If you take him into a steamy bathroom you will have to watch him very carefully and if it isn't helping get him out of there immediately!! It can help easy symptoms for the short term or it can add fluid to the lungs and make it harder for your rat to breath.
A tiny piece of dark chocolate (not milk chocolate) might also help in the short term
He needs the antibiotics changed immediately.
When antibiotics do not start to help within 2 to 3 days, then different antibiotics or combos need to be tried.
Please take him back to the vet in tomorrow.
What is he on?
How much does he weigh,
what is the strength of the med mg/Ib or mg/grams,
and how much is he getting?
I would suggest baytril + azithromycin (10mg/Ib, available from pharmacies by prescription from your vet) orally, twice a day for at least 6 weeks if it helps .... or these two meds + dozy
It is difficult for him to breath and eat at the same time so feed him soft foods such as blocks soaked in water to make mush, cooked quinoa, organic soy infant formula (or ensure) thickened with baby cereal, baby food etc ......... and make sure he is hydrated as dehydration kills
If you gently pull up the skin on the back of his neck and it snaps back into place then he is well hydrated, otherwise he may be dehydrated ..... you can tempt him with foods containing a lot of fluids such as previously mentioned foods. You can also give him fluids one drop at a time by syringe (no needle on it) into the side of his mouth - if given straight in, it could go into his lungs
Here is a link to a hydration fluid
http://www.ratshackforum.com/forum/showthread.php?t=8730
good luck
hope he is soon doing better
for humane euthanasia see
http://www.ratshackforum.com/forum/showthread.php?t=7652
