Niacin and analogs for phosphate control in dialysis--perspective from a developing country.

Hyperphosphatemia is an important modifiable risk factor in the dialysis population because it is linked to increased mortality. Existing phosphate-reducing agents either increase the risk of vascular calcification or are costly with high pill burden. Niacin shows promise as a cheap drug with low pill burden and a novel mode of action. Niacin and its metabolite nicotinamide inhibit the small intestinal sodium-phosphate cotransporter. Approximately 50% of intestinal phosphate absorption occurs through this route under physiological conditions. Studies performed on the dialysis population with niacin and nicotinamide have shown significant phosphate reduction with lowering of the calcium-phosphorus product. The well documented increase in serum HDL levels may also offer survival benefits. Side-effects include flushing, which is controlled with aspirin, diarrhea, and thrombocytopenia, which may be treatment-limiting. Niacin is cheap and phosphate reduction can be achieved by administration of one or two tablets per day. These factors will boost compliance in developing countries. Further basic research and large-scale clinical trials are needed in this field.