Funny how some dogs have a mud radar. They sniff out hidden muddy puddles and have a splash-tastic time, with disastrously dirty results. Anyone who's ever returned from a walk, planning how to get a bath running without the dog shaking mud up the walls, will have empathy with just how dirty dogs get.
But when you reach for their special doggy shampoo and the bottle is empty, what's to be done? Can you use human shampoo or is it a complete no-no? Let's find out.
Two Legs vs Four Legs
People and dogs are different, and not just because of the number of legs they each have.
People and dog skin is different. For example, human skin has a pH of around 5.5 - 5.6, which is to the acidic side of the scale. However, dog skin is more neutral, which a pH of 6.2 - 7.1. In addition, human skin has 10 - 15 layers of skin cells (think of this like layers of bricks in a wall), whilst dog skin is much thinner at 3 -5 cell layers, and cats thinner still at 1 - 3 layers.
This means that human shampoo is altogether harsher than pet products. It's designed to work with acidic skin which can tolerate a greater stripping of oils. Also, the added thickness of human skin makes it more resilient to water loss and the scouring effect of some human shampoos. In short, what's good for people is likely to cause dryness and irritation for pets.
In addition, dropping the natural pH of a dog's skin, is akin to stripping away it's natural protection and weakens its immunity. This provides an open door for the bacteria and yeasts that live on the surface of the skin, to grow out of control and cause skin infections. In short, human shampoo is too drying and abrasive, and set's the dog up for skin infections.
One Size Does NOT Fit All
The physical appearance of a product has very little to do with how it works.
Using a human product because it shares the word 'shampoo' with a doggy equivalent, is like taking a birth control pill to treat a migraine, because headache tablets are also 'pills'.
Be aware that dog shampoos are highly sophisticated, and can be effective therapy for various skin conditions. When you shampoo a dog, you present the skin surface with molecules that can heal or do harm. The upshot is that human shampoos harm, whilst pet shampoos heal.
Examples of the ingredients in veterinary approved shampoos include:
Selenium sulfide: Removes doggy dandruff and treats scaling
Chlorhexidine: An antiseptic valuable for treating bacterial skin infections
Miconazole: An antifungal that helps treat ringworm and yeast overgrowths
Oatmeal or aloe vera: Moisturizing and soothing for itchy skin
A Word about Baby Shampoo
Of all the human shampoos, baby shampoo is slightly different. Tear-free formulations in particular, are more neutral than adult products. Their pH 7 respects the delicate nature of an infant's skin and eyes, and this makes it less likely to be strongly astringent effects on your fur-baby's skin. Although not ideal, especially as these shampoos are often surprisingly full of chemicals, it may provide an emergency option as a one-off for the super dirty dog.
What are the Practical Implications?
Your dog indulges in a mud bath and needs a top to toe clean before walking on a cream carpet.. However, you discover the dog shampoo is all used up and you forgot to re-order. What's to be done?
Ok, from a practical perspective, a one off use of a tear-free baby shampoo isn't the end of the world. At least the pH of baby shampoo is sympathetic to the dog's skin and there's less risk of irritation or stripping away precious oil.
In this example, the benefits of washing away bacteria-laden mud (with the potential to cause dermatitis) are outweighed by the slight chance of skin irritation. With one-off use, the risks are minimal, but go and restock with your favorite doggy shampoo before their next bath.
But remember, dog shampoos aren't a gimmick. They can and do make a real difference to the health of your dog's skin, so keep your shampoo for personal use and just this once don't share with your best buddy, but keep a stock of their own product.