Not sure how helpful this is to you, but my dog (with hip problems, and maybe arthritis too) weighs 70 pounds and gets 1 and a half tbsp/day of glucosamine... sounds like you're giving your dog only half a tbsp/day.
I don't know how much your dog weighs, and I've never tried chondroitin (though I know it helps with glucosamine absorption...) but I figured that it wouldn't hurt to post it.
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