Patient w/ chronic kidney disease not on dialysis w/ serum P level <1.78 mmol/L. Dysphagia; swallowing disorders; severe GI motility disorders; active inflammatory bowel disease, major GIT surgery. Intestinal obstruction & ileus/subileus. Peritonitis. Assess regularly serum vit A, D, E & K status. Possible folate deficiency. Metabolic acidosis. Hypocalcaemia/hypercalcaemia. Hypothyroidsim. Not indicated for control of hyperparathyroidism. Long-term chronic treatment. Pregnancy & lactation. Childn <18 yr.