Barefoot has the best kidney tincture. Go with distilled water NOT purified. Standard Process Renafood is a great product.
I would consider cleaning the colon and decongesting the liver. Also a good antiparasite protocol. The Basics program. Kidney health responds very favorably to cleaning the digestive system up. Most of the time that's all that's necessary.
Also, check you spine. Make sure your upper neck is squared away.