Why Does My Dog or Cat Have Diarrhea?

Why Does My Dog or Cat Have Diarrhea?Furbabies can't tell their pet parents when they're not feeling well. Unfortunately, diarrhea is one noticeable sign that a four-legged companion may be ill. How can you tell if your pet has a temporary tummy issue or something more serious?

Here are some of the common causes of diarrhea in pets, and the illnesses that are typically associated with this health condition.

What is Diarrhea?

Diarrhea is a common health condition where the intestines produce unformed, watery stools. The condition is not an illness, but a symptom of other underlying medical issues. Pets with diarrhea can have three or more bowel movements per day.

The gastrointestinal condition is so widespread, it is the most claimed condition at PetPlan Insurance according to its vice president of veterinary services, Dr. Jules Benson.

"It could be brought on by anything from a virus or parasites to poisoning, allergic reaction, autoimmune disease, or even certain types of cancer,"  Dr. Benson said in a PetMD interview. The condition usually occurs when pets ingest something that doesn't agree with them.

Most pet parents shouldn't worry if their fur baby suffers from a brief bout of diarrhea. Depending on its cause, most mild cases resolve without treatment within 48 hours, depending on their cause. Diarrhea that lasts for more than three days (or includes other clinical symptoms) is a sign of more serious health conditions.

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When Should You Take Your Pet into the Vet?

Owners should closely watch dogs and cats that have diarrhea. Does your pet have additional health symptoms like a rising temperature or lethargy? Pets that have additional symptoms could have a serious medical condition that requires immediate treatment.

Bring your pet to our office if they display any of the following 14 symptoms:

  • Bathroom accidents (in the house or outside of a litter box)
  • Watery, loose, stools (diarrhea)
  • Loss of appetite (anorexia)
  • Weight loss
  • Mucus in stool
  • Vomiting
  • Fever
  • Abdominal pain or sensitivity
  • Dehydration
  • Black, tarry stools or bloody diarrhea
  • Lethargy
  • Weakness
  • Straining to go to the bathroom
  • Pale gums

Take your fur baby to the vet if their health worsens or their illness progresses. Early intervention and treatment can improve your pet's chances of recovering.

How Veterinarians Diagnose Underlying Health Conditions that Cause Diarrhea

Veterinarians use diagnostic tests to identify underlying health conditions that may cause diarrhea. Additionally, these test help veterinarians rule out other causes of disease within pets. There are four common screenings that veterinarians use.

  • CBC (Complete Blood Count) - This test can identify the levels of glucose, proteins, electrolytes, cholesterol, endocrine levels, and digestive enzymes within your pet's body. It can also pinpoint hormonal or endocrine-related issues. Depending on what's going on, your vet might also run a chemistry panel along with the CBC.
  • Endoscopy exam  - This screening allows a veterinarian to see the internal parts of your pet's organs. A small scope with a camera will film your pet's gastrointestinal tract, so your veterinarian can check for tumors or foreign objects.
  • Radiograph - This x-ray examination can penetrate your pet's tissues and help our experts identify any abnormalities in your pet's GI tract.
  • Stool and rectal swab samples - Our veterinarians may perform one of three fecal screenings: the smear, flotation, or centrifugation test. Fecals help our experts check for parasitic infections in your pet like Giardia.

Cats may receive a Feline Leukemia-Feline Immunodeficiency Virus test to find out if your pet could be infected. 

Nine Common Causes of Diarrhea in Dogs and Cats

Pets can develop diarrhea for a variety of reasons. Here are nine common issues that cause diarrhea.

1. Recent Dietary Changes

Sometimes, owners change their pets' regular food when they become finicky eaters. Swift dietary changes can cause diarrhea in pets. Dogs need several days to adjust to dietary changes. They may suffer from diarrhea after owners switch their diets from dry kibble to natural, raw foods. 

Pet owners should introduce new foods in small portions to help their GI tracts adjust to the new nutrients.

2. Food Intolerances and Allergies

Dogs and cats can suffer from food sensitivities and allergies, just like people do. When pets have chronic, long-term diarrhea, it may be a sign your pet has a food intolerance or allergy. Common dietary triggers include diets rich in fat, gluten, and dairy.

READ MORE: Does My Pet Have Allergies?

Felines are obligate carnivores: their bodies require meat to survive. Cats can develop allergies when owners feed them the same food for too long. This issue can inflammation in their GI tract. Additionally, cats cannot drink cow's milk, since they lack the enzymes that can break down lactose. Cats can vomit and suffer from diarrhea after drinking milk.

Certain breeds of dogs are sensitive to foods like wheat and dairy. Veterinarians recommend that dogs follow a food elimination diet to isolate the allergen in their diet. Owners should re-introduce foods slowly into the diet, then check to see which ones cause a reaction.

3. Eating Spoiled Food

Cats and dogs love snacking anything that looks like a delicious treat. These meals can include foods inside trash cans or dumpsters. When pets eat spoiled produce, they may catch nasty bugs that upset their stomachs. These diarrhea cases usually clear up within a day. Owners must keep all rotten foods out of reach to prevent their furry friends from eating it.

4. Parasites

Has your energetic, bright-eyed pet slowed down after a bout of diarrhea? They could have an intestinal parasite. Pets can become infected after drinking polluted groundwater or contaminated food. Additional symptoms may involve vomiting, anemia, and lethargy.

Most parasitic infections are brief, but untreated infections can cause life-threatening conditions. Infected animals can pass parasites to uninfected pets and human beings.

READ MORE: How to Prevent and Treat 5 Common Parasites in Dogs and Cats

Pets with weakened immune systems are more likely to contract parasitic infections. Seek veterinary care if you suspect your pet has a parasitic infection.

5. Viral and Bacterial Infections

Your pet's diarrhea can be a sign of bacterial or viral infections. Viral infections such as the coronavirus, distemper, or parvovirus can cause acute diarrhea. Salmonella can also trigger illness. Dogs may have these illnesses if they are lethargic, vomiting, or have muscle weakness.

Cats can develop diarrhea, dehydration, and extreme weight loss after a bacterial infection. Usually, these infections occur when too much bacteria accumulates in their small intestines. Most bacterial infections in cats clear on their own. Some, however, require treatment with medications. 

6. Stress and Anxiety

Like their human counterparts, pets can develop digestive issues from stress. If other underlying health conditions are ruled out by a veterinarian, they diagnose your pet with idiopathic diarrhea (which has no physical cause).

The following situations can be stressful for pets. They include:

Providing your pet with extra exercise, activities, and attention can help release stress and reduce their gastrointestinal episodes. Owners should also supplement their cats and dogs diets with probiotic to reduce any idiopathic issues. 

7. Toxic Substances, Plants and Poisons

Pets can become curious about the smells and tastes of household products and plants. Like children, they can ingest these substances without knowing they're dangerous. These toxins can cause diarrhea or other illnesses.

Do not feed dogs chocolate or mushrooms. These foods are poisonous to them. Other hazards include medications, laundry detergents, pesticides, herbicides, charcoal, and household cleaners, and plants. For a complete listing of poisons, visit the Pet Poison Helpline's site.

Stop by South Boston Animal Hospital if you believe your pet has eaten a toxic substance. After hours, contact the ASPCA Poison Control Hotline at 1-888-426-4435. Their experts can provide advice that can help save your pets life. 

8. Chronic Diseases

One of the earliest symptoms of chronic diseases is diarrhea. Here are a few medical conditions that pets could have:

  • Kidneys or Liver Cancer - Diarrhea can be a sign that a pet can have a kidney or liver cancer. Testing can identify the issue are an earlier treatable stage.
  • Hyperthyroidism - This condition occurs when the thyroid is overactive. Diarrhea is one of the main symptoms of this illness. If left untreated, your pet can suffer from heart issues.
  • Addison's Disease - This disease occurs in cats and dogs that have an adrenal gland hormonal deficiency.
  • Inflammatory Bowel Diseases - Intestinal tract inflammation can trigger chronic diarrhea. For example, colitis can cause pets to strain when they defecate. Their stools may have mucus or fresh blood.
  • Intestinal Tract Tumors - Diarrhea and vomiting are signs of gastrointestinal lymphoma in both dogs and cats.

9. Indigestible Foreign Objects

Sometimes, pets can swallow foreign objects, like toys. These items obstruct their digestive tracts, causing symptoms like diarrhea, vomiting, and anorexia (lack of appetite). Bring your pet to South Boston Animal Hospital if you suspect your pet has swallowed an item.

Diarrhea Treatments for Cats

A South Boston Animal Hospital veterinarian will use several screenings to identify the cause of your cat's diarrhea. Pet owners can use these methods to reduce digestive distress.

  • Switch Foods - Pet parents should continue feeding cats with diarrhea, unless specifically advised by a veterinarian not to. Your vet may recommend that you switch foods to ensure your pet hasn't developed an allergy to the protein in their regular food. It's also possible you may need to switch back to previous foods if you recently changed your cat's diet, but always check with your vet first.
  • Increase Fiber - Some cats develop diarrhea due to low fiber intake. Try adding natural fiber sources like canned pumpkin.
  • Provide Hydration - Make sure your cat receives water and electrolytes to prevent dehydration. 

Diarrhea Treatments for Dogs

Does your dog have diarrhea? The following treatments can reduce stomach-related symptoms.

  • Diarrhea Medicine for Canines - Owners can use several over-the-counter products that reduce stomach cramping and abdominal pain.
  • Give Soothing Foods - Pets with diarrhea should receive foods that are easy to digest. These include canned pumpkin, boiled chicken, white rice, and bone broth.

Stop by South Boston Animal Hospital if your pet is suffering from chronic diarrhea or other digestive issues. Contact us to schedule an appointment with our veterinary staff today.

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