My two year old male cat is losing hair on a spot on his back next to his tail could it be allergies?

He is an inside cat that is never allowed outside. I have noticed that he is scratching his back a lot and has a very tiny scab where the hair is missing. I have not changed his food or any of my cleaning products. Could it also be because its spring? Taking him to the vet is not a problem but if it is something that will pass or get better on it's own.

I have checked for fleas, he DOES NOT have fleas.

a good rule of thumb is if you don't know what is happening to your cat and it's uncomfortable.and you can take him to the vet.

It could be flea dermatitis, but not being a vet I cant really say that it would definatley be that. It could also just be a hot spot. Either way if it is bugging your cat then take him to the vets, he made need an anti inflammatory. Have a check and see if you notice any fleas, I know you said he is an indoor cat, but the little blighters can get in your house any way they can imagine. If you do notice some flea dirt, get some spot on treatment from the vet first and use it, and see if it clears up. My cat had some scabs down her back, I bought some spot on, and it did clear up after a while. This would save on a trip to the vets.But its up to you. Only you know how badly it is affecting your cat.

HAHAHA no offence but you have no experience with cats do you. its not alergies, as you describe it it is fleas DEFINITELY if its at the base of the tail so get him some GOOD flea stuff like "Frontline" is the best and it works unlike alot of others that dont do anything or go to the vet and ask for some flea stuff

fleas like to hang out at the *** of animals and if its a bald patch at the base of the tail generally where the little curve from there rear to the tail is forming a 90 degree its from the animal biting which damaged the roots dont worry once you get rid of the fleas the hair will repair its self and it will grow back GOOD LUCK!!!

It sounds like mange mites. Does your cat also scratch his ears a lot? If so, check inside the ear for black waxy residue.
Mites tend to attack the poor animal in areas and the fur falls out in patches sometimes leaving scabs or raw wounds.
I would recommend buying some Revolution from your local pet store and treating him with that.

it sounds like ringworm to me,is a fungal infection and is very easily cleared up with cream you can get from the vets but can be passed to humans so i would take him soon

could be ringworm. I think that's what it's called. Vets, and have it checked for parisites on the skin. Tea Tree oil will help too.