Oral sodium polystyrene sulfonate (SPS) barely lowers serum potassium levels in hospitalized patients with mild hyperkalemia, a new study finds.
In light of its questionable benefit, investigators further suggested the cost and potential adverse effects of SPS, a potassium-binding resin, make it inappropriate for hyperkalemia treatment.
Josh Batterink, BSc (Pharm), of St Paul’s Hospital in Vancouver, British Columbia, and colleagues compared outcomes among 138 patients with a serum potassium level of 5.0 to 5.9 mmol/L during a hospital stay. Of these, 66 received a single dose of oral SPS (15 or 30 g). None had chronic or acute renal failure or recent changes in medication or diet that would have affected their potassium levels.
Results published in the Canadian Journal of Hospital Pharmacy (2015 Jul-Aug;68(4):296-303) showed that the average change in serum potassium after 6 to 24 hours was 0.44 mmol/L in the treated group versus 0.58 mmol/L in the untreated group. Although this 0.14 mmol/L difference was statistically significant, “the small treatment effect observed in this study may not be clinically important,” stated the investigators. There was no difference in serum potassium levels by dosage of SPS. Future randomized trials are needed to validate the findings.