Standards for Veterinary Drugs

Consistent with its commitment to provide public standards for the quality, consistency, purity, identity, and strength of all medicines, USP is advancing its standards for drugs for veterinary use. These standards include monographs and general chapters (including those devoted to veterinary drug topics) applicable to any articles recognized in the United States Pharmacopeia–National Formulary (USP–NF), whether in the form of a manufactured product or a compounded preparation. USP has been active in setting standards for veterinary drugs for many years and is committed to help provide quality medicine to veterinary patients.

Current Activities

New General Chapter <1236> Solubility Determination

The new USP General Chapter <1236> Solubility Determination was proposed in Pharmacopeial Forum 43(2) [March – April 2017. This chapter provides an overview of the concepts and equations that are relevant to solubility measurements. The chapter also briefly describes typical experimental methods used to assess solubility determination of pharmaceutical materials. For the determination of equilibrium solubility the chapter describes the Saturation Shake-Flask Method. For the determination of apparent solubility, the chapter describes the methods by potentiometric titration and by turbidimetry. In addition, the chapter lists the composition of bio-relevant media and conditions that can be used to determine the solubility of compounds in conditions that try to simulate in-vivo conditions in humans, dogs and cattle.

The development of this chapter is a joint effort of the Solutions sub-committee, under the USP Physical analysis Expert Committee and the Solubility Criteria for Veterinary Drugs Expert Panel, under the USP Pharmaceutical Dosage Forms Expert Committee. All the activities carried out by the Solubility Criteria for Veterinary Drugs Expert Panel that culminated in the new USP general chapter on solubility are listed below under (see Project Solubility Criteria for Veterinary Drugs).

Project Solubility Criteria for Veterinary Drugs

The summary of the discussions held during the Workshop on Solubility Criteria for Veterinary Products  and the  Stimuli articles provide explanations for the approaches included in the new USP General Chapter <1236> Solubility Determination.  This information can be found below:

The report from the USP Workshop on In Vitro Testing for Meeting Future Challenges for Veterinary Dosage Forms is available at:

For additional information, contact Margareth Marques, Ph.D., Senior Scientific Liaison ( or 301-816-8106).

USP General Chapter <1152> Animal Drugs for Use in Animal Feeds

USP General Chapter, <1152> Animal Drugs for Use in Animal Feeds (Pharmacopeial Forum, Vol. 40, No. 1 [Jan.–Feb. 2014]), addresses naming conventions, labeling and packaging, and the preparation of Type A medicated articles and Type B and Type C medicated feeds. This General Chapter replaces the Veterinary Drugs and Drug Products Delivered in Animal Feeds section that previously appeared in informational General Chapter <1151> Pharmaceutical Dosage Forms. The information provided in USP General Chapter <1152> draws on 21 CFR sections 558.3 and 510.455.
For additional information, contact William Brown, Senior Scientific Liaison ( or 301-816-8380).

Compounding Monographs

The USP–NF includes standards of identity, strength quality, purity, packaging, and labeling for drug substances and products used in veterinary compounding. Additionally, USP takes an active role in supporting the public’s access to customized drug therapy by developing compounding preparation monographs for animal patients.

Manufactured Drugs and Drug Products Monographs

The USP–NF includes more than190 veterinary-specific monographs for FDA approved drug substances and drug products, and is actively engaged in developing additional monographs through both external industry sponsors and internal development (USP laboratories). Additionally, USP has identified more than 150 related monographs in need of modernization. Modernization opportunities include replacing titration assays, adding and updating procedures for impurities, and incorporating additional tests for Identification. Questions and comments, interpretation, applications, and proposed revisions for specific monographs:  Submit your inquiry using our WebForm or by emailing

Resources for the USP Monograph Development Process

Questions and comments, interpretation, applications, and proposed revisions for specific monographs: