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Pretreatment of infant formula with sodium polystyrene sulfonate : focus on optimal amount and contact time
Jean-Christy F Cameron1, Dana Kennedy, Janusz Feber
1School of Pharmacy, University of Waterloo, Waterloo, ON, Canada.
Insights
Pretreating infant formula with sodium polystyrene sulfonate (SPS) effectively reduces potassium. Optimal results were seen with 10 mL of SPS, with no significant difference between brand and generic products or contact times.
Area of Science:
- Pediatric Nephrology
- Clinical Chemistry
- Pharmaceutical Science
Background:
- Limited effective and safe options exist for managing hyperkalemia in pediatric patients.
- Oral or rectal sodium polystyrene sulfonate (SPS) has potential adverse effects, and dietary potassium restriction can impact nutrition.
- Pretreating infant formula with SPS shows promise, but optimal dosing, contact time, and product comparisons are lacking.
Purpose of the Study:
- To evaluate the efficacy of different quantities of brand-name and generic SPS in removing potassium from infant formula.
- To assess the impact of 1-hour versus 24-hour contact times on potassium removal and sodium levels.
- To compare the effectiveness of brand-name and generic SPS products in formula pretreatment.
Main Methods:
- Infant formula was pretreated with four different volumes of SPS, measured in milliliters.
- Potassium and sodium concentrations were measured in formula samples after 1 and 24 hours of contact time.
- Brand-name and generic SPS products were tested to determine any differences in efficacy.
Main Results:
- Potassium levels decreased in all treated samples, with the most significant reduction observed with 10 mL of SPS.
- Sodium levels increased in pretreated samples, exceeding the reduction in potassium levels.
- Contact time (1 vs. 24 hours) did not affect potassium removal or sodium increase; no differences were noted between brand and generic SPS.
Conclusions:
- The potassium-removing capacity of SPS in formula pretreatment plateaus beyond 20 mL.
- This study establishes an effective protocol for pretreating infant formula with SPS to manage potassium levels.
- Both brand-name and generic SPS demonstrated comparable efficacy in potassium removal from infant formula.
Background:
In pediatric patients at risk of hyperkalemia there are limited treatment or preventive alternatives for this electrolyte imbalance. Oral or rectal sodium polystyrene sulfonate (SPS) has several potential adverse effects, and dietary potassium restriction may compromise nutrition. Pretreatment of infant formula with SPS has been previously studied with promising efficacy. The optimal dosing and contact time has not been fully elucidated for this practice, nor have brand and generic products been compared.
Objective:
The present study aimed to evaluate the effectiveness of varying amounts of brand and generic SPS for the removal of potassium from formula after 1 and 24 hours.
Methods:
SPS was added to infant formula in four different amounts measured in milliliters to reflect how a parent or caregiver would measure this product at home. After 1 and 24 hours samples were withdrawn and potassium and sodium levels were measured.
Results:
Potassium decreased in all samples, with the greatest reduction after the addition of 10 mL of SPS. Sodium levels increased in all pretreated samples to a greater extent than the potassium reduction. Contact time of either 1 or 24 hours did not impact the amount of potassium removed or the increase in sodium concentration. There were also no differences found between generic and brand SPS products.
Conclusion:
The effectiveness of SPS for formula pretreatment appears to have a plateau effect beyond the addition of 20 mL (16.47 g of brand name product, 19.5 g of generic product). This study demonstrates an effective protocol for pretreatment of formula.
