Can Probiotics Cause Diarrhea in Dogs? What are the Side Effects?

Probiotics are live microorganisms, typically bacteria or yeasts, beneficial to a dog’s digestive system. These "good" bacteria are naturally found in their body, particularly in their gut, and are present in certain foods and supplements. 

Probiotics cause diarrhea in dogs when first introduced or if the dosage is too high. Probiotics are beneficial for digestive health, but pet owners asking, “Can probiotics cause diarrhea in dogs?” must know that the answer is yes. Introducing probiotics disrupts the balance of bacteria in the gut, leading to gastrointestinal upset in some dogs. 

Diarrhea is one of the side effects of probiotics in dogs, with additional gastrointestinal symptoms such as bloating, gas, and stomach discomfort. The occurrence of diarrhea as a side effect of probiotics in dogs depends on the individual dog's sensitivity, the specific strains of probiotics used, and the dosage administered. Some dogs experience diarrhea as their digestive system adjusts to the introduction of new bacteria, while others develop diarrhea if fed probiotics excessively.

Introduce probiotics gradually and monitor for any signs of digestive upset, including diarrhea. Probiotics are one of the supplements that cause diarrhea in dogs. Consult with a veterinarian before starting probiotics to minimize the risk of adverse effects or interactions if a dog has a history of gastrointestinal issues or is on medication. Discontinue the supplementation if diarrhea persists or worsens after starting probiotics.

Can Probiotics Cause Diarrhea in Dogs?

Yes, probiotics can cause diarrhea in dogs. Introducing probiotics to a dog's diet helps restore the balance of good bacteria in the intestines, promoting better digestion and nutrient absorption. Most dogs tolerate probiotics well, but some experience temporary gastrointestinal issues such as diarrhea as their system adjusts to the new bacteria.

“There is a possibility of constipation or loose stools in some animals after taking probiotics or prebiotics, which can be resolved by adjusting the dose. At first, some animals may experience flatulence and/or looser stools, especially when given high-dose multistrain probiotics. In such cases, reducing the dose for the first few days is often enough to alleviate these symptoms, after which the dose can be increased back to full,” according to the report by Suchodolski, J. titled “Probiotics, Prebiotics, Synbiotics, and Intestinal Health of Dogs and Cats,” 2020.

Monitoring a dog's response and consulting with a veterinarian help address any concerns or determine the appropriate probiotic strain for a dog's specific needs.

What are the Side Effects of Probiotics for Dogs?

The side effects of probiotics for dogs are listed below. 

• Gastrointestinal Upset: Stomach upset includes symptoms like diarrhea, bloating, gas, and discomfort. Dogs usually experience symptoms when they first start probiotics or are given a too-high dosage.
• Allergic Reactions: Some dogs are allergic to certain strains of bacteria found in probiotics or other supplement ingredients. Signs of an allergic reaction include itching, hives, swelling, or difficulty breathing.
• Changes in Bowel Habits: Probiotics are used to regulate bowel movements. The beneficial bacteria sometimes cause changes in stool consistency or frequency, such as constipation or diarrhea.
• Overgrowth of Harmful Bacteria: Probiotics lead to an overgrowth of harmful bacteria in the gut in rare cases, leading to infections or other health issues.
• Immune System Stimulation: Probiotics influence the balance of bacteria in the gut, which stimulates the immune system. The immune stimulation periodically leads to autoimmune reactions or exacerbates existing autoimmune conditions.
• Interaction with Medications: Probiotics interact with certain medications by enhancing their effects or inhibiting absorption. Consult with a veterinarian before giving probiotics to a dog taking other medications.
• Potential for Contamination: Supplements such as probiotics risk contamination by harmful bacteria, toxins, or other substances. Choose a reputable brand and properly store probiotics to minimize contamination risk.

When should you give Probiotics to Dogs?

You should give probiotics to dogs with their meals to aid digestion and promote balanced gut flora. Probiotics benefit dogs with digestive issues when administered between meals or on an empty stomach to allow for better absorption. 

Consult a veterinarian before introducing probiotics to the dog’s diet. Certain health conditions, such as antibiotic therapy or gastrointestinal disorders, require specific timing recommendations from a veterinary professional to ensure the probiotics are most effective. 

“Probiotics need 1 to 3 days to colonize the intestines. When the goal is prevention of stress-related diarrhea (during periods of weaning, boarding, or traveling or for working dogs), prophylactic administration of a probiotic a few days to weeks ahead of the event may increase success. Similarly, if the goal is prevention of antibiotic-associated GI signs, administering probiotics a few days ahead of a procedure will increase success,” according to the report by Suchodolski, J. titled “Probiotics, Prebiotics, Synbiotics, and Intestinal Health of Dogs and Cats,” 2020. 

Understanding what is probiotics in dogs determines their suitability for the dog’s diet before introducing them. Probiotics are not suitable for every situation or dog. Determining the optimal timing for administering probiotics to dogs is crucial for maximizing their effectiveness. Veterinarians guide when to give probiotics based on the dog's specific health needs and conditions.

What is the Connection Between Probiotics and Diarrhea in Dogs?

The connection between probiotics and diarrhea in dogs involves the delicate balance of bacteria in the dog's digestive system. Introducing new probiotic strains disrupts the balance, leading to digestive issues like diarrhea.

Probiotics, often called 'good' bacteria, play a crucial role in maintaining intestinal health in dogs. The beneficial bacteria help digest food, absorb nutrients, and maintain a healthy gut environment.

An overgrowth of harmful bacteria or a deficiency of beneficial ones results in gastrointestinal problems such as diarrhea. Factors such as stress, infections, or dietary changes trigger imbalances in the gut microbiome, which unsettle the equilibrium of the dog’s digestive system.

How Can Probiotics Impact a Dog's Digestive System?

Probiotics can impact a dog's digestive system by promoting the growth of beneficial bacteria, improving nutrient absorption, and supporting health. Probiotics enhance the dog's immune system, leading to better health outcomes. “Probiotic supplementation has a small but significant effect on the gut microbiome in healthy dogs, with increased abundance of beneficial bacteria and decreased E. coli abundance,” according to the study by Tanprasertsuk, J., Shmalberg, J., Jha, A., Perry, L., & Honaker, R. titled “The Effect of Probiotics Supplementation on the Gut Microbiome of Healthy Dogs Assessed Using Metagenomic Sequencing: A Randomized Control Trial,” 2020.

Good bacteria in probiotics aid in breaking down food components, allowing for better nutrient absorption. Enhanced absorption contributes to improved energy levels and dog well-being. Maintaining a healthy balance of gut bacteria and probiotics regulates the dog’s digestive system and prevents digestive issues such as diarrhea and constipation. The strengthened immune system from probiotic use enables the dog to fend off infections and diseases better, leading to fewer vet visits and improved quality of life.

What are the Benefits of Probiotics in Dogs?

The benefits of probiotics in dogs are listed below.

• Improved Digestive Health: Probiotics help maintain a healthy balance of bacteria in the gut, facilitating proper digestion and nutrient absorption. The supplements help alleviate symptoms of gastrointestinal disorders such as diarrhea, constipation, and irritable bowel syndrome (IBS).
• Support for Immune Function: A significant portion of the immune system resides in the gut, and a balanced gut microbiome is essential for optimal immune function. Probiotics help strengthen the immune system and protect against infections by promoting the growth of beneficial bacteria and crowding out harmful pathogens.
• Reduced Risk of Food Allergies: Probiotics reduce the risk of food allergies and intolerances by supporting the integrity of the gut barrier and modulating the immune response to allergens.
• Management of Inflammatory Conditions: Probiotics contain anti-inflammatory properties and reduce inflammation in the gut and throughout the body, managing conditions such as inflammatory bowel disease (IBD) and arthritis.
• Prevention of Antibiotic-Associated Diarrhea: Antibiotics disrupt the natural balance of bacteria in the gut, leading to diarrhea and other gastrointestinal issues. One of the benefits of probiotics in dogs is restoring balance and reducing the risk of antibiotic-associated diarrhea in dogs undergoing antibiotic treatment.
• Support for Skin Health: The gut microbiome’s state influences skin health, and probiotics help improve conditions such as atopic dermatitis and allergic skin reactions by modulating the immune response and reducing inflammation.
• Management of Stress-Related GI Issues: Dogs experience gastrointestinal (GI) issues due to stress, anxiety, or environmental changes. Probiotics help mitigate these issues by promoting a healthy gut microbiome and supporting the gut-brain axis.
• Maintenance of Oral Health: Some probiotic strains have been shown to inhibit the growth of harmful bacteria in the mouth, which helps prevent dental issues such as plaque buildup, gum disease, and bad breath.

What are the Limitations of Probiotics in Dogs?

The limitations of probiotics in dogs are listed below.

• Limited Research: The scientific evidence supporting probiotic efficacy and safety in dogs still needs to be developed despite growing interest in their application. More research is required to fully understand the optimal strains, dosages, and applications of probiotics for various health conditions in dogs.
• Strain-Specific Effects: Not all probiotic strains are created equal, and different strains affect dogs' health differently. The efficacy of probiotics depends on factors such as strain specificity, viability, and dose. Choosing the right probiotic strain for a specific health condition necessitates clear guidance from research.
• Individual Variability: Dogs contain unique microbiomes like humans. A dog’s response to probiotics varies based on age, breed, diet, health status, and genetics. Probiotic benefits for one dog do not guarantee success for another dog. Trial and error is expected to find an individual dog's most effective probiotic regimen.
• Transient Effects: Probiotics are living microorganisms that need to colonize the gut to exert their beneficial effects. Many probiotic strains are transient and do not persist in the gut for an extended period. The benefits diminish over time once probiotic supplementation discontinues.
• Inconsistent Quality Control: The quality and potency of probiotic supplements vary widely among brands and products. Some probiotics lack the stated number of viable bacteria or are contaminated with harmful substances. Choose reputable brands with good manufacturing practices to ensure the safety and efficacy of supplements for dogs.
• Interactions with Medications: Probiotics interact with certain medications, such as antibiotics, immunosuppressants, and antifungal drugs. The interactions affect medication absorption, efficacy, or metabolism, sometimes leading to unintended consequences. Consult a veterinarian before combining probiotics with other medications.
• Potential for Adverse Effects: Probiotics are considered safe for most dogs but occasionally cause adverse effects such as gastrointestinal upset, allergic reactions, or overgrowth of harmful bacteria. Monitor for signs of adverse reactions and adjust the probiotic regimen to ensure supplementation safety.

How Much Probiotics can I give my Dog?

How much probiotics you can give your dog averages between one to ten million colony-forming units (CFU) per day, depending on the probiotic strain. Factors such as size, breed, and health status determine the appropriate dosage.

Large dog breeds such as Great Danes or Mastiffs benefit from a higher dosage of probiotics than toy breeds like Chihuahuas. Larger breeds have more body mass and require more probiotics to maintain optimal gut health.

Consider any specific health conditions of dogs. Dogs with digestive issues or sensitive stomachs need a specialized probiotic formulation tailored to their needs. 

Can I give my Dog Probiotics every day?

Yes, dogs can be given probiotics every day. “A daily dose of 20 billion CFU of probiotics (L. reuteri, P. acidilactici, E. faecium, L. acidophilus, B. animalis, L. fermentum, L. rhamnosus) can improve gut health in healthy dogs,” according to Tanprasertsuk, J., Shmalberg, J., Jha, A., Perry, L., & Honaker, R. titled “The Effect of Probiotics Supplementation on the Gut Microbiome of Healthy Dogs Assessed Using Metagenomic Sequencing: A Randomized Control Trial,” 2020.

Daily probiotic supplementation is safe for dogs if guidelines and dosages are followed. Regularly using probiotics, such as Enterococcus faecium, helps maintain a healthy balance of gut bacteria over time.

What are the Best Probiotics for Dogs?

The best probiotics for dogs are listed below.

• Honest Paws Well Pre + Probiotics: The supplement contains a blend of prebiotics and probiotics designed to support digestive health in dogs. Prebiotics serve as food for probiotic bacteria, helping them thrive in the gut. Honest Paws uses high-quality, natural ingredients in its products, formulated to promote a healthy balance of gut bacteria and support well-being.
• Purina Pro Plan Fortiflora Probiotic Supplement: Fortiflora is a recognized probiotic supplement veterinarians recommend for dogs with digestive issues. The product contains a specific strain of probiotic bacteria called Enterococcus faecium SF68, which has been shown to promote digestive health and immune function in dogs. 
• Native Pet Vet-Created Probiotic Powder for Dogs Digestive Issues: The probiotic powder is formulated by veterinarians and contains a blend of beneficial bacteria to support digestive health in dogs. The powder addresses diarrhea, gas, bloating, and other digestive discomforts. Native Pet emphasizes using high-quality, human-grade ingredients in their products, and the probiotic powder easily mixes into a dog's food for convenient administration.

Consider factors such as health concerns, the quality and potency of the product, a dog's individual needs and preferences, and recommendations from a veterinarian when choosing the best probiotics for dogs. Monitor the dog's response to probiotics and adjust as needed to ensure optimal digestive health and overall well-being.

Do Probiotics Help Dogs with Itchy Skin?

Yes, probiotics help dogs with itchy skin. “Probiotic enema with Lactobacillus plantarum and Lactobacillus paracasei significantly reduced itching in dogs with atopic dermatitis,” according to the study by Ural, K., Erdoğan, S., Balikçi, C., Erdoğan, H., & Içaçan, Ş. Titled “Inovatif Gastroentero-Dermatoloji Kapsamında Muhtelif Yöntem Geliştirme I: Lactobacillus plantarum ve Lactobacillus paracasei ile Probiyotik Eneması Atopik Dermatitli Köpeklerde Anti-Pruritik Etkinlik Sağlar Mı?,” 2021. 

Alleviating skin issues using dog probiotics for itchy skin supports the immune system and addresses underlying allergies. “Early exposure to probiotics, like Lactobacillus rhamnosus GG, significantly decreases allergen-specific IgE and partially prevents atopic dermatitis in dogs in the first 6 months of life,” according to the study by Marsella, R., Santoro, D., & Ahrens, K. titled “Early exposure to probiotics in a canine model of atopic dermatitis has long-term clinical and immunological effects,” 2012. Incorporating probiotics with beneficial bacteria strains improves skin health and overall dog comfort.