by Michael J. Fixler, D.V.M.
Adobe Animal Hospital
Scottsdale, Arizona
(pic courtesy of http://petswelcome.com)
Many dog owners have heard over and over that the pH (acidity) of canine skin is different than that of Human skin and, therefore, we should be using different shampoos, conditioners, and treatments for our furry friends than we would for ourselves.

This is true – the pH of canine skin ranges from 6.2 to 7.4 (roughly as neutral as pure water) while human skin has a significantly more acidic pH of 5.5 to 5.6 (some reports state as low as 4.0!).   For this reason human skin products are generally much more acidic than those formulated for dogs.

Acidity, however, is not the only difference between your skin and your dog’s.

Your dog’s epidermis (the protective layer of the skin) is only 5 cells thick as compared with human skin which can be 15 cells thick.  This characteristic requires that we use more delicate detergents and less frequent bathing when it comes to our pets (no more than once weekly unless skin disease is present or they have just taken a roll in the mud).
Canine and human hair and hair growth cycles are also different.

Multiple hair shafts emerge from each canine hair follicle as opposed to human follicles that only produce a solitary hair.  Human hairs remain in anagen (the growth phase) for 2-6 years where certain dog breeds have a fleeting anagen phase resulting in frequent shedding.

The bottom line is that even though you and your pet have numerous similarities, do not assume that you are identical.  You dermatological physiologies differ and as a result so do too your dermatological needs.