It is usually a viral thing- For the most part it just has to run its course
Alot of times vets will prescribe anti-biotics as a precautionary to prevent any opertunistic (sp)infections. Are they really bad? How old are they? Kittens and older cats, or cats with existing health problems are the most vulnerable. My recent addition, Murphy , had a URI ( upper respitory infection ) when I first brought him home. I had to take him to the vet because he had pink eye- they put him on eye ointment, about a week later his sneezing increased so I brought him back and they put him on clavamox ( antibiotic) but he is fine now THANK GOD! My resident cat Chichi never really got sick, She sneezed a couple times, had runny eyes for a day or 2 but she never got ill like Murphy did. If they have goopy ( white-or green) stuff coming out of their eyes, sneezing out gunk, boogers ( Soooo sorry for the grossness!) I say take them in ASAP. But if the eye discharge is'nt goopy, lets say just slightly watery, and they are lightly sneezing-no mucus I would call avet and get their opinion, but ultimatley (sp) it will have to run its course. But if the eye discharge goes from watery to goopy take them ASAP or if they are having difficulty breathing. GOOD LUCK let us know how they are doing!