Owning a pet with a chronic illness can present some unique challenges. A chronic illness can last anywhere from three months to the lifetime of the pet. This article will give a basic overview of the most common types of chronic illnesses and their treatment.

Urinary Tract Infections (UTIs)

Urinary tract infections are common in both cats and dogs. They are caused by a build-up of bacteria in the urethra and bladder. Physical symptoms include blood in the urine, trouble urinating, urine with a very strong smell and incontinence. We often don’t notice what our pet’s urine looks or smells like, so our pets may “tell” us that there are problems by urinating on the bed, in our favorite shoes or right behind us as we are pouring coffee.

The good news is that UTIs are easily cleared up with antibiotics. Some pets will develop several urinary tract infections in their lifetime, making it a chronic condition. It is one of the easiest chronic illnesses to deal with. UTIs are most common in female pets and unneutered males.


Diabetes is a condition in which glucose (sugar) levels in the blood become too high. It is very common in cats and dogs. Symptoms may include increased drinking and urination, increased appetite followed by unexplained weight loss, vomiting, lethargy and weakness in rear legs.
Most pets with diabetes do well on daily medication or insulin injections and a low-carbohydrate diet.

Renal failure

Renal failure usual occurs in cats. The kidneys are not able to process waste products effectively. Symptoms include increased thirst and urination, nausea or gagging, vomiting, drooling, dehydration, constipation, weight loss, breath that smells like ammonia, and lethargy.
Renal failure is usually treated with subcutaneous fluids given at home and a low-phosphorous diet.

Irritable Bowel Disease (IBD)

Most often seen in cats, IBD is caused by intolerance to something in the diet. The symptoms include diarrhea, vomiting and weight loss.

IBD is treated with antidiarrheal drugs and antibiotics. The pet’s diet should also be changed. Avoid foods that contain grains, food coloring and dye, wheat gluten, soy, beef and fish.

Skin diseases

Skin problems occur more often in dogs than cats. Fleas and food allergies are the most common causes of skin problems. Symptoms include scratching and/or biting a particular area on themselves, hair loss and hot spots.

If the skin problems are due to an allergy to fleas, give the pet a bath using a mild shampoo to calm the skin and apply a flea preventative (if using a topical solutions, wait 24-48 hours after giving your pet a bath). In the case of food allergies, it is vital to determine the specific allergy and then eliminate that ingredient or ingredients from the diet. This can take many months of food trials. Sometimes allergy symptoms can be treated with antihistamines or steroids. Food allergies are one of the most difficult chronic problems to deal with, but once you determine what those allergies are, you can alleviate the symptoms.


Hypothyroidism means “low thyroid” and occurs when the thyroid gland is unable to secrete enough thyroid hormone, causing a decrease in metabolism. It occurs most commonly in dogs. The symptoms are lethargy, weight gain, dry skin, hair loss, intolerance to cold, chronic ear infections, change in behavior (unprovoked aggression, anxiety), and seizures.

It is treated easily with a daily oral dose of synthetic thyroid hormone. Blood work will need to be done every 6 to 12 months to make sure the medication is being effective. Depending on the results of the blood work, the dosage may need to be adjusted.


Hyperthyroidism or, “high thyroid” occurs mostly in cats and is an enlargement of the thyroid and production of too much thyroid hormone. Symptoms include weight loss, increased appetite, vomiting, increased thirst and urination, hyperactivity and diarrhea.

Hyperthyroidism is treated with anti-thyroid medications. Blood work should be done every 6 to 12 months and the dosage adjusted as needed.

The hardest part of having a pet with a chronic illness is having it diagnosed. As you can see, many of the illnesses have similar symptoms. Blood work usually needs to be done to make a definite diagnosis. Other diagnostic tests may need to be performed in some cases. The good news is that most chronic diseases are easily treated and your pet can live a long and happy life in spite of having a chronic medical condition. For a comprehensive list of common pet diseases including chronic, visit http://www.petdoc.ws/Pet_Health_Information.htm.