Calcium in the treatment of diarrhoea and hyperoxaluria after jejunoileal bypass for obesity.

Fourteen patients with jejunoileal bypass for obesity were treated for one week with a calcium supplement of 3g daily. During this period diarrhoea was significantly (P < 0.005) reduced by 23 per cent (97 per cent confidence limits: 7-46 per cent). Ten of the patients had hyperoxaluria (median value 961 mumol/24 h; range 633-2742 mumol/24 h). The treatment with calcium significantly (P < 0.005) decreased the concentration of oxalate in urine by 23 per cent (98 per cent confidence limits: -5-+54 per cent). The calcium supplement did not increase urinary calcium-excretion rate or albumin-corrected serum calcium.