---
kind: "unit"
title: "21"
title_heading: "Food and Drugs"
key: "chI/subchD/part331"
level: "part"
label: "Part 331"
heading: "Antacid Products for Over-The-Counter (otc) Human Use"
release: "ecfr-current"
date: "2026-08-27"
url: "https://uscodex.org/cfr/21/chI-subchD-part331"
sections_count: 8
---

# Part 331 — Antacid Products for Over-The-Counter (otc) Human Use

Title 21 C.F.R. — Food and Drugs › Chapter I — Food and Drug Administration, Department of Health and Human Services › Subchapter D — Drugs for Human Use

## Contents

- [Subpart A — General Provisions](/cfr/21/chI-subchD-part331-subpartA.md)
- [Subpart B — Active Ingredients](/cfr/21/chI-subchD-part331-subpartB.md)
- [Subpart C — Testing Procedures](/cfr/21/chI-subchD-part331-subpartC.md)
- [Subpart D — Labeling](/cfr/21/chI-subchD-part331-subpartD.md)