---
kind: "section"
citation: "21 C.F.R. § 358.303"
title: "21"
number: "358.303"
heading: "Definitions."
url: "https://uscodex.org/cfr/21/358.303"
---

# §358.303. Definitions.


As used in this subpart:

- (a) **Ingrown toenail relief drug product.** A drug product applied to an ingrown toenail that relieves pain or discomfort either by softening the nail or by hardening the nail bed.
- (b) **Retainer ring.** A die cut polyethylene foam pad coated on one side with medical grade acrylic pressure-sensitive adhesive. The retainer ring has slots, center-cut completely through the foam with the cut of sufficient size to allow for localization of an active ingredient in a gel vehicle to a specific target area. The retainer ring is used with adhesive bandage strips to place over the retainer ring to hold it in place.

## Notes

### Source

Source: 68 FR 24348, May 7, 2003, unless otherwise noted.

### Authority

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

### Source

Source: 55 FR 33255, Aug. 14, 1990, unless otherwise noted.