Estimate and compare the likely monthly and annual out-of-pocket cost range for the three main potassium-binder medications discussed in our Lokelma vs Kayexalate guide. This is a planning estimate only, built from typical U.S. retail price ranges — your actual cost depends entirely on your insurance plan, pharmacy, and dose.
About these numbers: the ranges are approximate U.S. cash and list-price ranges for a typical maintenance dose, checked in 2026. They are a planning estimate, not a quote. Your real cost depends on your dose, your insurance formulary, your pharmacy and any manufacturer savings program. See our medical disclaimer.
The three potassium binders at a glance
Potassium binders are medicines you swallow that trap potassium in the gut so it leaves the body in stool instead of being absorbed. They are used for hyperkalemia (high blood potassium), most often in people with chronic kidney disease or people who need medicines such as ACE inhibitors, ARBs or spironolactone that tend to raise potassium. There are three options in the U.S., and they differ a lot in price, speed and side effects.
| Feature | Lokelma | Veltassa | Sodium polystyrene sulfonate (Kayexalate, SPS) |
|---|---|---|---|
| Generic name | Sodium zirconium cyclosilicate | Patiromer | Sodium polystyrene sulfonate |
| FDA approval | 2018 | 2015 | 1958 |
| How fast it starts lowering potassium | About 1 hour | About 7 hours | Hours, and less predictable |
| Typical maintenance dose | 10 g once daily (range 5 g every other day to 15 g daily) | 8.4 g once daily, adjusted up to 25.2 g | 15 g one to four times daily |
| Main side effect concern | Swelling (edema) from its sodium content | Constipation, low magnesium | Rare but serious bowel injury (intestinal necrosis) |
| Spacing from other oral medicines | 2 hours for drugs whose absorption depends on stomach acid | 3 hours before or after | 3 hours before or after (6 hours if you have gastroparesis) |
| Approximate monthly cash price | $500 to $800 | $900 to $1,200 | $20 to $120 (generic powder) |
Why the price gap is so large
Sodium polystyrene sulfonate has been off patent for decades and is sold as an inexpensive generic powder, which is why it costs a fraction of the others. Lokelma and Veltassa are newer brand-only drugs with patent protection, so there is no generic competition yet. The newer drugs are not simply “the expensive version”: they were developed partly because of safety problems with SPS. The FDA added a warning to SPS labeling about intestinal necrosis, a rare but sometimes fatal bowel injury, and the newer binders have not shown that problem in their trials. Lokelma also works faster, which matters to some doctors when potassium needs to come down within hours.
How to bring the cost down
- Check your formulary tier. Many Medicare Part D and commercial plans cover at least one of the newer binders, often with prior authorization. Ask your prescriber’s office to submit it if it is needed.
- Manufacturer programs. AstraZeneca (Lokelma) and CSL Vifor (Veltassa) both run copay savings programs for commercially insured patients and patient-assistance programs for people who qualify by income. Medicare patients usually cannot use copay cards but may qualify for assistance programs or Extra Help.
- Discount cards. For cash-pay patients, pharmacy discount cards can make a large difference, especially for generic SPS.
- Ask whether a binder is needed long term. Sometimes high potassium can be managed by changing a diet, adjusting a diuretic or stopping a medicine that raises potassium. A binder is often used specifically so that a heart- or kidney-protective drug can be continued.
Cost is not the only thing to weigh
The cheapest option is not always the right one. Your prescriber will consider how high your potassium is, how fast it needs to fall, your kidney function, whether you retain fluid (Lokelma’s sodium content can matter in heart failure), whether you get constipated easily (Veltassa and SPS both cause it), and how many other oral medicines you take, because spacing doses can be hard with a long medication list. Our Lokelma vs Kayexalate guide covers these trade-offs in detail.
Related reading
- Lokelma vs Kayexalate: speed, safety and cost compared
- Hyperkalemia symptom checker
- Invokana vs Jardiance: kidney and heart data
- All Health Linear calculators and tools
Frequently asked questions
Is there a generic for Lokelma or Veltassa?
Not in the U.S. as of 2026. Both are still brand-only. The only generic potassium binder is sodium polystyrene sulfonate.
Does Medicare cover potassium binders?
Many Medicare Part D plans cover at least one newer binder, usually with prior authorization, and generic SPS is widely covered. Coverage and tier vary by plan, so check your plan’s formulary or ask your pharmacist.
Is Kayexalate still sold?
Generic sodium polystyrene sulfonate is widely available as a powder and suspension. Pharmacies and doctors often still call it “Kayexalate” even when the product dispensed is a generic.
Can I switch binders to save money?
Possibly, but only with your prescriber. The drugs work at different speeds, need different spacing from your other medicines and have different side effects, so your potassium should be rechecked after any switch.
Sources
- Lokelma (sodium zirconium cyclosilicate) prescribing information, DailyMed
- Veltassa (patiromer) prescribing information, DailyMed
- Sodium polystyrene sulfonate prescribing information, DailyMed
- Simon LV, et al. Hyperkalemia. StatPearls, NCBI Bookshelf
- Generic sodium polystyrene sulfonate cash prices, GoodRx (checked 2026)
About this article
Written by the Health Linear Editorial Team from primary sources such as FDA prescribing information, DailyMed, NIH and peer-reviewed studies, which are linked in the article. Last updated October 27, 2026.
Read our editorial process and medical disclaimer. Spotted an error? Tell us and we will correct it.