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An Overview of USP 797

USP <797> Overview Including Background and History

By Joseph P. Manfrida, Ph.D., EMLab P&K Analyst

What is USP ?
USP is a chapter of the United States Pharmacopeia - National Formulary (USP-NF). It was written by the national public standards setting organization known as the U. S. Pharmacopeia to regulate pharmaceutical laboratories that produce and disseminate compounded sterile preparations (CSPs). USP covers a wide variety of topics including the training of compounding personnel, how sterile preparations are to be handled and stored, the design of facilities, and the establishment and maintenance of suitably clean environmental conditions for the production of CSPs. USP is unique among prior documents addressing these issues in that it was written to be an enforceable set of standards that can be adopted by state pharmacy regulating agencies as law.

A Brief History of CSP Regulation
USP was written after a long history of earlier attempts to improve patient safety had failed. Public and government attention was originally drawn to the problem of contaminated and improperly handled CSPs during the 1960's and 1970's. The American Society of Health-System Pharmacists (ASHP) released a Technical Assistance Bulletin and the U. S. Pharmacopeia published USP-NF chapter in response to the problem in the early 1990's. Both of these publications were recommendations and guidelines and were not designed to be enforceable by law. Unfortunately, the results were less than what the releasing organizations had hoped for. In the period from June through December of 2001, the FDA found that 34% of CSPs tested had product deficiencies.1 Additional problems were found with pharmacy practices when compared to the guidelines and recommendations issued by the ASHP. For example, a survey of pharmacy personnel and practices in 2003 determined that only "5% of pharmacies that compounded risk-level-1 preparations were found to be compliant with garb requirements."2 Clearly the recommendations and guidelines issued by the ASHP and the USP were insufficient to assure the safety of public health. Since voluntary compliance was not up to the task, the USP set out to create a set of legally enforceable regulations that could be adopted by state boards of pharmacy to use as a basis for accreditation of health care organizations.

In 1938 the U.S. Congress passed the Federal Food, Drug and Cosmetic Act.3 This Act established the USP-NF as the official set of baseline standard practices that must be followed by all pharmacies in the United States. All of the chapters numbered between and are enforceable by the FDA and can be used as the basis for state and federal laws and accreditation standards. Publication of a chapter on the preparation of CSPs with the chapter number in 2004 effectively established legally enforceable standards for the preparation of CSPs. Since its original publication, USP has been revised once.

What types of facilities need to be compliant with USP ?
According to USP , the standards outlined in the chapter apply to all facilities and personnel that prepare CSPs. A CSP is defined as "Compounded biologics, diagnostics, drugs, nutrients, and radio-pharmaceuticals... that must be sterile when they are administered to patients," and "Manufactured sterile products that are either prepared strictly according to the instructions appearing in manufacturers' approved labeling... or prepared differently than published in such labeling."4 This definition means that USP applies to a wide variety of medical facilities that regularly produce injections, inhalants, baths, soaks, drops and ointments. In the case of large hospitals with multiple pharmacies and drug preparation areas, USP can apply to multiple areas within a single medical facility. It is very important to note that whether or not USP applies to a given facility is not determined by the facility's size or the number of patients it serves. The applicability of USP is strictly determined by the nature of what a facility is preparing. Any facility that prepares CSPs as defined by USP is subject to the standards and practices it delineates.

Why should a facility be USP compliant?
Any chapter in the USP-NF numbered through is enforceable by the Environmental Protection Agency (EPA). When a facility is investigated in response to a medical incident, the EPA may fine the facility for violations of USP . Additionally, many state boards of pharmacy have either adopted USP as part of their pharmacy certification standards or are in the process of doing so. States which have made USP part of their standards include: Arkansas, Indiana, Kansas, Louisiana, Maryland, Massachusetts, Nevada, North Carolina, Ohio, Oklahoma, South Carolina, South Dakota, Texas, Utah, Virginia, and West Virginia.5 The Joint Commission on Accreditation of Healthcare Organizations (JCAHO) surveys medical facilities for USP compliance. Many of the requirements outlined by USP are also mandated by or exceeded by the JCAHO's Medication Management Standard. Finally, it should be noted that in the past lawyers have used USP-NF chapters as examples of best practices in civil lawsuits.6 Any organization that fails to meet the practices outlined in the USP-NF risks legal liability.

Overview of USP-NF chapter
USP concerns itself with many aspects of CSP preparation and storage. The document can be divided into three sections, CSP handling, personnel training, and environmental sterility.

How CSPs are to be handled is based on the risk classification of the preparation in question. Low risk level preparations are compounded entirely in high sterility environments using materials that are themselves already sterile and produced only in single doses. Moderate risk preparations are similar to low risk preparations with the exception that they are either subject to a longer process of manipulation during preparation, or they are combined into a single larger preparation either for administration to multiple patients or to a single patient for an extended duration. High risk CSPs are those that are either composed of non-sterile components or are exposed to non-sterile conditions during preparation, thereby requiring them to be sterilized after compounding prior to use. Each of these different classifications of preparation has increasingly stringent rules for their preparation that are to be followed. These rules apply both to the actual handling of the CSP and to the training of personnel who prepare them.

The proper training of personnel who handle CSPs is a running theme throughout the document. While there are specific sections dedicated just to the training of personnel and the evaluation of their performance, USP stresses the importance of having well trained personnel in all parts of the document. In order to train and monitor personnel performance in the most efficacious manner possible, USP requires personnel to regularly undergo media fill tests. In these tests personnel are required to perform the entire procedure for compounding a given CSP using soybean – casein digest medium in place of the normal ingredients of the preparation. The test is run using conditions as closely emulating actual compounding as is possible. After the procedure has been executed, the test compound is incubated. Microbial growth indicates that the test has failed; lack of growth indicates that the subject has passed the test. In the event of a media fill test failure both the compounding individual and the process itself should be evaluated for areas that can be improved.

A significant portion of USP is dedicated to establishing and maintaining sterile conditions in the CSP production area. Laboratory design and engineering control placement are discussed in order to facilitate maintenance of sterile conditions in the CSP compounding area. Additionally, practices for maintaining aseptic conditions in a functioning laboratory are outlined. These practices include testing for viable and nonviable particulates in the air and on surfaces at least once every six months. Non-viable particles can be measured directly using electronic air samplers. Viable particles are measured by sampling a volume of air and allowing any particles in the sample to impact on TSA (for the growth of bacteria) and MEA (for the growth of fungi). Swabs are used to collect samples off from surfaces. Samples are taken at the critical site of compounding where the CSPs are actually processed, the buffer area immediately around it and the ante – area that precedes the buffer area. The amount of nonviable and viable particles detected by the testing are compared to Table 1 and an ISO Class is assigned to each area. Facilities that are operating within the parameters of USP will have a critical site of ISO Class 5, a buffer area of ISO Class 7 and an ante – area of ISO Class 8. If a facility is operating outside of these parameters corrective action should be taken to bring the compounding facility back into compliance.

The designation of USP as regulatory law enforceable by the FDA and its adoption as part of the accreditation standards for pharmacies in an increasing number of states has placed extensive pressure on medical facilities and organizations to meet or exceed the standards it outlines. Doing this requires a long-term commitment to regular environmental monitoring, development of expertise, and an ability to efficiently deploy resources in the pharmaceutical laboratory where they will have the greatest effect. The USP 797 program at EMLab P&K is dedicated to providing the material resources and technical expertise needed to meet these challenges. We will continue to provide the same commitment to quality that you have come to expect from EMLab P&K in our other services.

Table 1. ISO Classes and particulate levels

ISO Class ≥ 0.5 µm Nonviable
Viable Airborne
Viable Surface**
(cfu/contact plate)
5 3,520 ≤ 1 ≤ 3
7 352,000 ≤ 10 ≤ 5
8 3,520,000 ≤ 100 ≤ 100

* cfu = colony forming units
** Contact plate areas vary from 24 to 30 cm2. When swabbing is used in sampling, the area covered should be at least 24 cm2 but no larger than 30 cm2.

1. US Food and Drug Administration. Report: Limited FDA Survey of Compounded Drug Products. Accessed 8/19/2009.

2. Morris A.M., Schneider P.J., Pedersen C.A et al. National survey of quality assurance activities for pharmacy - compounded sterile preparations. American Journal of Health System Pharmacists. 2003; 60:2567-2576

3. Kastango, Eric S. The ASHP Discussion Guide on USP Chapter , Compounding Sterile Preparations, p. 1-13. Accessed 8/19/2009.

4. The United States Pharmacopeial Convention. Pharmaceutical Compounding - Sterile Preparations. National Formulary. 2008, p. 1-61.

5. Jorgenson, James. USP 797 and the NIOSH Alert: A Q&A update for oncology pharmacy and cancer program administrators. Oncology Issues, September/October 2006, p. 38-41.

6. Kastango, p. 6. Accessed 8/19/2009.


This article was originally published on August 2009.