probiotic dog shampoo for dry and itchy skin

Does Probiotic Dog Shampoo Really Work?

Your dog's skin hosts an intricate and dynamic ecosystem comprising various microorganisms, including bacteria, fungi, viruses, and mites which acts as a protective barrier against pathogens and plays a crucial role in maintaining skin health.

A 2014 study shed light on the complexity of the skin microbiome in dogs, revealing an astonishing 17 different phyla of bacteria and even more diversity amongst the species. It also discovered that different regions of the body contained different microbes.

Notably, this study also found a marked difference between the skin microbiome of healthy dogs and those with allergies, atopic dermatitis, and other skin issues with regard to bacterial diversity.

Healthy dogs have bacteria like Ralstonia, Micrococcus spp., Staphylococcus epidermidis, S. xylosus, Clostridium spp., Propionibacterium acnes, Acinetobacter spp. and more. In contrast, dogs with skin allergies, itchy skin, or atopic dermatitis tend to have a reduced or absent bacterial diversity presence.

This small but insightful study suggests a potential link between skin health and microbial diversity in dogs, especially those suffering from allergies, atopic dermatitis, dry skin, and more.

A 2023 study on Shiba Inu dogs found that in dogs where their skin bacteria was compromised, so too were their gut bacteria. This mirrored human studies with the same finding.

As pet parents have become more knowledgable about the skin microbiome, it has led many to consider probiotic dog shampoos in the hopes of fostering a healthier skin microbiome to potentially alleviate allergies and skin issues.

Beneficial Bacteria Is More Than Skin Deep

So, if an imbalance in the skin microbiome can improve skin health should we just liberally applying probiotics on our dogs' skin? Well, it may be tempting but it likely won't solve the problem and long term it may introduce more issues... read on...

Not all probiotics are beneficial for canine (or human) skin. The incorrect strains or an imbalance in probiotics could disrupt the natural skin microbiome, leading to more issues rather than resolving them. 

Most importantly, if you don't improve the gut microbiome, you won't have long term success with improving the skin.

It is just that simple. 

Further, there are significant issues with topical probiotic products that need to be addressed (we talk about those below).

What Are Probiotics? 

You probably already know that a probiotic is defined as "

live microorganisms that, when administered in adequate amounts, confer a health benefit on the host.”

But, do you know that statement means these 3 things?

  1. The probiotic strains used in the product must have documented experiments in peer review journals that they are beneficial for the intended purpose. 
  2. The product must contain sufficient live microorganisms at the time of use that are equivalent to when the product was shown in studies to be beneficial. 
  3. The delivery method, dosage, and duration of use must be based on scientific evidence.

Many of the probiotic dog shampoos on the market do not meet these criteria and they introduce some ingredients that have compromised the viability of the probiotics.   They also contain ingredients that may have links to skin allergies or even long term toxicity.


The Problem with Probiotic Dog Shampoo

Topical probiotic products, including probiotic dog shampoo face several unresolved issues with the viability of the probiotics: 

  1. Freeze Drying & Premature Rehydration: While freeze drying probiotics is the best method to preserve them prior to use, if the probiotics are exposed to water or other liquid, they may prematurely hydrate which causes them to multiply and die (losing potency).
  2. Preservatives Destroy the Probiotics: Probiotic dog shampoos (and human probiotic cosmetics) are not manufactured under sterile conditions and don't require sterility testing, so manufacturers add antiseptics (preservatives) to control microbial growth in the shampoo. These preservatives very likely affect the viability of probiotic strains and alter the skin's natural microbiota by introducing an antiseptic to the skin. Bottom line: If you see probiotics in a dog shampoo with strong preservatives, it is very likely the preservative has destroyed the probiotic. 
  3. Final Product Testing Of Probiotic Viability: After the product is manufactured, in its final form, it is not tested to determine if the probiotics are still viable. Ideally, the manufacturer would test the probiotics prior to use. Then, test them immediately after manufacturing, months after manufacturing, up to when the product expires to determine the probiotics remain viable in the product through the expiration date. We do know that rehydrating the probiotic will affect viability. Combined with a preservative, it is unlikely probiotics survive.

Many of the companies that are leading the human cosmetics industry for the incorporation of probiotics in products aren't using live cultures of probiotics because they recognize the freeze dried bacteria can't survive the moisture and preservatives.

Instead, they are using the ferments from the live bacteria. They do not make the claim of using probiotics, because they don't.

Their products are created with probiotic ferments (postbiotics) and prebiotics.


Is Probiotic Dog Shampoo Really All Natural?

The effectiveness and viability of probiotics in dog shampoos, especially when mixed with preservatives in a liquid solution, is certainly subject to question.

Additionally, the claim of these products being "all natural" is another aspect that needs careful examination.

Many probiotic dog shampoos are marketed for their natural ingredients, which is a significant selling point for pet parents.

However, it is crucial for pet parents to thoroughly investigate the ingredient lists of these shampoos. This vigilance ensures that they are choosing products that are safe for their pets' long-term skin health.

Upon examining the ingredients in some popular probiotic dog shampoos, we observed a combination of synthetic chemicals that are certainly not all natural nor are they the best ingredients for allergies or itchy skin.

Let's take a look at some of these ingredients to see if they are truly all natural and good for dogs with allergies or itchy skin?

  • Methylchloroisothiazolinone and Methylisothiazolinone: Unfortunately, there are still dog shampoo manufacturers that are using these synthetic preservatives. While they are very effective at preventing bacterial growth, they are also known to cause skin irritations and allergic reactions in both dogs and humans. Canada has placed them on a restricted list for use in human cosmetic products. If methylisothiazolinone (MI) is present in a formulation in combination with methylchloroisothiazolinone (MCI), the cumulative, total concentration of MI and MCI may not exceed 0.0015% due to skin irritation and allergic reactions. Notably, there is also scientific evidence that shows these preservatives may actually KILL the natural bacteria on the skin. If the preservative is strong enough to kill the natural bacteria on the skin, it would very likely kill the probiotics added to the shampoo. Preservatives are not specific about what they kill. If a preservative is a strong anti-bacterial, it will kill all bacteria indiscriminately.
  • Fragrance: The term "fragrance" on a label often hides a multitude of potentially harmful chemicals. Synthetic fragrances can cause skin irritations and respiratory issues in dogs, particularly those with sensitivities or allergies. Additionally, it's challenging to determine the specific ingredients used in the fragrance, making it difficult to assess their safety.
  • Cocamidopropyl Betaine: This surfactant is frequently found in shampoos for its ability to create foam and lather. While it's generally considered safe, some dogs may develop skin reactions, making it important to be mindful of potential sensitivities in your pet. While it is marketed as all natural, it is a mixture of   coconut oil and dimethylaminopropylamine that goes through 4 chemical reactions before it is in its final ingredient. 
  • Stearalkonium Chloride: This ingredient is often used as a conditioner and detangler. While it is not inherently toxic, it can cause skin and eye irritation, and some dogs may be more sensitive to it than others.

 We encourage you to look up all ingredients in pet shampoos and choose a shampoo like 4-Legger that is truly all natural. 

Improving Your Dog's Skin and Coat

If you're concerned about the viability of probiotics in dog shampoo and the potential dangers of certain ingredients in probiotic dog shampoos, you may want to consider doing the following:

  1. Test Your Dog's Poo: There are a number of companies that now offer testing of your dog's feces to see if healthy gut bacteria are present, if harmful bacteria are present, and if your dog's gut microbiome is out of balance. This should be your first stop to establish a healthy baseline of your dog's gut microbiome so you can determine the underlying cause of digestive, skin, or allergy problems. 

  2. Supplement With Oral Prebiotics, Digestive Enzymes, and Probiotics: A 2023 human study demonstrated that ingestion of probiotics was actually more beneficial than topical products as you heal the body from the inside out and you know the probiotics are viable upon ingestion. 

    The gut microbiome plays a HUGE role in allergies and skin health as 70%–80% of immune cells live in the gut. If your dog suffers from allergy symptoms, rebalancing their gut microbiome will help. Find a reputable company that makes prebiotic and probiotics that are specific to dogs (not humans). Given the survivability of probiotics, it is highly recommended you purchase the freeze-dried powder, not the chewables, and apply it to your dog's food just prior to consumption as it will have the highest probability of survivability. Chewable supplements are subject to being exposed to moisture just like shampoo so the viability of the final product may be compromised.
  3. Recolonize the Gut: You can purchase donor fecal probiotics (probiotics taken from the poo of healthy dogs) to recolonize the bacteria in your dog. It sounds kinda gross... but it does work.

  4. Balanced Diet: Providing your dog with a well-balanced diet that is low in carbohydrates can significantly impact their skin and coat health. Learn how to calculate the carbohydrate content of your dog's food

  5. Use A Truly Natural Dog Shampoo: It is essential to be cautious and informed about the ingredients in your dog's shampoo and select products  like 4-Legger Organic Dog Shampoo, with ingredients that do not have links to allergies, itchy skin, and other potentially toxic side effects. Next week we will give you a DIY probiotic dog shampoo recipe without harsh preservatives you won't want to miss! 



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