Federal regulations · Through 2026-08-25 · Newer source version available

21 CFR 526.1130: Hetacillin.

(a) Specifications. Each single-dose, 10-milliliter syringe contains hetacillin potassium equivalent of 62.5 milligrams (mg) ampicillin.
(b) Sponsor. See No. 000010 in § 510.600(c) of this chapter.
(c) Related tolerances. See § 556.316 of this chapter.
(d) Conditions of use in lactating cows—(1) Amount. Infuse the contents of one syringe (equivalent to 62.5 mg ampicillin) into each infected quarter. Repeat at 24-hour intervals for a maximum of 3 treatments.
(2) Indications for use. For the treatment of acute, chronic, or subclinical mastitis in lactating cows caused by susceptible strains of Streptococcus agalactiae, Streptococcus dysgalactiae, Staphylococcus aureus, and Escherichia coli.
(3) Limitations. Milk that has been taken from animals during treatment and for 72 hours (6 milkings) after the latest treatment must not be used for food. Treated animals must not be slaughtered for food until 10 days after the latest treatment. Federal law restricts this drug to use by or on the order of a licensed veterinarian.

Where this section sits in the code

Title 21—Food and Drugs
CHAPTER I—FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES
SUBCHAPTER E—ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS
PART 526—INTRAMAMMARY DOSAGE FORM NEW ANIMAL DRUGS

(a) Specifications. Each single-dose, 10-milliliter syringe contains hetacillin potassium equivalent of 62.5 milligrams (mg) ampicillin.

(b) Sponsor. See No. 000010 in § 510.600(c) of this chapter.

(d) Conditions of use in lactating cows—(1) Amount. Infuse the contents of one syringe (equivalent to 62.5 mg ampicillin) into each infected quarter. Repeat at 24-hour intervals for a maximum of 3 treatments.

(2) Indications for use. For the treatment of acute, chronic, or subclinical mastitis in lactating cows caused by susceptible strains of Streptococcus agalactiae, Streptococcus dysgalactiae, Staphylococcus aureus, and Escherichia coli.

(3) Limitations. Milk that has been taken from animals during treatment and for 72 hours (6 milkings) after the latest treatment must not be used for food. Treated animals must not be slaughtered for food until 10 days after the latest treatment. Federal law restricts this drug to use by or on the order of a licensed veterinarian.

Collected 2026-08-27T02:24:47Z. Source file · JSON

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