rat upper respiratory infection

Question
my rat is 2 months old, and just last weekend he began to sneeze and have
red discharge dry on his nose. Realizing the symptoms i knew it was a respiratory infection. I called my vet and brought him in 3 days ago...the vet
gave him doxy and baytril combo.... i dont know if there has been any
improvement because he is still sneezing and has less, but still some dry
discharge on his nose ,.... and his new symptom is he is itching more often
then before.... hell scratch his head lick his foot and then scratch his back and  
lick his foot and then repeat this 2-3 times.......

Could he be having an allergic reaction?  as in hives, even though i dont see
them under his fur and his tail looks normal??

should i have the vet change his meds?  if so to what?

& could his coat color have any affect on his reaction to meds...because he is
carmel colored with a white belly  but his eyes are brownish and red-
maroonish tint in the light....

any helpful advice would be great!!

happy thanksgiving!!!

Answer
I would drop the doxy, continue the baytril and add either cefa-drops or my second and third choices would be keflex or amoxil.  This will cover secondary infections.

To be honest, I dont like using baytril in rats under 4 months old, but chances are if your vet is not an exotic specialist, he will frown upon what I said and give it anyhow. You can read more about why on my site, here:

http://www.freewebs.com/crittercity/mycoplasmosispage.htm

He shouldnt have any allergic reaction but if he did, it would be more along the lines of diarrhea, but sometimes they do have excessive itching.  You would probably see a combination of both if he had allergies to the meds.