Safety and efficacy of nicotinamide in the management of hyperphosphatemia in patients on hemodialysis

Hyperphosphatemia is an important modifiable risk factor for death and cardiovascular events in patients on hemodialysis (HD). As nicotinamide has been shown as an inhibitor of sodium-dependent phosphate co-transport in rat renal tubule and small intestine, we examined whether nicotinamide reduces hyperphosphatemia in patients undergoing HD. The study was conducted in 30 end-stage renal disease (ESRD) patients [20 (66.7%) males and 10 (33.3%) females; mean age 54 ± 14.9 years] undergoing twice/thrice weekly HD for more than 3 months. Patients on other phosphate binders were given a 2-week wash-out period. Nicotinamide 250 mg capsules were given twice daily for 25 patients with serum phosphorus greater than 5 mg/dL and thrice daily for 5 patients with serum phosphorus greater than 8 mg/dL immediately after food for 8 weeks. Serum phosphate and calcium levels were estimated every month prior to HD session, and complete blood count, blood sugar, renal profile, liver function tests were estimated at beginning and end of the study. Patients were regularly monitored for side effects. There were significant decreases in the serum phosphate (6.85 ± 1.35 mg/dL at the baseline to 5.74 ± 1.18 mg/dL at the 4(th) week and to 4.54 ± 0.86 mg/dL at the 8(th) week), the serum calcium-phosphorus product (57.8 ± 12.21 at the baseline to 48.3 ± 10.71 on 4(th) week and to 38.201 ± 8.21 at the 8(th) week), and alkaline phosphatase levels (130.23 ± 50.13 IU/L at the baseline to 116.40 ± 48.27 IU/L after 8 weeks) on treatment with nicotinamide (P < 0.001). Other parameters remained unchanged. Watery stools reported by seven patients resolved during the course of the therapy. Nicotinamide is safe, cheap and effective in controlling serum phosphorus, Ca × P product and alkaline phosphatase levels in patients on maintenance HD.