Arnica montana for pain relief

Question
I have a rex rabbit that's 8 years old.  3 years ago when I rescued her she had a broken leg that had not healed.  Through lack of use she developed bone loss and arthritis.  Acupuncture and Metacam successfully manage the pain but she recently developed a gi problem that my rabbit savvy vet and I can't seem to nip.  

Anyway, I'd like to take her off the Metacam since I read that it could prohibit the gi from recovering so I'd like to use another method of controlling the pain.  What are your thoughts on Arnica?  

Answer
Dear Lisa,

While metacam can cause renal problems, I have not heard of it causing GI problems.  What GI problem is she having?  Ileus?  If so, please see:

www.bio.miami.edu/hare/ileus.html

Metacam is supposed to be a Cox-2 inhibitor, so its GI effects should be rather mild. But if your vet is concerned about ulcers, consider adding famotidine to help prevent the acidity that often results from NSAIDs.  If the vet suspects there are already ulcers, then sucralfate can be very helpful.

I am not a fan of homeopathic remedies, as there is no real evidence to suggest they work.  So that's the word on arnica, in my opinion. (Arnica can't be administered in any quantity other than homeopathic dosages, as it is toxic.  And studies have shown that arnica is no more effective than a placebo at reducing pain.)

The real issue is getting to the bottom of why she is having GI problems, and that could take some detective work.  At her age, and with the bone loss already an issue, my suspicion would be molar spurs:

www.bio.miami.edu/hare/dental.html

but it could be any number of things, from bladder stones or sludge to arthritis pain, etc.  It could be those causing the GI problems, not the metacam.

I hope this helps.

Dana