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Using Liquid Castile Soap as Pet Shampoo

pet shampoo from castile soap-minYou are likely already aware of the wonders of using castile soap as body wash, but did you know that it is about to become your favorite pet shampoo, too?

Our castile soap is made from a base of organic oils, which means that it is naturally less drying and more moisturizing than most commercially available synthetic soaps. These properties mean that castile soap is just as great a choice for your furry family members as it is for the humans in the house!

Your pets have skin too.

When most of us prepare to bathe our pets, we are focused on the parts of their bodies where we can see or smell visible dirt – usually meaning their fur (or hair, feathers, wool, scales, shell, etc.). However, underneath these protective outer layers, most of our animals have an epidermis that is, more often than not, sensitive to harsh chemicals and susceptible to dryness and irritation. Many of our four-legged friends have allergies as well. For these reasons, it is very important to only bathe them with the gentlest, safest products we can find.

As we know, even though animals can communicate in many ways, they cannot exactly tell us in our words if they are experiencing discomfort. That is why it is our responsibility as their caretakers to be as cautious and informed as possible. DIY pet shampoo made from castile soap is veterinarian recommended as 100% safe for use on your pets. Just make sure to store it in a safe place as ingestion of the soap can cause gastrointestinal upset.

How to Use Liquid Castile Soap as Pet Shampoo

Preparation: Gather Your Materials

  • Choose your container. We recommend picking a container with a lid that seals tightly because you will need to shake your shampoo mixture to combine the ingredients. We like to repurpose old bottles and jars, but you can use any container you like. This recipe makes around five cups (or 40 ounces) of pet shampoo, but you can also scale it up or down as needed.
  • 4 cups of water (adjust as needed)
  • 1/2 cup of liquid castile soap (unscented is best)
Optional Materials
  • 1/8-1/4 cup of either distilled white vinegar or apple cider vinegar will help the soap to rinse clean and will help combat mineral build-up from hard water (use sparingly as vinegar is an acid and will unsaponify the soap, which is why it helps rinse it clean, but you have to use less vinegar than you do water).
  • 1 tablespoon of vegetable glycerin or olive oil will provide more moisture. Vegetable glycerin can be found in the baking or craft sections of most grocery stores and online retailers.
  • 3 tablespoons of baking soda can help give a deeper scrub for pets that are extra dirty or stinky
  • A minimal amount of pet-safe essential oils for scent. Pets can be very, very sensitive to essential oils so always err on the side of caution. Please see our important notes* if you choose to add essential oils to your pet shampoo, and never use essential oils on or around birds or cats.

Step 1: Fill your container with 4 cups of fresh water.

Note: The water makes up almost 90% of your final shampoo’s total volume with this recipe, but you can adjust this amount as necessary based upon the size of your pet and the density of their fur. If your pet has an exceptionally thick coat, it may be suitable to skip this step and use undiluted castile soap instead, as long as the soap you use does not contain over 2% essential oils by volume. Also make sure not to use too much undiluted castile soap, as the concentrated nature of the soap can make it more difficult to rinse, especially on thick hair or fur.

Optional Additions (add these to your water now)
  • Add 1/8-1/4 cup of vinegar to help soap rinse more easily, and to combat mineral build-up. Water with higher mineral content (“hard water”) tends to react with castile soap in a way that leads to additional buildup. If you have hard water or notice your animal (or your humans!) aren’t getting as clean as you’d like, try adding some vinegar to your pet or human castile soap recipes. About ¼ cup of either distilled white vinegar or apple cider vinegar should be enough to counteract the buildup and don’t worry, the vinegar smell won’t linger once you’re finished rinsing.
  • If your pet is extra dirty or odorous, dissolve 3 tablespoons of baking soda into the water before adding your castile soap. (We wouldn’t necessarily add the baking soda AND the vinegar in the same recipe unless you are trying to have a fun chemistry experiment at home! These two ingredients have opposite pH values, which leads to high reactivity and makes them both less effective when combined. The chemical reaction is non-toxic and can be cool to watch, though!).
  • If your pet struggles with dry skin or fur, add one tablespoon of vegetable glycerin or olive oil to your shampoo recipe (you can also add this ingredient to your body wash if your human family is struggling with dry skin!).

Step 2: Add ½ cup of liquid castile soap to the container of water (and optional ingredients, if used), and shake until mixed.

Note: You will likely notice that the solution turns white once the soap is added – this is to be expected. Put the lid on your container, make sure it is sealed tightly, and shake the mixture until thoroughly combined. The shampoo will settle upon standing, but just give it another firm shake before use.

Optional Final Step: Add a minimal amount of pet-safe  essential oils for scent.


We make a lot of notes, but this is one that we simply can not stress enough: Use an abundance of caution any time you choose to use essential oils on or around any animals.

Our pets’ sense of smell can be anywhere from ten to one hundred times stronger than our own. Many essential oils are irritating to them, and some can be fatally toxic. Unfortunately, we cannot provide an exhaustive list of safe or unsafe oils because not all species of animals are sensitive (or not sensitive) to the same oils.

For example, birds have a highly sensitive respiratory system that can be easily overwhelmed, and cats have a unique metabolic function that can cause toxins to accumulate in their livers. No essential oils are considered safe for use on birds or cats, but some are so exceptionally dangerous that just diffusing them in a room or wearing them on your own body can lead to harmful exposure for these species. In the case of aromatherapy, it may be safe in some circumstances to use certain hydrosols ( – which are water-based plant distillates – around these animals because they are much less concentrated than their essential oil counterparts. But even hydrosols have not been established as safe for use directly on the animal themselves, and should be avoided in topical applications such as pet shampoos for birds or cats.

If you decide to add essential oils to your pet shampoo, the first rule is to choose only 100% pure essential oils from a reputable source and avoid any oils that are marketed as “fragrance oils”. These inexpensive oils are usually synthetic and are not safe for use in products that go in or on your or your pet’s body.

Secondly, make sure not to use too much. Our rule of thumb is to aim for no more than 2% TOTAL essential oils by volume, which usually comes out to only a drop or two for the whole batch. Keep this in mind if using any ingredients that are already scented.

Always check with your personal veterinarian first to make sure any scents you choose are safe for your particular animal. The following is not a comprehensive list of all the essential oils that could be potentially dangerous to your pet, but is a suggestion of popular scents that are known to be more likely to cause adverse reactions in many animals, especially dogs, cats and/or birds:

  • Anise
  • Birch
  • Bitter Almond
  • Camphor
  • Cassia
  • Clove leaf and bud
  • Cinnamon
  • Citrus
  • Crested Lavender
  • Eucalyptus (toxic for cats)
  • Garlic
  • Horseradish
  • Hyssop
  • Juniper
  • Lavender (toxic for cats, possibly safe for dogs)
  • Lemon (toxic for cats)
  • Mustard
  • Nutmeg
  • Orange (toxic for cats)
  • Oregano
  • Palmarosa (toxic for cats)
  • Pennyroyal
  • Peppermint (possibly safe for dogs)
  • Pine
  • Rosemary
  • Savory
  • Sandalwood (toxic for cats)
  • Sweet Birch
  • Tansy (all forms)
  • Tea Tree
  • Thyme
  • Vetiver (toxic for cats)
  • Wintergreen
  • Ylang Ylang

Time for a bath!

Even though castile soap is fantastic for sensitive skin and works wonderfully to combat problems like itchy dermatitis because it is an all-natural soap, it is not able to be prepared in a “tear-free” formulation like many modern commercials (synthetic) pet and baby shampoos tend to be. Take care to avoid getting any suds in your pet’s eyes and ears, and especially for our floppy-eared friends, make sure that their ears are completely dry after bathing to avoid infection.

Also remember that dogs and many other animals have a higher baseline body temperature than we humans do, and can therefore be uncomfortably chilly in water that feels warm to us. We always want to avoid making our animals uncomfortable as much as possible, because that is when accidents can happen. Make sure you are using water that is warm enough (but not too hot!) for your pet, and try to keep them relaxed by avoiding any loud or startling sounds or distractions during bath time. Creating a positive bath experience will go a long way towards making everyone happier when it’s time to do it again.

More tips for…


This shampoo mixture can be safely stored for several months, so feel free to make it in larger batches to keep on hand. Just make sure to store it in a place that is not accessible to pets or children, as consuming the soap will cause an upset stomach. Also remember that separation of the shampoo’s ingredients is expected, so just shake the container thoroughly to recombine before using.

using castile as pet shampooFleas

Castile soap only works to kill fleas when it comes into contact with fleas on a wet animal. Once the animal is dry, the castile soap no longer provides any flea-killing or preventative action. Castile soap also does not kill flea eggs.

If you are trying to manage an existing flea problem, the best solution is to wash all of your pet’s toys and bedding using liquid castile soap and bathe your pet with castile shampoo frequently to kill off new fleas as they hatch. Check with your vet first, but you may also be able to add a small amount of lemongrass essential oil to your castile soap pet shampoo for extra flea-fighting power.


Are we supposed to bathe our cats? Don’t they meticulously bathe themselves? Will they even let us bathe them? (That last one we aren’t so sure about.)

Generally speaking, your cat will keep themselves clean enough, but there may be times when they get into something too gross and need your help. Let’s be honest, it’s going to be up to the cat whether or not you’ll be allowed to bathe them, but as long as you are careful and conscious of your pet’s comfort, there is (hopefully!) no harm in trying. (Maybe wear long sleeves just in case…)

Some feline breeds (or specific individual cats) may require more frequent bathing by their humans due to a range of reasons from health concerns to personal habits. Talk to your vet to find out what is best for your pet, but usually, you shouldn’t need to bathe most cats more than about once a month, if at all.

Keep in mind our notes about feline sensitivity to essential oils, and avoid using any such products when bathing your cat.


Most birds prefer to handle their own bathing. Give your bird access to a shallow container of plain, clean water for this purpose. You can also keep fresh plain water in a misting bottle for an occasional refresh.

If your bird gets into something that doesn’t seem to be coming off their feathers, you can gently bathe them with a mixture of unscented castile soap diluted with water. Ask your vet before adding any other optional ingredients or fragrances.

Check out our brand new Liquid Castile Soap in the “Soap + Shampoo Bars” section of our shop. This is the latest addition to our Lactosoapcillus line of all-natural probiotic and vegan soaps, and you can count on it to deliver all of the same skin-loving probiotic benefits that you have come to love. We are happy to offer four customer-favorite, all-natural scents of liquid castile soap, including “Frankincense, Tea Tree & Lavender” “Lavender”, “Patchouli”, and “Peppermint and Eucalyptus”, as well as an “Unscented” option. (For the purpose of making pet shampoo, we highly recommend going with our unscented option!)

If you have any questions, suggestions, or feedback, as always please don’t hesitate to reach out to us.

Happy Bathing!

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