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Title 21

Displaying title 21, up to date as of 10/09/2026. Title 21 was last amended 10/09/2026.
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§ 526.820 Erythromycin.

(a) Specifications.

(1) Each single-dose, 6-milliliter (mL) syringe contains 300 milligrams (mg) erythromycin (as the base).

(2) Each single-dose, 12-mL syringe contains 600 mg erythromycin (as the base).

(b) Sponsors. See Nos. 054771 and 061133 in § 510.600(c) of this chapter.

(c) Related tolerances. See § 556.230 of this chapter.

(d) Conditions of use for syringe described in paragraph (a)(1) of this section in lactating cows —

(1) Amount. Infuse the contents of one 6-mL syringe (300 mg erythromycin base) into each infected quarter. Repeat infusion at 12-hour intervals for a maximum of 3 infusions.

(2) Indications for use. For the treatment of mastitis due to Staphylococcus aureus, Streptococcus agalactiae, Streptococcus dysgalactiae, and Streptococcus uberis in lactating cows.

(3) Limitations. Milk taken from animals during treatment and for 36 hours (3 milkings) after the latest treatment must not be used for food. Federal law restricts this drug to use by or on the order of a licensed veterinarian.

(e) Conditions of use for syringe described in paragraph (a)(2) of this section in dry cows —

(1) Amount. Infuse the contents of one 12-mL syringe (600 mg erythromycin base) into each infected quarter at the time of drying off.

(2) Indications for use. For the treatment of mastitis due to Staphylococcus aureus, Streptococcus agalactiae, Streptococcus dysgalactiae, and Streptococcus uberis in dry cows.

(3) Limitations. For use in dry cows only. Federal law restricts this drug to use by or on the order of a licensed veterinarian.

[86 FR 13186, Mar. 8, 2021, as amended at 88 FR 14901, Mar. 10, 2023]