Calcium Acetate
Calcium acetate is a phosphate binder used to lower high phosphorus levels in people with end stage renal disease (kidney failure) who are on dialysis.
🧬 Where this information comes from Click to expand
The clinical label records used on this page are FDA-filed Structured Product Labeling (SPL) retrieved through openFDA. We identified 25 clinical label sets within the page’s selected clinical scope after exact ingredient or ingredient-combination matching and applicable route/form matching. Forms, routes, brands, labelers, strengths, and NDC product-record counts are built separately from matching FDA National Drug Code Directory records. The linked DailyMed document is a representative official source for verification, not the page’s only clinical source. View the linked label on DailyMed →
Calcium acetate is a phosphate binder for people with end stage renal disease (kidney failure). It works in the gut, grabbing phosphate from food so it leaves in your stool instead of reaching your blood. One of the oldest and most familiar binders, it has been on the market since about 1982 and is available generically. Most people tolerate it reasonably well, and nausea, sometimes with vomiting, is what people notice most. The one thing to watch is high blood calcium (hypercalcemia), so keep every blood test, call your care team for constipation or loss of appetite that does not settle, and get help right away for confusion or extreme drowsiness.
Clinical pearls
- Take it with each meal, because it only works when it meets the phosphate from that food in your gut.
- Space other oral medicines 1 hour before or 3 hours after it, especially tetracycline or fluoroquinolone antibiotics like ciprofloxacin.
- Skip calcium supplements and calcium-based antacids such as Tums, since the extra calcium can push your level too high.
- If you take digoxin, make sure your care team knows, because high calcium can make digoxin toxicity worse.
Patient information guide A plain-language walkthrough of Calcium Acetate, written from its FDA label.
What Calcium Acetate is used for
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Calcium acetate is a phosphate binder used in kidney failure.
- Lowers serum phosphorus (blood phosphorus) in people with end stage renal disease (ESRD).
- Calcium Acetate capsules and Calcium Acetate tablets are each labeled for this use.
How Calcium Acetate works
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When your kidneys fail, phosphorus builds up in your blood. Too much phosphorus can cause calcium to be deposited in tissues where it does not belong. It also plays a role in secondary hyperparathyroidism (overactive parathyroid glands).
Taken with meals, calcium acetate binds phosphate from your food in the gut. This forms an insoluble calcium phosphate that leaves the body in your stool, lowering blood phosphorus.
Calcium Acetate dosage
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Calcium acetate is taken by mouth with each meal. Adult dialysis patients usually start with 2 capsules or tablets per meal, and most end up needing 3 to 4 per meal.
- Your prescriber raises the dose gradually, about every 2 to 3 weeks, until phosphorus is in the target range.
- The dose is increased only as long as high blood calcium does not develop.
- Follow your prescriber and the label for your exact dose.
Dosing details from the FDA-approved label
From the Calcium Acetate prescribing information (“Dosage and Administration”). Doses are set by your prescriber for your product, condition, kidney function and age — never change a dose on your own.
- Adult dialysis patient (capsules)
- Recommended initial dose is 2 capsules with each meal
- Increase the dose gradually to lower serum phosphorus levels to the target range, as long as hypercalcemia does not develop
- Titrate the dose every 2 to 3 weeks until acceptable serum phosphorus level is reached
- Most patients require 3 to 4 capsules with each meal
- Adult dialysis patient (tablets)
- Recommended initial dose is 2 tablets with each meal
- Increase the dose gradually to lower serum phosphorus levels to the target range, as long as hypercalcemia does not develop
- Titrate the dose every 2 to 3 weeks until acceptable serum phosphorus level is reached
- Most patients require 3 to 4 tablets with each meal
Read the label’s full dosing text
2 DOSAGE AND ADMINISTRATION The recommended initial dose of calcium acetate capsules for the adult dialysis patient is 2 capsules with each meal. Increase the dose gradually to lower serum phosphorus levels to the target range, as long as hypercalcemia does not develop. Most patients require 3 to 4 capsules with each meal. Starting dose is 2 capsules with each meal. ( 2 ) Titrate the dose every 2 to 3 weeks until acceptable serum phosphorus level is reached. Most patients require 3 to 4 capsules with each meal. ( 2 )
Read the full Dosage and Administration section on DailyMed →
Calcium Acetate side effects
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Calcium acetate is generally well tolerated. The most common side effects are:
Common side effects
- High blood calcium (hypercalcemia)
- Nausea
- Vomiting
- Dizziness
- Swelling (edema)
- Weakness
- Itching (isolated cases)
When to get medical help
- Call your doctor if you have constipation, loss of appetite, nausea or vomiting that does not settle, as these can be signs of mild high blood calcium.
- Get medical help right away if you have confusion, delirium, extreme drowsiness or loss of consciousness, which can signal severe high blood calcium.
- Call your doctor if you develop itching or other signs of an allergic reaction.
- Taking more than prescribed can cause high blood calcium that may need emergency care.
Contact your doctor if you have confusion, severe drowsiness, or ongoing nausea, vomiting or constipation. These can signal high blood calcium.
Calcium Acetate warnings and precautions
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- Hypercalcemia is the main risk. Mild cases may cause constipation, poor appetite, nausea and vomiting. Severe cases (above 12 mg/dL) can cause confusion, delirium, stupor and coma.
- Calcium levels are checked twice weekly early in treatment while the dose is adjusted.
- If calcium runs high, the dose is reduced or stopped. Severe cases may need hemodialysis.
- Long-term high calcium may lead to vascular and soft-tissue calcification (calcium deposits).
- High calcium may make digitalis toxicity worse.
Calcium Acetate interactions
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Calcium can bind to other medicines and reduce how well they are absorbed.
- Tetracyclines and fluoroquinolones: absorption may drop. Ciprofloxacin absorption fell by about 50% in one study.
- Other oral medicines: take them 1 hour before or 3 hours after calcium acetate if reduced absorption would matter.
- Drugs with a narrow therapeutic range: your doctor may monitor blood levels.
- Calcium supplements and calcium-based antacids: avoid them, as they can push calcium too high.
- Digitalis: high calcium can worsen its toxicity.
- Vitamin D: may need to be lowered or stopped if calcium is high.
Interactions listed in the FDA-approved label
From the Calcium Acetate prescribing information (“Drug Interactions”): what the manufacturer studied or reported to the FDA.
- Tetracyclines: Calcium acetate capsules may decrease the bioavailability of tetracyclines because calcium can bind to drugs with anionic functions. Administer the drug one hour before or three hours after calcium acetate capsules, or consider monitoring blood levels of the drug.
- Fluoroquinolones: Calcium acetate capsules may decrease the bioavailability of fluoroquinolones because calcium can bind to drugs with anionic functions. Administer the drug one hour before or three hours after calcium acetate capsules, or consider monitoring blood levels of the drug.
- Ciprofloxacin: In a study of 15 healthy subjects, a co-administered single dose of 4 calcium acetate tablets approximately 2.7 g decreased the bioavailability of ciprofloxacin by approximately 50%.
- Oral medications where reduced bioavailability would have a clinically significant effect on safety or efficacy: There are no empirical data on avoiding drug interactions between calcium acetate and most concomitant drugs. Administer the drug one hour before or three hours after calcium acetate capsules or calcium acetate. Monitor blood levels of concomitant drugs that have a narrow therapeutic range.
- Anti-arrhythmic and anti-seizure medications: Patients taking anti-arrhythmic medications for the control of arrhythmias and anti-seizure medications for the control of seizure disorders were excluded from the clinical trials with all forms of calcium acetate.
Read the label’s full interactions text
7. DRUG INTERACTIONS The drug interaction of calcium acetate capsules is characterized by the potential of calcium to bind to drugs with anionic functions (e.g., carboxyl and hydroxyl groups). Calcium acetate capsules may decrease the bioavailability of tetracyclines or fluoroquinolones via this mechanism. There are no empirical data on avoiding drug interactions between calcium acetate or calcium acetate capsules and most concomitant drugs. When administering an oral medication with calcium acetate capsules where a reduction in the bioavailability of that medication would have a clinically significant effect on its safety or efficacy, administer the drug one hour before or three hours after calcium acetate capsules or calcium acetate. Monitor blood levels of the concomitant drugs that have a narrow therapeutic range. Patients taking anti-arrhythmic medications for the control of arrhythmias and anti-seizure medications for the control of seizure disorders were excluded from the clinical trials with all forms of calcium acetate. • Calcium acetate capsules may decrease the bioavailability of tetracyclines or fluoroquinolones. ( 7 ) • When clinically significant drug interactions are expected, administer the drug at least one hour before or at least three hours after calcium acetate capsules, or consider monitorinG blood levels of the drug. ( 7 ) 7.1 Ciprofloxacin In a study of 15 healthy subjects, a co-administered single dose of 4 calcium acetate tablets approximately 2.7 g decreased the bioavailability of ciprofloxacin by approximately 50%.
Not a complete list. The label covers the interactions the manufacturer studied or reported, and our own interaction database does not cover every medicine either. Bring your full medication list, including vitamins and herbal products, to your pharmacist.
Before taking Calcium Acetate
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- Do not use if you have hypercalcemia.
- Tell your doctor about all calcium products, antacids, vitamin D and heart medicines you take.
- Pregnancy: high calcium may raise risks such as stillbirth and preterm delivery. Calcium levels should be monitored.
- Breastfeeding: it passes into milk, but is not expected to harm an infant if your calcium is monitored.
- Children: safety and effectiveness have not been established.
- Older adults: dosing usually starts at the low end because of a higher chance of reduced liver, kidney or heart function.
Calcium Acetate overdose
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Taking more than the proper daily dose may cause hypercalcemia. An overdose may lead to progressively rising calcium that can require emergency measures. Get medical help right away if you take too much.
What Calcium Acetate does in the body
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Calcium acetate lowers blood phosphorus by binding dietary phosphate in the gut. Some of the calcium is absorbed into the body, up to about 40% when taken fasting and up to about 30% when taken with food. This is why blood calcium needs monitoring.
How to store Calcium Acetate
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Store at 20°-25°C (68°-77°F); excursions permitted to 15° to 30°C (59° to 86°F) .
Written from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →
Calcium Acetate: pharmacist answers to common questions
Quick, plain-English answers to the questions patients ask most about Calcium Acetate — the kind of thing our pharmacy team would talk through with you at the counter.
What is calcium acetate for?
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When should I take it?
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What side effects should I expect?
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Can I take calcium supplements or antacids with it?
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Does it affect my other medicines?
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Is it safe during pregnancy or breastfeeding?
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Is Calcium Acetate available over the counter?
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When was Calcium Acetate first available?
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Who makes Calcium Acetate?
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Answers drafted from the FDA-approved label with AI and reviewed by our pharmacy team. How we use AI →
More about Calcium Acetate on HelloPharmacist
Calcium Acetate forms and strengths (how it comes)
Calcium Acetate is available in 2 forms. Different forms and brands can have different approved uses, doses, schedules, and directions. Follow the instructions for your exact product, and do not switch forms without guidance from your prescriber or pharmacist.
Capsule
How this form is used
- Calcium Acetate capsules are used to reduce serum phosphorus in people with end stage renal disease.
- Calcium Acetate capsules are taken by mouth with each meal.
- Calcium Acetate capsules are adjusted every 2 to 3 weeks until phosphorus reaches an acceptable level.
Tablet
How this form is used
- Calcium Acetate tablets are used to reduce serum phosphorus in people with end stage renal disease.
- Calcium Acetate tablets are taken by mouth with each meal.
- Calcium Acetate tablets are adjusted every 2 to 3 weeks until phosphorus reaches an acceptable level.
Calcium Acetate on the U.S. market: products, makers and brands
How Calcium Acetate appears in the FDA’s National Drug Code Directory — including its dosage forms, strengths, brand names, manufacturers, and FDA-listed product records. These are directory records, not sales or prescription volume.
19 companies list 22 Calcium Acetate product records with the FDA, mostly as capsule, tablet; the earliest marketing or approval year on record is 1982. Brand names on the directory include Phoslo, Phoslyra, Calphron; the rest are generics.
FDA-listed product records by dose form (tablet variants merged) — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
Also listed with the FDA, not a patient dose form: Powder (5) — bulk drug substance sold to compounders/manufacturers and multi-item kits. These aren’t counted in the dose-form total above.
Share of FDA-listed product records by manufacturer — FDA National Drug Code Directory. Record counts are not sales or prescription volume.
How widely Calcium Acetate is used (Medicaid data)
A general measure of how commonly Calcium Acetate is prescribed, based on Medicaid — one of the largest public drug programs. The figure below is prescriptions filled in Q1–Q4 2025, summed across every form and brand of the drug.
Think of this as a proxy for how widely Calcium Acetate is used, drawn from freely available public data. Medicaid is just one program — these numbers don’t include Medicare, other government coverage, or commercial and cash-pay prescriptions, so real-world use is higher than what’s shown here.
How commonly is Calcium Acetate prescribed? Of the 1,601 medications we measure, Calcium Acetate ranks #543 by Medicaid prescriptions — more than 66% of them.
Utilization by Calcium Acetate product
Pick a product to see its own Medicaid numbers. Each chip is one clinical product — a specific strength & dosage form as defined by RxNorm — with brand-name and generic versions combined.
calcium acetate 667 MG Oral Capsule Most dispensed
Summed across the 11 of 52 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 359296
calcium acetate 667 MG Oral Tablet
Summed across the 2 of 6 listed NDC products with Medicaid activity — every brand and generic of this exact strength & form. RxNorm 197433
Shares are of the Medicaid prescriptions shown here. Product grouping follows RxNorm (the National Library of Medicine’s drug terminology), so “one product” means one strength & dosage form regardless of manufacturer. Dollar figures are gross Medicaid reimbursement before mandatory rebates — rebates (often large, especially for brand-name drugs) are confidential, so actual net cost to Medicaid is lower than shown.
Source: Medicaid State Drug Utilization Data (CMS), aggregated by generic ingredient — summed across every NDC (all brands, strengths, salt forms and dosage forms) of Calcium Acetate, and across all states and both fee-for-service and managed-care claims. A general popularity signal; it excludes Medicare, commercial insurance and cash prescriptions, so it is not total U.S. use. Based on the 13 of 58 listed Calcium Acetate NDCs with Medicaid activity.
Compare Calcium Acetate products
A representative set of FDA-listed product records for Calcium Acetate — across manufacturers, strengths, and dosage forms, grouped by form with each product’s manufacturer and how the FDA approved it. The same medicine may be made and packaged by different companies, so a single drug can have many directory entries. (It’s also why a refill can look different — a new shape, color, or box — even though it contains the same medication.)
| Strength | Route | Manufacturer / Labeler | Category ⓘ | Details |
|---|---|---|---|---|
| 💊Capsule | ||||
| 667 mg | Oral | American Health Packaging × 2 listings | ANDA | View NDC → |
| 667 mg | Oral | Amneal Pharmaceuticals of New York LLC | ANDA | View NDC → |
| 667 mg | Oral | AvKARE | ANDA | View NDC → |
| 667 mg | Oral | AvPAK | ANDA | View NDC → |
| 667 mg | Oral | Cardinal Health 107, LLC | ANDA | View NDC → |
| 667 mg | Oral | Chartwell RX, LLC. | ANDA | View NDC → |
| 667 mg | Oral | Cipla USA Inc., | ANDA | View NDC → |
| 667 mg | Oral | Exelan Pharmaceuticals, Inc. | ANDA | View NDC → |
| 667 mg | Oral | Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc. | ANDA | View NDC → |
| 667 mg | Oral | Hikma Pharmaceuticals USA Inc. | ANDA | View NDC → |
| 667 mg | Oral | Major Pharmaceuticals | ANDA | View NDC → |
| 667 mg | Oral | NCS HealthCare of KY, LLC dba Vangard Labs | ANDA | View NDC → |
| 667 mg | Oral | Nivagen Pharmaceuticals, Inc. | ANDA | View NDC → |
| 667 mg | Oral | PD-Rx Pharmaceuticals, Inc. | ANDA | View NDC → |
| 667 mg | Oral | Proficient Rx LP | ANDA | View NDC → |
| 667 mg | Oral | Remedyrepack Inc. | ANDA | View NDC → |
| 667 mg | Oral | Rising Pharma Holdings, Inc. | ANDA | View NDC → |
| 667 mg | Oral | Square Pharmaceuticals Limited | ANDA | View NDC → |
| 667 mg | Oral | Westminster Pharmaceuticals, LLC | ANDA | View NDC → |
| 💊Tablet | ||||
| 667 mg | Oral | Chartwell RX LLC | ANDA | View NDC → |
| 667 mg | Oral | Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc. | ANDA | View NDC → |
Showing 22 of 22 products — FDA National Drug Code Directory. See every product, package size and price: browse all 22 Calcium Acetate NDCs →
Calcium Acetate side effects reported to the FDA (FAERS)
After a medicine reaches the market, patients, doctors and drugmakers can send the FDA reports of problems they think may be linked to it. Here’s what’s been reported for Calcium Acetate — a signal of what to watch for, not proof the drug caused it.
Source: openFDA, from the FDA Adverse Event Reporting System (FAERS). These are voluntary reports — they don’t prove the drug caused the effect, and counts reflect how often something was reported, not how often it actually happens. Reports also often name the very problem the medicine is taken for — a common reason to file one is that the drug didn’t help — so for a pain reliever you may see “pain” high on the list; that points to why the report was filed, not to the drug causing the symptom. This counts every report that lists Calcium Acetate in any role, so the total runs higher than the FDA’s official dashboard, which counts only cases where the drug is the suspect. For the authoritative figures, see the FDA FAERS Public Dashboard. Always talk to your pharmacist or doctor.
Calcium Acetate FDA approval history
How Calcium Acetate went from FDA review to the pharmacy shelf — the key milestones in its regulatory journey.
Source: Drugs@FDA.
Calcium Acetate recall history
A recall is when a specific batch of a medicine is pulled from the market — usually a manufacturing issue, not a problem with the drug itself. Class I is most serious, Class III least.
The FDA’s enforcement reports list no Calcium Acetate recalls since July 2021.
✅No Calcium Acetate recalls on record since July 2021Source: FDA enforcement (recall) reports, via openFDA; our copy was last updated Sep 24, 2026.
RxNorm Concept Web — From Ingredient to Every Form and Strength
This page starts with one ingredient concept (IN). The branches below show its dose-form concepts (SCDF), then the available clinical drug and strength concepts (SCD). Combination products remain separate concepts with their own pages.
RxCUI 214342 3 dose forms · 7 strengths
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Dose form (SCDF) Oral Capsule RxCUI 375787In current FDA listings -
Dose form (SCDF) Oral Solution RxCUI 1099803No current FDA listingClinical drug / strength (SCD) 133 MG/MLRxCUI 1099804 -
Dose form (SCDF) Oral Tablet RxCUI 371195In current FDA listingsClinical drug / strength (SCD) 500 MGRxCUI 245146667 MGRxCUI 197433668 MGRxCUI 4287031000 MGRxCUI 245133
Look up RxCUI 214342 in the RxCUI Atlas →
RxNorm is the U.S. National Library of Medicine’s normalized drug vocabulary. Its concept hierarchy can include forms that are not currently marketed; the status on each branch compares that concept with current FDA listings. RxCUIs identify vocabulary concepts, not individual packages or manufacturers.
Calcium Acetate supply and shortage status
Whether Calcium Acetate is in short supply in the U.S. right now, plus any shortage history the FDA has on record. A shortage usually reflects a manufacturing or demand issue — not a safety problem with the drug.
Source: openFDA, from the FDA Drug Shortages database.
💵 What Calcium Acetate costs pharmacies (NADAC benchmark)
The national average invoice price pharmacies pay for the drug itself, from CMS's NADAC survey (data as of Sep 30, 2026). This is a supply-cost benchmark — not a retail price and not what you'd pay at the counter.
| Form | Strength | Pharmacy acquisition benchmark | |
|---|---|---|---|
| Capsule · Oral | 667 mg | $0.170 per capsule | NDC details & price history |
| Tablet · Oral | 667 mg | $0.439 per tablet | NDC details & price history |
Source: CMS National Average Drug Acquisition Cost (NADAC), a survey of retail pharmacy invoice prices. Benchmarks shown are the range across package sizes of a representative product for each form and strength — other manufacturers' products may differ.
Calcium Acetate brand names
Calcium Acetate is sold under 3 brand names in the FDA directory — Phoslo, Phoslyra, Calphron. A brand and its generic contain the same active ingredient; the brand name belongs to one company's product.
Who makes Calcium Acetate: manufacturers and labelers
19 companies list Calcium Acetate products with the FDA. By number of product records, the largest are American Health Packaging, Chartwell RX LLC, Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc.. Labelers include manufacturers and repackagers; the product in your bottle depends on which one your pharmacy stocks.
Calcium Acetate drug class (RxNorm)
Calcium Acetate belongs to the Drugs for treatment of hyperkalemia and hyperphosphatemia class.
Classified by RxNorm RxClass — the U.S. National Library of Medicine's standardized drug-classification service (Established Pharmacologic Class from the FDA, the ATC drug family from the WHO, and mechanism of action). Reference only, not medical advice.
Sources for this Calcium Acetate page
Core label, product, RxNorm, safety, and utilization data on this page come from the sources identified below. AI-written, editorial, and licensed sections are labeled separately.
How this page is built
HelloPharmacist combines public FDA and NLM records and does not author the underlying clinical facts. The plain-language sections are written with AI from the FDA-approved label text and reviewed by our pharmacy team before publication. Rising Pharma Holdings, Inc. is the representative DailyMed label linked for verification and dates. This is general education, not medical advice: always talk to your doctor or pharmacist about your own medicines. How we build and review drug pages →