1. Calcium Oxalate Stones - These are developed by elevated urinary calcium. This is usually the result of excessive calcium absorption, but not always. The prevention and treatment plan for this type of kidney stone is to consume at least 12-16 cups of fluid (water, tea, coffee, wine, and beer…apple and grapefruit should be avoided) a day. Thiazide diuretics help reduce urinary calcium by enhancing calcium REabsorption in the kidney tubules. Other medications include cholestyramine (which reduces oxalate absorption) and allopurinol (which reduces uric acid production in the body). Diet Therapy includes adjustments in calcium, oxalate, protien, and sodium intakes. Your friend should consume adequate calcium from food sources (800 to 1200 mg/day) because dietary calcium combines with oxalate in the intestines, reducing oxalate absorption and helping to control hyperoxaluria (elevated urinary oxalate levels). Controversely, low-calcium diets promote oxalate absorption and higher urinary oxalate levels. Foods high in oxalate should be restricted because dietary oxalate contributes to urinary oxalate content. Email me if you’d like a list of foods high in oxalate. As high protein and sodium intakes increase urinary calcium exrection, moderate protein consumption and sodium restriction are advised.