I've mixed results with it. Helped me a couple of years, so it seemed, and then .... no effect noted. Used in conjunction with golden seal. Nowdays I stick to zinc tablets with bilberry, lots of clear warm liquids.
Two months back started taking cod liver oil and vitamin B complex for carpal tunnel. Helped *greatly* in conjunction with hand exercises and learning to use mouse southpaw -- use either hand now. Side effect seems to have been that I missed two or three of the colds and flus that have occurred around me. Had been pretty susceptible prior. Believe it was the cod liver oil.
Valid comment. I should have considered my wording more carefully.
Have you tried MSM for your hand? It seems to work wonders for connective tissue or arthritic problems. Good for overall health too. Maybe carpal tunnel as well (or maybe not, but there is no risk in any dosage). The powder tastes bad, but the pills are expensive and several gram or larger doses daily are needed.