cat skin

Question
I've been trying to get a hold of useful answers, but still no luck. I have a Sphynx cat and he has a dark layer on top of his skin, not filmy, no different in texture as his normal skin, but does not look normal. I bathe him about every 2-3 weeks.  I've looked it up and it seems to be a film from the oil build-up. I wash him with a soft tooth brush with baby shampoo when I bathe him, but still doesn't come off. Is there anything that will take it off? What kind of wash should I bathe him with if not baby shampoo? Toothbrush? Please help. Thankyou.

Answer
You should never bathe a cat or dog with any human shampoo. The PH is off and it exposes the skin to infections that way.
One thing that could be happening is that the very act of shampooing this cat with human shampoo, which is basically a fairly harsh detergent, is causing his skin to protect itself with a darkened layer called hyperkeratosis and hyperpigmentation. I haven't found any kind of skin disease directly related to the Sphinx so I am just guessing.

You didn't mention whether this was a new occurrence or something you have been dealing with since you have had the cat. I also don't know the age of the cat.
I can't imagine bathing a Sphinx cat, hairless or not, as often as you are is any better for them as it is for a haired cat. We don't ever recommend bathing a cat. Their grooming is enough to keep them clean and healthy.

The oil buildup you are referring too is also there to protect your cat's skin from the elements. I have worked on many Chinese Crested's and they not only have the oiliness to their skin but they also grow larger and larger pigment spots all over their bodies as they age.

You might want to look up Sphinx breeders and see what they can tell you about the condition or better yet go to the vets and ask them what it is.
While you are there get some shampoo made for a cat's skin PH. Your cat will thank you.