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Why Does My Dog Have Diarrhea? Most Common Causes

Why Does My Dog Have Diarrhea? Most Common Causes

Diarrhea is one of the most common health issues experienced by dogs; as a pet owner, it is normal to get worried. This should not bother you; the diarrhea is often caused by the dog eating something that does not agree with its body. However, it could also be caused by underlying health issues, and you need to know about them.

The common causes of diarrhea in dogs are a change in your dog’s diet, eating spoiled food, and ingesting foreign objects. Also, bacterial infections, parasitic infections, medications, ingesting toxins or poisons, and inflammatory bowel disease are linked to diarrhea in dogs.

Emotional aspects such as stress or anxiety can trigger intestinal problems in dogs, as much as they do in humans too.

As a dog owner, you should know that the color and consistency of diarrhea speak a lot about your dog’s health, so while you are not worried, you should take quick action.

Dog doing number

What Is The Most Common Cause Of Diarrhea In Dogs?

It is common for most dogs to experience diarrhea in their lifetime for various reasons; puppies and adult dogs experience it alike. To stop diarrhea in your dog, you must understand the cause. We will look at the most common causes of diarrhea in dogs.

Eating Garbage Or Spoiled Food

This is one of the most common causes of diarrhea in dogs; they will scavenge and forage around looking for what they can play with or eat. Moreover, in doing this, they will find spoiled food, they are likely to eat it. Spoiled food is not good for dogs, especially puppies with a weak immune system.

After consuming these, they may start vomiting or experiencing diarrhea. Depending on what the dog consumes, it can develop pancreatitis, a more severe health issue that must be treated properly in severe cases.

A Change In Diet

When you suddenly change your dog’s diet, there is a high chance of it having diarrhea; the new diet can upset the dog’s intestinal tract and stomach. The best thing is to change the dog’s diet gradually; you should slowly decrease the current food while increasing the new food. Implementing a swift change can affect the dog because its body is not used to it, requiring time to adapt.

Bacterial Infections

A dog can also develop diarrhea due to bacteria in improperly cooked or raw meats, decaying vegetables, and meat left outside for a long time. Bacterial gut infections like campylobacter and salmonella can cause severe, bloody diarrhea in dogs. Research has proved that dogs can also get a bacterial infection if it stays close to a dog with it.

Viral Infections

Viral infections like coronavirus, distemper, parvovirus, as well as other rotaviruses, have also been discovered to cause diarrhea in dogs, especially puppies. This has been found to be very deadly, contagious, and even life-threatening. The common signs of diarrhea caused by viral infections are lack of appetite, vomiting, lethargy, fever, and coughing. It would be best to take a dog to the veterinary doctor immediately.

More to learn: Dog Vomiting: Why Does My Dog Keep Throwing Up?

Ingesting Foreign Objects

Dogs are curious animals; this trait has led them to swallow strange objects. Most times, they find these objects interesting, and when consumed, the foreign object is lodged in the lower intestines or the dog’s stomach, resulting in diarrhea. This can be life-threatening and should be treated immediately by the vet.

Signs to watch out for if you think your dog has diarrhea due to ingesting foreign objects are; abdominal pain, vomiting, lack of appetite, lethargy, constipation, and aggression.

Parasitic Infections

Parasitic infections are common in water sources, including stagnant water, ponds, and puddles; they can also be found in animal poop. If a dog eats poop or drinks contaminated water, it is highly likely to have ingested parasitic cysts that cause parasites to develop and stay in the intestine.

This results in diarrhea that looks greasy, frosty, has a strong odor, and a great deal of mucus. Take the dog to a vet if you notice any of these.

dog sick

Allergic Reactions

One of the signs a dog is experiencing allergic reactions is diarrhea; it is a way the body tries to flush out the allergens. Other signs that allergic reactions cause diarrhea the dog is experiencing are sneezing, runny eyes, paw chewing, paw licking, increased scratching around the tail base, as well as scabbed or moist red, itchy skin.

Different things can trigger an allergic reaction in a dog, so it is important to take the dog to the veterinary doctor immediately, so the trigger of the reaction can be identified and you can prevent it from occurring in the future.


Some medications have adverse effects on dogs, some can cause diarrhea as a side effect, and you must know these medications. Medications containing non-steroidal anti-inflammatories (NSAIDs), like Metacam, Rimadyl, and Meloxicam for pain relief and NMDA receptor blockers, can cause diarrhea in dogs.

It has been discovered that the binding substance (adhesive additive), such as lactose added to the medication, is the major cause of diarrhea in dogs. So, before you give your dog any medications, ensure it is confirmed and affirmed by the veterinary doctor.

Additional reading: Why Does My Dog Smell Like Fish? What Can I Do?

What Do I Do If My Dog Has Diarrhea?

Diarrhea is often accompanied by other symptoms like loss of appetite, severe vomiting, and lethargy, amongst others. In treating a dog with diarrhea, you should never give the dog human medication; they have been proven to be toxic to dogs. You should only give your dog medications prescribed by the vet.

You should never withhold food from a dog experiencing diarrhea; the dog has already lost its appetite, so withholding food is worsening the case. It would help if you fed the dog high-fiber, low-fat, easily digestible meals. You should also ensure the dog is not dehydrated, so you need to give it a lot of water to drink.

There are commercial diets available that you can give your dog; however, a bland diet consisting of brown rice and white fish or chicken is great. Potatoes or wholemeal pasta are also a great choice, so are polenta, tapioca, or porridge oats cooked in water. These meals make the dog’s stomach feel better.

It would help if you did not feed a dog with diarrhea fat-filled or dairy meals. Other foods that can help your dog are probiotics, natural yogurt, cottage cheese, peeled boiled potatoes, and egg without oil. You should know that you may not fully treat a dog with diarrhea, and you might have to take the dog to a vet for more intensive treatment and care.

Further Reading: Is It Normal For My Dog To Drink A Lot Of Water? 

When Should I Be Concerned About My Dog’s Diarrhea?

There are some circumstances whereby you have to be worried and concerned, mainly because they are life-threatening. In the event of any of the following circumstances, you need to take the dog to see a veterinary doctor as soon as possible.

  • If your dog has repeated episodes of diarrhea frequently over some hours.
  • If the dog is not responding as normal or is displaying extreme lethargy.
  • If the dog has ingested toxins and is displaying symptoms.
  • If there is excessive blood in the dog’s poop.
  • If the poop has a tarry appearance or is black.
  • If the dog has ingested a foreign object.
  • If the dogs’ gums are white, pale, gray, or bluish.
  • If diarrhea occurs for more than 24 hours.
  • If the dog’s abdomen appears distended or painful.
  • If there are worms in the dog poop.

Final Thoughts

It is normal for a dog to have diarrhea; this should not cause worry, except in severe cases. You need to act fast and take the dog to a vet for analysis and treatment. If you hope to own a pet, especially a dog, you need to be cautious and observant so you can stop the dog from doing dangerous things.

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