The short version
20 companies supply this market — deep enough that no single failure threatens the supply.
The numbers behind every sentence are on this page below — and the Watch button emails you when any of them move.
Antacid Tablets · CALCIUM CARBONATE 500 mg/1 · Tablet, Chewable · Oral · Chain Drug Consortium
NDC 68016-0668-00 · 150 TABLET, CHEWABLE in 1 BOTTLE, PLASTIC · OTC MONOGRAPH DRUG · View full market →
20 companies supply this market — deep enough that no single failure threatens the supply.
The numbers behind every sentence are on this page below — and the Watch button emails you when any of them move.
Medicare Part D does not cover over-the-counter drugs — by law it pays only for products requiring a prescription.
How Part D pricing works →No NADAC pricing on file for this NDC — NADAC covers drugs dispensed by retail community pharmacies.
Not scored — fragility is computed for NADAC-priced NDCs.
sole-source market · price up 1% YoY
For scale: the typical drug’s chance is about 0.1% — this one is in ordinary territory.
Backtested statistical model over the whole market, not this package alone. Model details →
No FDA shortage reports for this drug or its presentations.
No enforcement reports list this package NDC.
| Labeler | Strength | First seen | Last seen |
|---|---|---|---|
| Chain Drug Consortium | CALCIUM CARBONATE 500 mg/1 | Jul 15, 2026 | Sep 3, 2026 |
| Cvs Pharmacy,inc. | CALCIUM CARBONATE 750 mg/1 | Jul 15, 2026 | Sep 3, 2026 |
| Safeway | CALCIUM CARBONATE 750 mg/1 | Jul 15, 2026 | Sep 3, 2026 |
| Wal-Mart Stores,Inc., | CALCIUM CARBONATE 750 mg/1 | Jul 15, 2026 | Sep 3, 2026 |
| Chain Drug Marketing Association | CALCIUM CARBONATE 500 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Cvs | CALCIUM CARBONATE 1000 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Cvs | CALCIUM CARBONATE 750 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Cvs Pharmacy | CALCIUM CARBONATE 750 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| CVS Pharmacy,Inc. | CALCIUM CARBONATE 1000 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| H-E-B | CALCIUM CARBONATE 750 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Lidl US LLC | CALCIUM CARBONATE 1000 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Major Pharmaceuticals | CALCIUM CARBONATE 500 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| NuCare Pharmaceuticals,Inc. | CALCIUM CARBONATE 500 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Rugby Laboratories | CALCIUM CARBONATE 500 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Rugby Laboratories | CALCIUM CARBONATE 750 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Rugby Laboratories, Inc. | CALCIUM CARBONATE 500 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Safeway | CALCIUM CARBONATE 1000 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Target corporation | CALCIUM CARBONATE 750 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| The Kroger Co., | CALCIUM CARBONATE 1000 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Wal-Mart Stores,Inc., | CALCIUM CARBONATE 1000 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Walgreen Co. | CALCIUM CARBONATE 500 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Whole Foods Market, Inc. | CALCIUM CARBONATE 1000 mg/1 | Jul 15, 2026 | Sep 2, 2026 |
| Target Corporation | CALCIUM CARBONATE 750 mg/1 | Jul 15, 2026 | Aug 31, 2026 |
| Chain Drug Consortium, LLC | CALCIUM CARBONATE 500 mg/1 | Jul 15, 2026 | Aug 28, 2026 |
Roster from daily NDC Directory diffs — first/last seen dates start July 2026.
DrugDashboards, "Premier Value Chewable Antacid Extra Strength Tropical Fruit — NDC 68016-0668-00," retrieved September 3, 2026, https://drugdashboards.com/drug/68016066800.
Free to cite with attribution — see how the data is put together.