No, hairless cats are not hypoallergenic per se but if you are allergic to cats your reaction to a hairless cat may be less than it would otherwise be to a normal cat with a coat. I’ll explain why.
The allergen which causes people to be allergic to cats is the Fel d1 protein in the cat’s saliva. Normally this allergen is deposited on the cat’s fur in the saliva. The saliva dries and it flies off the fur with some hair creating dander which settles around the home causing the allergic reaction. So the underlying method of transmission of this allergen is through a cat grooming themselves using their saliva.
Hairless cats such as the Sphynx groom themselves like any other cat. As they have very little hair they deposit their saliva on their skin together with the downy hairs. The saliva dries in the same way, flies off and is deposited on household items including furniture just like any other cat. Therefore on the face of it a hairless cat will produce an allergic reaction in a person who is allergic to cats.
There are mitigating factors, however. This is because owners of hairless cat must wash their cat regularly. This is because the sebaceous glands in the skin deposit oils on it. These oils would normally permeate into the hair strands. But they rest on the skin where they pick up dirt resulting in the cat becoming grubby. You may have seen this in Sphynx cats i.e. a dirty appearance.
So you have to clean your Sphynx or hairless cat regularly which means you wash from the skin the cat’s saliva containing the Fel d1 allergen. In cleaning the skin like this it must mitigate the possibility of a person suffering an allergic reaction to the allergen because it is wiped off. This means that it does not fly into the atmosphere and land on objects in the home. To repeat, the dander as it is called is wiped off and kept from being deposited on objects. This is bound to produce a lower allergic reaction despite the fact that the basic elements for an allergic reaction are in place.
The benefit is that with hairless cats the possibility is reduced or mitigated. All domestic cats are not hypoallergenic, which means, incidentally, to produce a less severe allergic reaction. Being hypoallergenic does not mean that a cat will produce no allergic reaction. It’s a myth in my opinion that some cats are hypoallergenic. You will see claims on the internet that some cats are but I think you’ll find that it is untrue.
There are some variables such as unneutered male cats being the most likely to produce more of the allergen than a spayed female cat which means you are more likely to be allergic to unneutered tomcats. And I’m told that the Savannah cat is less likely to produce an allergic reaction by which I mean that the cat might be partially hypoallergenic. Some claim that the Siberian is hypoallergenic but this in anecdotal.
There is a food out at the moment which is said to be effective in reducing an allergic reaction. It essentially coats the allergen and prevents it taking effect. You can read about it by clicking here.