21 CFR § 346.3 - Definitions.
---
identifier: "/us/cfr/t21/s346.3"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 346.3 - Definitions."
title_number: 21
title_name: "Food and Drugs"
section_number: "346.3"
section_name: "Definitions."
chapter_name: "FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "D"
subchapter_name: "DRUGS FOR HUMAN USE"
part_number: "346"
part_name: "ANORECTAL DRUG PRODUCTS FOR OVER-THE-COUNTER HUMAN USE"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "21 U.S.C. 321, 351, 352, 353, 355, 360, 371."
regulatory_source: "55 FR 31779, Aug. 3, 1990, unless otherwise noted."
cfr_part: "346"
---
# 346.3 Definitions.
As used in this part:
(a) *Analgesic, anesthetic drug.* A topically (externally) applied drug that relieves pain by depressing cutaneous sensory receptors.
(b) *Anorectal drug.* A drug that is used to relieve symptoms caused by anorectal disorders in the anal canal, perianal area, and/or the lower rectal areas.
(c) *Antipruritic drug.* A topically (externally) applied drug that relieves itching by depressing cutaneous sensory receptors.
(d) *Astringent drug.* A drug that is applied topically (externally) to the skin or mucous membranes for a local and limited protein coagulant effect.
(e) *External use.* Topical application of an anorectal drug product to the skin of the perianal area and/or the skin of the anal canal.
(f) *Intrarectal use.* Topical application of an anorectal drug product to the mucous membrane of the rectum.
(g) *Keratolytic drug.* A drug that causes desquamation (loosening) and debridement or sloughing of the surface cells of the epidermis.
(h) *Local anesthetic drug.* A drug that produces local disappearance of pain, burning, itching, irritation, and/or discomfort by reversibly blocking nerve conduction when applied to nerve tissue in appropriate concentrations.
(i) *Protectant drug.* A drug that provides a physical barrier, forming a protective coating over skin or mucous membranes.
(j) *Vasoconstrictor.* A drug that causes temporary constriction of blood vessels.