---
kind: "section"
citation: "21 C.F.R. § 346.18"
title: "21"
number: "346.18"
heading: "Astringent active ingredients."
url: "https://uscodex.org/cfr/21/346.18"
---

# §346.18. Astringent active ingredients.


The active ingredient of the product consists of any of the following when used within the concentration range established for each ingredient:

- (a) Calamine, within a concentration range of 5 to 25 percent by weight per dosage unit (based on the zinc oxide content of calamine).
- (b) **Witch hazel, 10 to 50 percent.**
- (c) **Zinc oxide, within a concentration range of 5 to 25 percent by weight per dosage unit.**

## Notes

### Amendments

[55 FR 31779, Aug. 3, 1990, as amended at 59 FR 28767, June 3, 1994]

### Authority

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

### Source

Source: 55 FR 31779, Aug. 3, 1990, unless otherwise noted.

### Amendments

[55 FR 31779, Aug. 3, 1990, as amended at 59 FR 28767, June 3, 1994]