Homemade dog shampoo: the oatmeal bath that's actually safe

Key points

• A dog's skin has a more neutral pH than human skin and is thinner, so human products can disrupt it.
• Baby shampoo, dish soap and essential oils aren't good choices for washing a dog.
• A colloidal oatmeal bath soothes itching and is safe, but it doesn't replace dog shampoo when they're dirty.
• Most dogs only need a bath every 4-8 weeks or when they get dirty.
• Drying all the way down to the skin prevents hot spots, especially in dogs with dense coats.

A homemade dog shampoo sounds like the most natural option, but the recipe we published here years ago, with baby soap and lavender essential oil, wasn't the best idea for their skin. A dog's skin is thinner than ours and has a different pH, and what's gentle on a baby can dry out or irritate a dog.

What you can do at home, and it works very well, is a soothing colloidal oatmeal bath: just finely ground oats and warm water. It's a complement to a shampoo made for dogs, especially for itchy or dry skin. Here's how to make it, how to bathe your dog step by step and how often to do it.

Why your dog's skin isn't like yours

Human skin is slightly acidic, with a pH of around 5.5. A dog's is more neutral, between 6.2 and 7.5 depending on the area and the breed. On top of that, its outermost layer is much thinner: just a few layers of cells compared with ten to fifteen in ours.

That's why human products, baby shampoo included, can disrupt the barrier of a dog's skin: they dry it out, encourage dandruff and itching, and open the door to bacteria and yeast. Dish soap, which some people recommend for grease, is even harsher. And essential oils like lavender or tea tree irritate the skin, and some are toxic if the dog licks them.

The safe approach: dog shampoo plus an oatmeal rinse

For washing, use a shampoo formulated for dogs, mild and fragrance-free if their skin is sensitive. If your dog has a skin condition, the vet may prescribe a medicated one. The homemade step comes afterward: a colloidal oatmeal rinse that leaves the skin calm.

Colloidal oatmeal is oats ground so finely that, when mixed with water, they stay suspended and the water turns milky. It contains compounds (avenanthramides, beta-glucans) that help soothe itching and hold moisture in the skin. It's the same ingredient used in human dermatology for atopic skin.

How to check the oats are ground finely enough

Stir a tablespoon into a glass of warm water: if the water turns white and milky and the oats don't sink straight to the bottom, it's ready. If you can see pieces, grind it some more.

How often to bathe a dog

• Most dogs: every 4-8 weeks, or when they roll in something or smell bad. If they've been out in the countryside, use bath time to check for ticks.
• Dogs with oily coats or that live outdoors: they may need it more often, with a mild shampoo.
• Dogs with skin problems: whatever the vet prescribes; sometimes twice a week with a medicated shampoo.
• Puppies: only when needed and with a puppy shampoo.

Between baths, brushing is what keeps the coat cleanest. And if it's only their paws that smell, our homemade dog deodorant explains how to clean them without a full bath.

Drying matters more than you'd think

A dog with a dense or double coat (German Shepherd, Golden Retriever, Husky) can stay damp next to the skin even when it looks dry on the outside. That trapped moisture encourages hot spots, red oozing sores that can appear within hours. Dry with a towel by pressing, not rubbing, and finish with a hair dryer on warm, about 30 cm (12 in) away and keeping it moving. Pay attention to the armpits, groin, between the toes and the ears.

More ideas in homemade dog care.

What you need

• 80-100 g (about 1 cup) plain rolled oats, with no sugar or flavorings
• Blender or grinder
• A tub or the bathtub
• Dog-specific shampoo
• A brush suited to their coat type
• Two towels and a hair dryer

Step by step

1. Grind the oats

   Blend 80-100 g (about 1 cup) of rolled oats until they're a very fine powder, like flour. Do the glass test: the water should turn milky.

2. Brush before wetting

   Work out any tangles while the coat is dry. Wet knots tighten and become impossible to remove.

3. Wet with warm water

   The water should be about 37 °C / 98 °F, as for a baby. Wet them down to the skin starting at the neck and leaving the head until last, without getting water in the ears or eyes.

4. Wash with dog shampoo

   Apply the shampoo, massage against the direction of the coat so it reaches the skin, and rinse thoroughly. Leftover shampoo is a common cause of itching.

5. Rinse with oatmeal

   Dissolve the oats in a tub with 4-5 liters (about 1 gallon) of warm water and pour it slowly over their body, massaging it in. Leave it on for 5-10 minutes.

6. Rinse lightly and dry

   Pour over a little clean water to remove oat residue from the coat, press dry with a towel and finish with a warm hair dryer all the way down to the skin.

Frequently asked questions

Can I wash my dog with baby shampoo?

It's not ideal. Baby shampoo is gentle on human skin, but it's formulated for a more acidic pH than a dog's skin, which is also thinner. Used now and then in a pinch it doesn't usually cause problems, but regular use can dry out the skin and lead to itching or dandruff. A mild dog shampoo is a better choice.

Is oatmeal good for dogs' skin?

Yes. Colloidal oatmeal, meaning very finely ground oats, helps soothe itching and keep the skin hydrated thanks to its avenanthramides and beta-glucans. It's useful for dry, sensitive or mildly itchy skin. It won't cure dermatitis or an allergy, but it's a safe complement to shampoo and to whatever treatment your vet prescribes.

How often should you bathe a dog?

Most dogs need a bath every four to eight weeks, or when they get dirty or smell bad. Bathing more often with the wrong shampoo can dry out the skin. Dogs with skin conditions may need more frequent baths with a medicated shampoo, always following the vet's instructions. Between baths, brush them regularly.

Can I use vinegar to bathe my dog?

We don't recommend it. Vinegar doesn't clean better than a dog shampoo, it can sting on any cut, scrape or irritated spot, and its smell is very unpleasant to a dog's nose. It hasn't been shown to work against fleas or ticks either. If you're after something soothing, a colloidal oatmeal rinse is a much gentler option.