Here's just an antibiotic treatment explanation I came across;
Since 90% of cases are viral in origin and we have no antibiotics against viruses, it seems odd that most feline upper respiratory infections are treated with anti-bacterial medications. The reason for this is that it is common for these viral infections to become complicated by secondary bacterial invaders. The antibiotics act on these. Further, the next most common infectious agents (after herpes and calici) are Chlamydophila felis (formerly known as Chlamydia psittaci) and Bordetella bronchiseptica, both organisms being sensitive to the tetracycline family (such as doxycycline). For this reason, when antibiotics are selected, tetracyclines and their relatives are frequently chosen. (Since tetracycline use can permanently stain the teeth of immature animals, these medications are generally not chosen for younger pets.) Oral medications, and/or eye ointments are commonly prescribed.
For congestion, some human nose drop products can be used for relief. Consult your veterinarian before attempting any sort of home treatment. Other therapies frequently employed include low doses of interferon-alpha (to generally stimulate the immune system) and oral lysine supplementation (which interferes with herpesvirus reproduction).
For younger kittens that are infected, often the most significant factor in their throwing off infection is maturation and gaining a more effective immune system with growth.
You may want to talk with your vet about that. Some sources say to defiantly use antibiotics, however these will not get rid of the URI itself, so just talk this over with your vet. From my understanding, antibiotics cannot get rid of the URI, but help to prevent secondary illnesses that can result from URI's like pneumonia.
Also, here are some natural remedies you may want to try or assist with other medical treatment for symptomatic relief;
As with a child's cold, you simply provide as much relief from symptoms as you can while allowing the virus to run its course. We put cats with URI on an antibiotic to prevent secondary infections like pneumonia from developing -- but antibiotics do not affect the virus itself. See your vet to get a supply. Keep the cat strictly indoors, of course, in a warm quiet room without drafts. Feed canned food--the "smellier" the better--in order to stimulate appetite. It is important to make sure adult cats eat at least a little bit every day. Wipe the eyes and nose as needed. Some cats, especially the short nosed ones, get so congested that they are really miserable, unable to breath, eat or drink or sleep comfortably. You can use a humidifier to make the cat more comfortable. You can also use Pediatric Neo Synephrine (not adult), 1 drop per nostril, morning and evening (for no more than 2 -3 days) to relieve the congestion. Never give a cat any "home remedies" without consulting your veterinarian.
Because URI is such a common shelter problem and other vets seldom encounter it, we are very familiar with techniques for nursing a cat through the disease. Please feel free to ask for our advice. You can call directly at 787-2500 ext. 804. Leave a message and we'll return your call as soon as possible. Be sure to take your cat to your vet and try not to worry. Remember how miserable a bad cold feels (and appears). With your care and attention, your new cat will undoubtedly be her normal self in a week or two.
Here are my sources if you'd like to visit their websites;
http://www.paws.org/cas/resources/fact_sheets_cats/respiratory.php
http://www.sheltermedicine.com/portal/is_feline_upper_res.shtml
