Table of Contents
- What is Calcium Polystyrene Sulfonate?
- Conditions Treated
- How It Works
- Administration and Dosage
- Effectiveness
- Side Effects and Considerations
- Comparisons with Other Treatments
- Ongoing Research
What is Calcium Polystyrene Sulfonate?
Calcium Polystyrene Sulfonate (CPS) is a medication used to treat high levels of potassium in the blood, a condition known as hyperkalemia. It belongs to a class of drugs called potassium binders or cation exchange resins. CPS is also known by other names, including:
- Sodium Polystyrene Sulfonate (SPS)
- Kayexalate
- Solystat
Conditions Treated
Calcium Polystyrene Sulfonate is primarily used to treat hyperkalemia in patients with:
- Chronic Kidney Disease (CKD): A long-term condition where the kidneys don’t function properly
- Acute Kidney Injury (AKI): A sudden episode of kidney failure or kidney damage
- Heart Failure: A condition where the heart can’t pump blood effectively
How It Works
Calcium Polystyrene Sulfonate works by binding to excess potassium in the intestines. When you take this medication, it travels through your digestive system and attracts potassium molecules. The medication then traps these potassium molecules and carries them out of your body through your stool. This process helps lower the amount of potassium in your blood[5].
Administration and Dosage
Calcium Polystyrene Sulfonate is typically administered orally as a powder mixed with water. The dosage can vary depending on the patient’s condition and potassium levels. Some common dosages seen in clinical trials include:
- 15g mixed with 60 mL of water, taken once daily on non-dialysis days
- 30g taken orally once daily for short periods (e.g., 7 days)
Effectiveness
Clinical trials have shown that Calcium Polystyrene Sulfonate can be effective in lowering potassium levels in patients with hyperkalemia. In one study, researchers found that CPS significantly reduced serum potassium levels compared to a placebo over a 48-hour period[5]. However, its effectiveness may vary from patient to patient, and it’s often used in combination with other treatments for managing hyperkalemia.
Side Effects and Considerations
While Calcium Polystyrene Sulfonate can be effective, it may cause some side effects. Common side effects reported in clinical trials include:
- Gastrointestinal issues (nausea, constipation, diarrhea)
- Electrolyte imbalances (changes in sodium, magnesium, or calcium levels)
- Changes in blood pressure
Comparisons with Other Treatments
In recent years, new potassium binders have been developed, leading to comparisons between Calcium Polystyrene Sulfonate and newer medications. Some of these newer treatments include:
- Sodium Zirconium Cyclosilicate (Lokelma)
- Patiromer (Veltassa)
Ongoing Research
Research on Calcium Polystyrene Sulfonate and other potassium binders is ongoing. Current studies are focusing on:
- Comparing the effectiveness of different potassium binders in emergency settings
- Evaluating patient preferences and palatability of various treatments
- Assessing long-term safety and efficacy in different patient populations



