As a dog parent, witnessing your dog experiencing diarrhea and losing weight can be a cause for concern.
These symptoms can point to a number of underlying health issues, ranging from minor conditions to more serious diseases.
It’s essential to recognize when these symptoms require professional attention and what you can do to help your dog.
We outline why dogs might experience diarrhea and weight loss, possible causes, and what steps you should take to ensure your dog’s health and well-being.
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Why Dog Diarrhea and Losing Weight Happens
Dog diarrhea and losing weight together can indicate a variety of underlying health issues, ranging from gastrointestinal disorders like inflammatory bowel disease (IBD) to infections, parasites, or even chronic diseases such as diabetes or cancer.
When a dog experiences diarrhea, it can lead to nutrient loss and dehydration, impairing their ability to absorb essential nutrients, which can result in weight loss.
Additionally, conditions like food allergies, stress, or kidney and liver disease can also cause these symptoms.
Causes of Dog Diarrhea and Weight Loss
Dog diarrhea and weight loss can occur for various reasons, some of which are relatively harmless, while others may signal a serious underlying health issue.
Common causes include:
1. Gastrointestinal Disorders
One of the most common causes of dog diarrhea and weight loss is a gastrointestinal disorder.
Conditions such as inflammatory bowel disease (IBD), gastritis, or colitis can affect your dog’s digestive system, leading to persistent diarrhea.
These conditions prevent proper absorption of nutrients from food, resulting in weight loss.
In dogs with gastrointestinal disorders, the lining of the intestines becomes inflamed, which hinders the dog’s ability to digest food properly.
As a result, the food moves too quickly through the digestive system, leading to diarrhea.
Simultaneously, the inflammation may impair nutrient absorption, causing your dog to lose weight despite a normal or even increased appetite.
If you notice your dog has diarrhea for more than a day or two and is losing weight, consult your veterinarian for a diagnosis.
Your vet may recommend a special diet or medication to treat the inflammation and help your dog regain weight.
Related: Dog diarrhea and leg pain (Explained)
2. Parasitic Infections
Parasites, including intestinal worms like roundworms, hookworms, and giardia, are common culprits behind dog diarrhea and weight loss.
These parasites rob your dog of essential nutrients, leading to malnutrition and rapid weight loss.
Additionally, parasites can cause your dog to have loose stools or diarrhea due to irritation in the intestines.
If you suspect that your dog has intestinal parasites, a visit to the vet is necessary.
A stool sample will help identify the type of parasite, and your vet can prescribe the appropriate medication to eliminate them.
3. Food Sensitivities or Allergies
Food sensitivities or allergies can also result in diarrhea and weight loss.
When dogs consume foods they are allergic to, their immune systems react negatively, leading to symptoms like diarrhea, vomiting, and weight loss.
Common allergens include beef, chicken, grains, or dairy products.
If you’ve recently changed your dog’s diet or introduced a new food, this could be the cause of the symptoms.
Some dogs may develop food allergies over time, even if they’ve previously tolerated certain foods without any issues.
To determine if your dog has a food allergy, your vet may recommend an elimination diet, where certain ingredients are removed from your dog’s food to see if symptoms improve.
It’s essential to consult your vet before making significant dietary changes to ensure your dog’s nutritional needs are met.
Related: Dog diarrhea and loose stools (Explained)
4. Chronic Infections
Chronic infections, particularly bacterial or viral infections, can lead to a combination of diarrhea and weight loss in dogs.
For example, infections like parvovirus can be severe and lead to persistent diarrhea and malnutrition.
These infections can weaken the immune system, making it difficult for the dog to maintain a healthy weight.
If your dog is showing signs of a viral or bacterial infection, it’s essential to seek veterinary help immediately.
Infections can be life-threatening if not treated properly, so your vet will likely administer antibiotics or antiviral medications, along with fluids to prevent dehydration and support recovery.
5. Cancer or Tumors
While it’s never easy to think about, cancer is a potential cause of both dog diarrhea and weight loss.
Tumors or cancers in the digestive tract, pancreas, or liver can interfere with the body’s ability to absorb nutrients properly, leading to weight loss.
The gastrointestinal upset caused by the tumor can also result in diarrhea.
Some cancers may not be immediately obvious, so if your dog has unexplained weight loss and diarrhea that persists over time, your veterinarian may conduct imaging tests (such as X-rays or ultrasounds) to check for tumors.
If cancer is suspected, early diagnosis and intervention can significantly improve the chances of successful treatment.
Your veterinarian will guide you through treatment options, which may include surgery, chemotherapy, or palliative care to manage symptoms.
6. Diabetes
Canine diabetes is another condition that can cause a dog to lose weight despite eating normally or even more than usual.
When a dog is diabetic, their body is unable to properly process sugar in the bloodstream, leading to weight loss, dehydration, and increased thirst.
Additionally, diabetes can result in gastrointestinal upset, including diarrhea.
If your dog is showing signs of diabetes, such as excessive thirst, urination, or lethargy, it’s essential to visit your veterinarian for blood tests.
Managing diabetes typically requires insulin therapy, dietary changes, and regular monitoring.
7. Stress and Anxiety
Stress is an often-overlooked factor when it comes to dog diarrhea and weight loss.
A dog undergoing significant stress—such as a change in environment, separation anxiety, or a traumatic event—can experience gastrointestinal distress that leads to diarrhea.
Stress can also affect a dog’s appetite, leading to weight loss.
Addressing the source of stress is key. If your dog’s stress is due to environmental changes, such as moving to a new home or the arrival of a new pet, gradual acclimatization and a stable routine can help.
In some cases, your vet may recommend medications to help your dog manage stress.
Related: Dog diarrhea and twitching (Explained)
8. Kidney or Liver Disease
Kidney and liver diseases can lead to diarrhea and weight loss in dogs.
When these organs aren’t functioning properly, they struggle to filter waste and maintain proper hydration and nutrient levels.
As a result, diarrhea may develop, and weight loss can occur due to malnutrition or poor absorption of nutrients.
Kidney or liver disease requires medical attention as soon as possible.
Your veterinarian may conduct blood tests and imaging studies to assess organ function.
Depending on the severity, treatment may involve medication, special diets, and possibly fluid therapy.
What to Do When Your Dog Has Diarrhea and Is Losing Weight
If your dog is experiencing diarrhea and losing weight, it’s crucial to take action right away.
Here are a few steps to consider:
Consult a Veterinarian: The first step is to get a professional diagnosis. A vet will perform an exam, run tests, and provide treatment based on the underlying cause of the symptoms.
Keep Track of Symptoms: Monitor your dog’s behavior, including how long the diarrhea lasts, any changes in appetite, energy levels, and the presence of additional symptoms like vomiting or lethargy.
Provide Hydration: Diarrhea can lead to dehydration, so it’s vital to ensure your dog has access to fresh water at all times. In some cases, your vet may suggest oral rehydration solutions.
Dietary Adjustments: If food allergies or sensitivities are suspected, your vet may recommend a special diet to help your dog regain weight and reduce gastrointestinal distress.
Follow the Treatment Plan: Whether it’s antibiotics for an infection, deworming medication, or a special diet for IBD, following your vet’s instructions is essential to helping your dog recover.
Key Takeaways
When a dog is experiencing diarrhea and losing weight, it’s a sign that something is amiss in their body.
There are many potential causes for these symptoms, including gastrointestinal disorders, infections, food sensitivities, and more serious conditions like cancer or diabetes.
It’s essential to seek veterinary care to determine the cause and begin treatment as soon as possible.
With the right care and attention, most dogs can recover and regain their health.