Comprehensive medication guide to Calcium Acetate including estimated pricing, availability information, side effects, and how to find it in stock at your local pharmacy.
Estimated Insurance Pricing
$0–$20 copay for generic on most Medicare Part D and commercial plans (typically Tier 1–2); patients qualifying for Medicare Extra Help (LIS) may pay as little as $0–$4 per fill.
Estimated Cash Pricing
$26–$38 with GoodRx or SingleCare coupons for 180 capsules (667 mg) at major pharmacy chains; retail price approximately $134 without a coupon for a 30-day supply.
Medfinder Findability Score
82/100
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Calcium acetate is an FDA-approved prescription medication used to treat hyperphosphatemia — high levels of phosphate in the blood — in patients with end-stage renal disease (ESRD) who are on dialysis. The FDA first approved it in December 1990. It is sold under the brand names PhosLo, Phoslyra, Eliphos, and Calphron, as well as as a widely available generic.
Calcium acetate belongs to the drug class known as phosphate binders (Minerals and electrolytes). It is available as a 667 mg capsule, a 667 mg tablet, and as an oral solution (Phoslyra, 667 mg per 5 mL). It is not a controlled substance and is taken with every meal to bind dietary phosphate before it is absorbed.
Dialysis patients typically take 3–4 tablets or capsules per meal (9–12 per day at maintenance dose), making it one of the highest-volume oral medications in the dialysis patient population. The standard starting dose is 2 tablets or capsules (1334 mg) per meal, titrated up every 2–3 weeks based on serum phosphate levels.
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Calcium acetate is a calcium salt that is highly soluble in the acidic environment of the stomach. When taken with a meal, calcium acetate dissolves and releases calcium ions into the gastrointestinal tract. These calcium ions bind to dietary phosphate from the food, forming insoluble calcium phosphate — a compound the body cannot absorb.
The insoluble calcium phosphate passes through the digestive tract and is excreted in the stool, preventing the phosphate from entering the bloodstream. This is why calcium acetate must be taken with every meal — without concurrent food intake, there is no dietary phosphate present in the gut for it to bind.
Research has demonstrated that calcium acetate is approximately twice as efficient as calcium carbonate at binding phosphate on an equimolar basis, meaning effective phosphate control can be achieved with lower total calcium intake — reducing the risk of hypercalcemia while still meeting phosphate-binding goals.
667 mg — capsule
Most common form; brand names include PhosLo Gelcap
667 mg — tablet
Available as generic and under the Eliphos brand name
667 mg/5 mL — oral solution
Liquid form sold as Phoslyra; prescribed for patients unable to swallow capsules or tablets
As of 2026, calcium acetate is not on the FDA's active drug shortage list and is manufactured by multiple generic pharmaceutical companies. Overall national supply is adequate. However, patients still regularly encounter availability gaps at individual pharmacies — particularly with brand-name versions (PhosLo, Eliphos) and the liquid formulation (Phoslyra).
Availability gaps occur primarily because dialysis patients require very high monthly volumes (200–400 units/month), not all pharmacies maintain adequate stock, and smaller or rural pharmacies may not carry it at all. The oral solution (Phoslyra) is rarely stocked at standard retail pharmacies and often requires special ordering.
If you are having trouble locating calcium acetate, medfinder is a paid service that calls pharmacies near you to check which ones have your medication in stock. You provide your medication and location — medfinder contacts pharmacies and texts you the results.
Calcium acetate is not a controlled substance and has no DEA scheduling restrictions. Any licensed prescriber can write a prescription for it without special registration. However, because it is indicated specifically for dialysis patients with ESRD, the prescribing is primarily concentrated among nephrology specialists and dialysis care teams.
Typical prescribers include:
Nephrologists (primary prescribers for ESRD and dialysis patients)
Internists and primary care physicians (PCPs) managing CKD patients
Nurse practitioners (NPs) and physician assistants (PAs) in nephrology practices
Dialysis center medical directors and hospitalists managing ESRD patients
Telehealth availability is good — because calcium acetate is not a controlled substance, nephrology practices and internal medicine providers can prescribe it via telehealth without any additional prescribing restrictions. Established dialysis patients can often obtain prescription renewals through telehealth appointments.
No. Calcium acetate is not a controlled substance and is not assigned to any DEA schedule. It has no abuse potential and no special prescribing restrictions. It requires a standard prescription and can be prescribed by any licensed physician, nurse practitioner, or physician assistant without special DEA registration.
Because calcium acetate is not a controlled substance, it can be prescribed via telehealth without any additional restrictions. Prescriptions can be sent electronically to any pharmacy, and 90-day supplies are permitted through mail-order programs. There are no refill quantity limits imposed by DEA regulations.
The most important safety concern with calcium acetate is hypercalcemia (high blood calcium), which can be asymptomatic or cause weakness, confusion, bone pain, and serious heart rhythm problems. Regular monitoring of serum calcium is required.
Common side effects:
Nausea
Vomiting
Constipation
Upset stomach / general GI discomfort
Serious side effects (seek medical attention):
Hypercalcemia: weakness, confusion, fatigue, headache, bone pain, loss of appetite, worsening constipation
Dangerous heart rhythm problems (especially if taking digoxin)
Severe allergic reaction: hives, swelling of face/lips/tongue/throat, difficulty breathing
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Sevelamer carbonate (Renvela)
Non-calcium phosphate binder; preferred when hypercalcemia is a concern; available as generic; higher pill burden
Sevelamer hydrochloride (Renagel)
Non-calcium polymer binder; similar to sevelamer carbonate; may reduce bicarbonate levels
Lanthanum carbonate (Fosrenol)
Non-calcium chewable tablet; lower pill burden than sevelamer; FDA-approved since 2004
Ferric citrate (Auryxia)
Iron-based binder; dual benefit of lowering phosphate and treating iron deficiency anemia in CKD
Sucroferric oxyhydroxide (Velphoro)
Iron-based chewable tablet; fewer tablets per day than sevelamer; calcium-free
Prefer Calcium Acetate? We can find it.
Digoxin (Lanoxin)
majorHypercalcemia from calcium acetate increases digoxin sensitivity; monitor digoxin levels regularly
Fluoroquinolone antibiotics (ciprofloxacin, levofloxacin, moxifloxacin)
moderateCalcium forms insoluble complexes with fluoroquinolones; separate by at least 2 hours before or 6 hours after
Tetracycline antibiotics (doxycycline, minocycline, tetracycline)
majorCalcium significantly reduces tetracycline absorption; take antibiotics at least 1 hour before calcium acetate
Levothyroxine (Synthroid, Tirosint)
moderateCalcium impairs levothyroxine absorption; separate by at least 4 hours before or after
Eltrombopag (Promacta)
majorCalcium significantly reduces eltrombopag absorption; separate by at least 4 hours
Dolutegravir (Tivicay)
moderateCalcium reduces dolutegravir absorption; take dolutegravir 2-4 hours before or 6 hours after
Calcium supplements / antacids (Tums, Caltrate)
moderateConcurrent use increases hypercalcemia risk; avoid unless directed by nephrologist
Vitamin D supplements
moderateVitamin D increases calcium absorption; may cause hypercalcemia when combined with calcium acetate
Calcium acetate is a cornerstone medication for dialysis patients managing hyperphosphatemia. It is an effective, proven phosphate binder that has been FDA-approved since 1990, widely available as a generic, and significantly more cost-effective than most newer phosphate binder alternatives. For most dialysis patients without hypercalcemia, it remains a first-line choice.
The key challenges with calcium acetate are not effectiveness — it is well established in that regard — but rather pharmacy access and cost management. Patients need large monthly supplies, and not all pharmacies stock it reliably. Switching to generic, using mail-order pharmacy, and exploring patient assistance programs are the most impactful strategies for maintaining consistent, affordable access.
If you are struggling to find calcium acetate at a pharmacy near you, medfinder is a paid service that contacts pharmacies on your behalf to find which ones have it in stock, then texts you the results — saving you hours of searching on your own.
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Real-time availability
Medfinder is actively checking pharmacy inventory for Calcium Acetate. We don't publish a number until we have enough verified pharmacy checks to be accurate — start a search and our team confirms current availability near you, usually within 24 hours.
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