i have never had any kidney trouble from taking vitames or amino acids. what you are probably feeling is muscle spasm in the low to mid back. this is one of the first symptoms of jones" coming to visit. either baclofen (a neuro muscle relaxer) or a benzo such as valium, or both preferably. to be on the safe side, monitor your body temp for mid to high grade fever. w/d causes a slightly elavated bod