---
kind: "section"
citation: "21 C.F.R. § 331.10"
title: "21"
number: "331.10"
heading: "Antacid active ingredients."
url: "https://uscodex.org/cfr/21/331.10"
---

# §331.10. Antacid active ingredients.

- (a) The active antacid ingredients of the product consist of one or more of the ingredients permitted in [§ 331.11](/cfr/21/331.11.md) within any maximum daily dosage limit established, each ingredient is included at a level that contributes at least 25 percent of the total acid neutralizing capacity of the product, and the finished product contains at least 5 meq of acid neutralizing capacity as measured by the procedure provided in the United States Pharmacopeia 23/National Formulary 18. The method established in [§ 331.20](/cfr/21/331.20.md) shall be used to determine the percent contribution of each antacid active ingredient.
- (b) This section does not apply to an antacid ingredient specifically added as a corrective to prevent a laxative or constipating effect.

## Notes

### Amendments

[39 FR 19874, June 4, 1974, as amended at 61 FR 4822, Feb. 8, 1996]

### Authority

Authority: 21 U.S.C. 321, 351, 352, 353, 355, 360, 371.

### Source

Source: 39 FR 19874, June 4, 1974, unless otherwise noted.

### Amendments

[39 FR 19874, June 4, 1974, as amended at 61 FR 4822, Feb. 8, 1996]