21 CFR § 556.344 - Ivermectin.

---
identifier: "/us/cfr/t21/s556.344"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "21 CFR § 556.344 - Ivermectin."
title_number: 21
title_name: "Food and Drugs"
section_number: "556.344"
section_name: "Ivermectin."
chapter_name: "FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES"
subchapter_number: "E"
subchapter_name: "ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS"
part_number: "556"
part_name: "TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD"
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. 342, 360b, 371."
regulatory_source: "84 FR 32993, July 11, 2019, unless otherwise noted."
cfr_part: "556"
---


# 556.344 Ivermectin.

(a) *Acceptable daily intake (ADI).* The ADI for total residue of ivermectin is 5 µg/kg of body weight per day.

(b) *Tolerances.* The tolerances for 22,23-dihydroavermectin B<sub>1</sub>a (marker residue) are:

(1) *American bison.* Liver (target tissue): 15 ppb.

(2) *Cattle.* (i) Liver (target tissue): 1.6 ppm.

(ii) Muscle: 650 ppb.

(3) *Reindeer.* Liver (target tissue): 15 ppb.

(4) *Sheep.* Liver (target tissue): 30 ppb.

(5) *Swine.* (i) Liver (target tissue): 20 ppb.

(ii) Muscle: 20 ppb.

(c) *Related conditions of use.* See §§ 520.1192, 520.1195, 520.1197, 522.1192, 522.1193, 524.1193, and 558.300 of this chapter.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]