Provider Briefing: Sodium Polystyrene Sulfonate Supply in 2026

Sodium Polystyrene Sulfonate (SPS) — marketed as Kayexalate and available generically — has been a workhorse medication for hyperkalemia management for nearly seven decades. However, ongoing supply disruptions, particularly for the oral and rectal suspension formulation, have created prescribing challenges across nephrology, emergency medicine, and primary care settings.

This briefing covers the current shortage landscape, its implications for clinical practice, alternative agents, and tools to help your patients access this medication.

Shortage Timeline

The supply challenges for Sodium Polystyrene Sulfonate are not new but have intensified over recent years:

• Pre-2020: Intermittent spot shortages of the suspension form, primarily distribution-related
• 2020-2023: Broader supply chain disruptions exacerbated availability. The suspension was listed on the ASHP drug shortage database.
• 2024: Hikma Pharmaceuticals formally exited the suspension market, removing a significant source of supply
• 2025-2026: The suspension remains in shortage. The powder formulation continues to be available from manufacturers including ECI Pharmaceuticals, Amneal, and Carolina Medical Products, though localized shortages occur.

The ASHP Drug Shortage Resource Center maintains current information on both the suspension and powder formulations — providers should check both listings, as they are tracked separately.

Prescribing Implications

The shortage has several practical implications for prescribers:

Formulation Considerations

If you have been prescribing the pre-mixed suspension (15 g/60 mL), consider transitioning patients to the powder formulation when clinically appropriate. The powder must be reconstituted by the patient or caregiver with water. Key counseling points:

• Do not mix with heated foods or liquids (reduces efficacy)
• Do not mix with potassium-rich beverages (orange juice, etc.)
• Administer other oral medications at least 3 hours before or after SPS
• Patients with gastroparesis may need a longer separation interval

Sorbitol Coadministration

A reminder: the FDA issued a safety warning in 2009 against the concomitant use of SPS with sorbitol due to reports of colonic necrosis, including fatal cases. Sorbitol-containing SPS products should be avoided. Ensure any generic product dispensed does not contain sorbitol.

Patient Monitoring

SPS is non-selective in its cation exchange. When initiating or continuing therapy, monitor:

• Serum potassium (target response within 2-24 hours)
• Serum magnesium and calcium (SPS can bind both)
• Sodium levels (each gram of SPS contains ~4.1 mEq sodium)
• GI symptoms — particularly in elderly patients or those with reduced bowel motility

Current Availability Picture

As of early 2026:

• Powder form: Available from multiple generic manufacturers. Typical supply is adequate nationally, though individual pharmacies may experience temporary stockouts.
• Suspension form: Limited availability. Hikma is not marketing. Other manufacturers may produce limited quantities. Check ASHP for current supplier status.
• Rectal formulation: Availability mirrors the suspension — limited. In institutional settings, the powder can be reconstituted for rectal administration per pharmacy protocols.

Cost and Access Considerations

Sodium Polystyrene Sulfonate remains one of the most affordable potassium-lowering agents available:

• Generic powder (454 g): $6-$50 retail; as low as $5.70 with discount coupons
• Brand Kayexalate: $47-$100
• Insurance: Generic SPS is typically Tier 1-2 with no prior authorization required

In contrast, the newer potassium binders carry significantly higher costs:

• Patiromer (Veltassa): $600-$900/month
• Sodium Zirconium Cyclosilicate (Lokelma): $500-$800/month

For patients facing cost barriers, no manufacturer savings programs exist specifically for SPS. However, discount cards (GoodRx, SingleCare) effectively reduce generic costs. Patient assistance through NeedyMeds or RxAssist may help uninsured patients. For a comprehensive patient resource, see our guide: How to Save Money on Sodium Polystyrene Sulfonate.

Alternative Agents

When SPS is unavailable or contraindicated, two FDA-approved alternatives warrant consideration:

Patiromer (Veltassa)

• Calcium-based cation-exchange polymer (approved 2015)
• Binds potassium primarily in the colon
• No risk of intestinal necrosis (a significant advantage over SPS)
• Onset: 4-7 hours for initial effect
• Must separate from other oral medications by at least 3 hours
• May require prior authorization; manufacturer copay card available for commercially insured patients

Sodium Zirconium Cyclosilicate (Lokelma)

• Inorganic crystalline compound (approved 2018)
• Highly selective potassium trap with faster onset (within 1 hour)
• Contains sodium (~400 mg per 5 g dose) — consider in heart failure patients
• Can be used for both acute and maintenance therapy
• May require prior authorization; AstraZeneca offers patient support programs

For patients who cannot access any potassium binder, loop diuretics (e.g., Furosemide) can provide adjunctive potassium lowering in patients with adequate renal function. Dietary potassium restriction should be reinforced in all hyperkalemic patients.

For a patient-facing comparison, refer patients to: Alternatives to Sodium Polystyrene Sulfonate.

Tools and Resources for Providers

Several tools can help you and your patients navigate the shortage:

• Medfinder for Providers: Search real-time pharmacy inventory to identify locations with SPS in stock. Share with patients to reduce call burden on your office.
• ASHP Drug Shortage Database: Monitor current shortage status and manufacturer updates
• Pharmacy consultation: Your institution's pharmacy team can help identify alternative suppliers, especially for inpatient use

Documentation Tips

When switching patients to alternative potassium binders due to shortage:

• Document SPS unavailability in the chart to support prior authorization for alternatives
• Note the formulation switch (suspension → powder) and patient education provided
• Update medication reconciliation at each encounter

Looking Ahead

The SPS suspension shortage is unlikely to resolve quickly given the limited number of manufacturers and low profit margins that discourage market entry. Providers should:

• Preferentially prescribe the powder formulation going forward, as it has more stable supply
• Familiarize themselves with Patiromer and Lokelma dosing and insurance navigation
• Ensure patients have a plan before they run out — proactive prescription management is critical
• Use Medfinder for Providers to streamline pharmacy search for patients

Final Thoughts

The Sodium Polystyrene Sulfonate shortage reflects a broader trend in generic drug supply fragility. While the powder form remains a reliable option, prescribers should be prepared to pivot to alternative agents when necessary. The key is proactive management: don't wait until your patient's last dose to address availability.

For provider-specific tools and resources, visit medfinder.com/providers. For additional guidance on helping patients navigate cost and access barriers, see our provider guide: How to Help Your Patients Find Sodium Polystyrene Sulfonate in Stock.