My lab is 10 and has arthritis I bought a natural herb called devils claw, it is suppose to be good for pets and humans, I bought it but not sure if its really good to give to her. She weighs 76 lbs the capsuls are 170 mg of devils claw extract and 340mg of devils claw. how much should I give her and will she be ok with it, she also take a thyroid med. Thank YOu….