hair loss or hair that doesn’t grow back after clipping
  • Thick, wrinkled skin with poor wound healing
  • Easy bruising
  • Darkening of the skin
  • Persistent or recurring skin infections
How do you test for Cushing’s disease?

Cushing’s disease can be challenging to diagnose in some pets. Routine testing of blood and urine does not definitively diagnose Cushing’s disease, but when combined with the symptoms of Cushing’s disease described above, routine blood and/or urine tests can provide ‘clues’ that this disease may be present. Definitive diagnosis may involve a series of tests, including additional bloodwork, urine tests, and/or imaging (such as radiographs, ultrasound, MRI, or CT scan).

More specific tests for Cushing’s disease include the following:

ACTH Stimulation Test: ACTH (or adrenocorticotropic hormone) is the hormone produced by the pituitary gland that tells the adrenal glands to release cortisol. This test involves a baseline blood sample to measure cortisol levels, a dose of injectable ACTH, and then a second blood sample drawn 1-2 hours later. The pet will require at least 2 hours in the hospital. This test is also sometimes used to monitor patients with Cushing’s disease, a pet health condition in Brighton, CO.

Imaging: Abdominal ultrasound, MRI or CT scan may be helpful in classifying the type of Cushing’s disease by examining the size and structure of the pituitary gland or the adrenal glands. In the event of an adrenal tumor, ultrasound is also helpful to determine the extent of tumor spread.

How do you treat Cushing’s disease?

Lysodren (also known by its generic name, Mitotane): Lysodren is the most commonly used drug for medical treatment of both pituitary- and adrenal-dependent Cushing’s disease. This drug selectively destroys the cortisol-producing layers of the adrenal gland. Lysodren is convenient to use and relatively inexpensive, but it does have the potential for serious side effects and requires regular monitoring. Lifelong therapy is required.

Some of the side effects of Lysodren use include lethargy, weakness, decreased appetite, vomiting, or diarrhea. Mild side effects can be managed with prednisone, an inexpensive oral medication. In the event of such short-term reactions, Lysodren is discontinued until side effects resolve, and then therapy is resumed, possibly at a lower dose.

More serious problems result when too much of the adrenal cortex is destroyed by Lysodren. Sometimes excess adrenal destruction is permanent and the dog must then be treated for cortisol deficiency, a disorder known as Addison’s disease.

What is Addison’s disease?

Addison’s disease (also called hypoadrenocorticism) is the opposite of Cushing’s disease and results from a deficiency of cortisol. If Lysodren destroys too much of the adrenal gland, Addison’s disease can be a permanent result.

If this occurs, cortisol supplementation becomes necessary to prevent life-threatening shock as the body becomes unable to adapt to any sort of stress. Although a serious side effect, this condition is managed with life-long cortisol supplementation.

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