antiviral medication

I have  5 month old kitten who we rescued from a sanctuary.  She has her right eye removed when she was 8 wks old. she had a long time URI that they had her on clavamox for.  We didn't know she was sick until we brought her home.  She sounds really congested.  Activity is absolutely normal!  ******* hyper than any kitten should be.  lol  I took her to our Vet to be checked out.  They did another round of clavamox & had no improvement.  So the Vet started her on Pred 1mg/ml once daily along with Famaciclovir 9mg 3 times daily.  We have seen no improvement & its been just about 2 weeks since we started.  The vet thinks she is gonna have a lifetime of breathing issues.  Anyone have any idea on how fast the meds should take before I seen any changes?  

Any thoughts are welcome!!!

Did the vet mention feline herpes? That's what it sounds like might be contributing to the lengthy recovery period.  To help with the congestion, you might try steaming her in the bathroom.  Just get the bathroom nice and steamy and then sit in the bathroom with her while the steam dissipates.  You can also try plain baby saline nose drops.  If you're in the US, look for Little Noses brand.  If she's got any nasal discharge, you can ask the vet to do a culture and sensitivity test to find out what kind of infection you're dealing with and what medication will best treat it.