Why is my cat sneezing?

He seems perfectly healthy otherwise. Eyes clear, breath (when he’s not sneezing) just fine, appitite regular, lyies around the house like a lumpy rug just like he always did.

Should I rush him to the vet? Has he just become allergic to himself?

Any vet type information?

Is he sneezing constantly or just on occasion?
My cats randomly get the sneezes, but I think it is from dust and the like (the same things that make us sneeze).

I have never panicked at or a sneeze or two.

Most animals sneeze on occasion. If that is what you are seeing, no big deal. If the sneezing is more frequent, or accompanied by conjunctivitis, it is likely an upper respiratory virus. If there is no secondary bacterial infection (mucopurulent nasal discharge) it will likely resolve without treatment.