hi...sorry there is not much activity or a holistic Vet on this forum any longer. I am a cat owner who does like to treat naturally whenever possible, I know for cats a product thats well known and used for this type of problem and I can't see why it couldn't be used for bunnies too....(?)
Its an amino acid that strengthens the immune system so they can fight off this on their own, its usually viral in cats... but if in doubt at all please speak to a Vet first.....could also be that she has a small particle irritating her nasal passage (?)
for cats with an acute attack we use 500mg for a week, than down to 250mg following for a few weeks. and for cats its important to use the brand with NO additives...just pure lysine. I will give you a link to where I order mine from...because locally its sometimes hard to find the same brand.
I also suggest you post this question on the Animal Health forum, where a Vet Dr. Redford, can tell you if its ok to use this for bunnies too, but I can't see why not. I will also give you a link to that forum. good luck♥
http://www.iherb.com/Carlson-Labs-L-Lysine-Amino-Acid-Powder-100-g/13608
http://www.medhelp.org/posts/new_with_new_subject?forum_id=112