My 13-14 week old guinea pigs Piglet & Sugar both have been suffering from a URI (at least that's what the vets have said). They have now been on 4 different antibiotics. Bactrim, Baytril, Doxycycline and currently now Chloramphenicol (which was started last night but they seem to be sneezing more all a sudden). They are also taking benebac with there food an hour before the antibiotics. What I am wondering about is if they are allergic to something in our apartment (an old early 1900s home turned into 4 apartments). My BF and I have been having what's feel like a non stop "cold" or some nose sinus or coughing issues since we have moved here (march of this year). I am thinking something in our apartment is causing us to have these issues and possibly our guinea pigs too. I have looked for mold but haven't found any. Since none of the antibiotics have seemed to rid our piggies of the sneezing I am almost convinced they are allergic to something here. Please help.