An Evidence-based Foundation for Safe and Effective Drug Therapy
With the 2025 edition, AHFS Drug Information ® ( AHFS ® DI ™) marks 66 years of continuous publication. The mission of AHFS ® DI ™is to provide an evidence-based foundation for safe and effective drug therapy. Widely trusted for its established record and rigorous editorial process, AHFS ® DI ™has remained true to its mission since the first edition in 1959. This notable achievement has gained AHFS ® DI ™the unique distinction of being the longest published federally designated drug compendium issued by a scientific and professional society.
AHFS ®DI ™is a collection of drug monographs kept current by ongoing electronic updates and by a revised master print volume issued annually. The AHFS ®DI ™database is maintained continuously throughout the year and updates are issued frequently in electronic formats. (See AHFS® Clinical Drug Information™ [AHFS® CDI™].)
AHFS ® was initially published as an adaptation from the Hospital Formulary of Selected Drugs by Don E. Francke, and the compendium has its roots in the hospital formulary system. The evidence-based assessments of medically accepted uses of drugs by AHFS ® predated the US Food and Drug Administration's (FDA's) own authority to evaluate drug effectiveness claims, and established AHFS ® as one of the first authoritative sources of critical evaluations of drug therapy. Today, it is the sole independent, non-commercial source of such evaluations in the US.
AHFS® Patient Medication Information (PMI)
ASHP has a long history of providing patients with meaningful information about medications. AHFS® Patient Medication Information ( PMI ) originated in 1976 as a collaboration among ASHP, the American Hospital Association (AHA), the US Department of Health, and Human Services (DHHS), and the US Centers for Disease Control and Prevention (CDC). It is the only compendium-based PMI database published by a professional and scientific society in the US.
The trust placed in AHFS ® PMI ™has resulted in a strategic alliance with the National Library of Medicine, an institute within the National Institutes of Health (NIH). AHFS ® PMI ™, hosted by the National Library of Medicine on MedlinePlus® and MedlinePlus® Connect, is one of few sites of trusted, accurate PMI, provided in both English and Spanish, with an outreach to over 100 million consumers annually. AHFS ® PMI ™also has been adopted as the trusted source of PMI by Sonifi®, a leading provider of bedside patient engagement and education resources in hospitals. This service focuses on improving patient satisfaction, outcomes, and quality as measured by the Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS) survey, care measures, and other indicators. Lastly, AHFS ® PMI ™is accessible through ASHP's own website—[Web].
AHFS ®PMI ™also includes links within the context of each of its drug monographs in support of CDC's PROTECT initiative on safe medication use. Through PROTECT, CDC, the Consumer Healthcare Products Association Educational Foundation, and other organizations support the Up and Away and Out of Sight campaign aimed at educating families and other caregivers about the importance of storing medications in a safe place to prevent inadvertent overdoses by children.
Off-Label Drug Reviews for Oncology
In 2008, AHFS ® DI ™introduced a process for publishing structured, codified, evidence-based determinations for off-label cancer uses. The decision to create a separate method resulted from the unique characteristics of evidence-based decisions that are applied to serious and life-threatening conditions such as cancer. This process supplements the long-standing evidence-based process used by AHFS® to evaluate off-label uses of drugs and biologics. The cancer-specific codified method developed by AHFS® is consistent with distinctions applied to evidence-based assessments of cancer treatments by other authoritative sources such as the National Cancer Institute (NCI) and FDA.
The principles of the AHFS ® DI ™evidence-based editorial development process have not changed with this oncology process. However, the codified determinations supplement and enhance the traditional AHFS ® DI ™evaluation of off-label uses with structured determinations that summarize ongoing assessments of new and changing evidence. ASHP appointed an Oncology Expert Committee, comprised of oncologists, oncology pharmacists, and oncology nurses, to assist with the independent review and final recommendations for off-label cancer determinations. Final decisions are made solely by the Oncology Expert Committee for determinations emanating from this supplementary process for oncology uses and by AHFS® staff for other information. All processes related to the review and publication of determinations are transparent and designed to mitigate any potential conflict of interest in order to preserve the integrity of AHFS ® DI ™and to minimize bias.
Federal regulations for transparency and conflict of interest disclosure and management became effective January 1, 2010 for off-label oncology determinations. AHFS® employs a process for evaluating therapies that is publicly transparent as defined by CFR Section 414.930(a) and that includes criteria used to evaluate the use, a listing of evidentiary materials reviewed by the compendium, and a listing of all individuals who participated substantively in the development, review, or disposition of the request. In the case of balloted determinations made by the AHFS® Oncology Expert Committee, conflict of interest disclosure policies follow the definition of a publicly transparent process for identifying potential conflicts of interest as established in this section of the CFR.
Documents describing this process for off-label oncology uses, including levels of evidence, transparency, and conflict of interest disclosure and management, may be viewed under the Off-label Uses section of the AHFS ® DI ™website at [Web]. Details about specific final determinations of medical acceptance for off-label oncology uses may also be accessed at this website location.
Information included in AHFS ® DI ™shapes treatment decisions made by clinicians and influences public and private health-care policies and decisions. As a result, it is important that the information be authoritative, objective, and free of undue influence from pharmaceutical companies and other third parties who may seek to use the compendium to promote their own vested interests.
AHFS ®DI ™is the only remaining official drug compendium published by a non-commercial, nonprofit, professional and scientific society. ASHP is the national professional organization that represents pharmacists who serve as patient care providers on healthcare teams in acute and ambulatory settings spanning the full spectrum of medication use. ASHP has an over 80 year history of fostering evidence-based medication use and patient medication safety. AHFS ®DI ™and PMI ™are published in part to support the mission of pharmacists in helping people achieve optimal health outcomes.
AHFS ®DI ™is published by ASHP under the authority of its elected Board of Directors. As such, the Board exercises oversight through its ongoing Society considerations. This oversight by the Board also involves review and approval of relevant recommendations originating from its appointed Council on Therapeutics and the advisory and best practices developments of its other Councils, House of Delegates, and other policy-recommending bodies.
ASHP considers it essential that interactions between AHFS® staff and pharmaceutical companies be limited to the legitimate exchange of the scientific and medical information needed to fulfill the mission of AHFS ® DI ™. To maintain independence from the undue influence of the promotional interests of pharmaceutical companies, communications are directed to the scientific and medical information areas within the companies; contact with marketing areas is avoided.
ASHP holds in high regard the responsibilities attendant to the public and private trust placed in the evidence-based editorial deliberations of AHFS ® DI ™. As such, ASHP also considers it essential to protect the integrity and independence of the editorial decisions of AHFS® staff by separating the Society's business activities with pharmaceutical companies (e.g., exhibits at educational meetings, journal advertising) from the editorial activities of its drug compendium. An editorial independence statement, approved by ASHP's Board of Directors and available at [Web], outlines the principles that AHFS® staff apply in ensuring such independence.
Comparative, Unbiased, Evaluative Drug Information
AHFS ®DI ™is a tested and proven source of comparative, unbiased, and evidence-based drug information containing a monograph on virtually every molecular drug entity available in the US. Drug monographs are prepared by a professional editorial and analytical staff, who critically evaluate published evidence on the drug.
AHFS ®DI ™monographs incorporate information from pertinent references in the literature and expert therapeutic guidelines. The monographs also address the labeling approved by FDA, in some cases challenging outdated and clinically irrelevant information that may persist in the approved labeling. AHFS ®DI ™monographs continue to include information on uses, dosages, and routes and/or methods of administration that may not be included in the FDA-approved labeling for the drug (“off-label/unlabeled uses”). Monographs may incorporate information from numerous published references.
Widely Used in Print and Electronic Formats
AHFS ®DI ™and its point-of-care derivative database AHFS ®DI ™Essentials ™are used widely as sources of authoritative drug information by physicians, pharmacists, dentists, nurses, and other health care professionals, by schools of pharmacy, nursing, and medicine, and are available in a variety of formats. Electronic formats include UpToDate® Lexidrug™; First DataBank's AHFS Drug Information® monographs available from multiple vendors; AHFS Drug Information ® from STAT!Ref®, Pepid's Pharmacist Pro with AHFS ® DI ™, and MedicinesComplete®; Drug Information Fulltext® ( DIF ®); and AHFS ® DI ™Powered by Skyscape Medpresso. AHFS ® DI ™Essentials ™is available electronically in online and mobile applications.
In hospitals, clinics, extended-care facilities, nursing homes, health maintenance organizations, and other organized health-care settings, AHFS ® DI ™is accessible in patient-care areas for ready use by physicians, nurses, pharmacists, and other healthcare professionals. AHFS ® DI ™also is used in community pharmacies, chain drugstores, and other ambulatory care and professional practice settings and is available in most medical libraries.
AHFS® Clinical Drug Information (AHFS® CDI)
In 2016, ASHP released a comprehensive, electronic suite of its leading drug information databases, including AHFS ® DI ™. AHFS® Clinical Drug Information™ (AHFS® CDI™), expands the availability of these trusted ASHP resources, providing clinicians with real-time drug and safety updates and direct links to a vast number of supporting evidence sources, as well as easy access to the detailed drug information and in-depth coverage of off-label uses found in AHFS ® DI ™. In addition to the monographs of AHFS ® DI ™, subscribers to AHFS® CDI™ have access to AHFS ® DI ™Essentials ™, which offers quick, point-of-care answers. Additional ASHP drug information resources are included in the product, including ASHP's drug shortages resources (which are prepared in conjunction with the University of Utah Drug Information Service) and the AHFS Pharmacologic-Therapeutic Classification system. AHFS® CDI™ features links to additional specialty databases of drug-specific information, including prescribing information, FDA's latest boxed warnings, safety labeling changes, REMS, pharmacogenomic data, a specialty breast-feeding database, and other clinical resources.
AHFS® Clinical Drug Information™ is available for individual and institutional subscribers via web browser and is mobile-optimized for use on iOS and Android devices. AHFS® CDI™also is available as an iOS app. In addition, the user interface will integrate into clinical workflow solutions in hospitals and ambulatory care settings. An application programming interface (API) is available.
AHFS ®DI ™is supported solely through subscriptions. AHFS ®DI ™has been officially adopted by the US Public Health Service and the Department of Veterans Affairs; recommended by the National Association of Boards of Pharmacy as part of the standard reference library; recommended by the American College of Physicians as part of a library for internists; included in the Standards for Medicare; approved by the American Pharmacists Association, American Health Care Association, American Hospital Association, and Catholic Health Care Association of the United States; recognized by the US Congress, CMS, AHIP, National Blue Cross and Blue Shield Association, National Association of Insurance Commissioners, and various third-party healthcare insurance providers for coverage decisions on off-label (unlabeled) uses; and included as a required or recommended standard reference for pharmacies in many states.
The authority of AHFS ® DI ™also includes Federal recognition through legislation and regulation as an “official” compendium for information on medically accepted uses of drugs. The Federal compendial recognition for AHFS ® DI ™originated in the Medicare Catastrophic Coverage Act. CMS determined that AHFS ® DI ™met the compendial selection criteria established by Congress and adopted the compendium for carrying out certain aspects of the Act and in meeting the need of the US Secretary of HHS to establish standards based on accepted medical practice for the prescribing, dispensing, and utilization of covered drugs. This established the Federal precedent for use of AHFS ® DI ™as a compendial standard in subsequent legislative and regulatory initiatives, including for drug coverage under Medicaid and Medicare Parts B and D.
Continuously Updated and Revised
The AHFS ® DI ™database and annual print edition are updated extensively, incorporating revised information on uses, therapeutic perspectives, cautions, drug interactions, new products, and other new developments. In addition, the database is expanded by dozens of new drug monographs over the course of the year.
The AHFS® DI™ database is also revised and updated extensively throughout the year to address evolving information on medication safety. Manufacturer labeling, FDA safety communications such as MedWatch notices and Risk Evaluation and Mitigation Strategy (REMS) information, published studies and reports, and other safety information are evaluated and addressed. Through semi-automated processes, much of this information is updated on an ongoing basis in electronic versions of the database to reflect more contemporaneous changes made by FDA.
Recognition and Granularity of the AHFS® Pharmacologic-Therapeutic Classification©
The AHFS ® Pharmacologic-Therapeutic Classification© is the most widely used formulary-structure drug classification in the US and Canada. The AHFS® classification is maintained continuously by ASHP and allows the grouping of drugs with similar pharmacologic, therapeutic, and/or chemical characteristics in a 4-tier hierarchy.
For details on class changes and drug monograph assignments and reassignments throughout the year, see the link to the AHFS® Classification Drug Assignments and Reassignments on the homepage at [Web].
In the printed version of the classification in AHFS ® DI ™, a drug monograph generally is only printed under one classification; however, multiple classifications may apply based on a drug's pharmacology or therapeutic uses. Multiple classifications for a drug in print are represented by cross-references in the table of contents for each chapter/class. If cross-referenced, the drug name is given followed by the classification number that it is printed under. Electronically, all applicable classes for a drug are listed.
CMS' “Guidelines for Reviewing Prescription Drug Plan Formularies and Procedures” and “Medicare Prescription Drug Benefit Manual: Part D Drugs and Formulary Requirements” describe use of the AHFS ® Pharmacologic-Therapeutic Classification© as the only named alternative to USP's Model Guidelines for use by prescription drug plans (PDPs) in implementing the formulary portion of the outpatient prescription drug benefit in the Medicare Modernization Act (MMA) of 2003. These Guidelines are part of the MMA Final Guidelines for Formularies that address the “CMS Strategy for Affordable Access to Comprehensive Drug Coverage.”
The AHFS® Classification is a registered external code system in the HL7 Vocabulary Repository. (OID: 2.16.840.1.113883.6.234.)
The AHFS® Classification also is an approved value code of the External Code List for use in the Formulary & Benefit, Telecommunication, Post-Adjudication, & SCRIPT e-Prescribing standards of the National Council for Prescription Drug Programs (NCPDP).
Selected Content in the Print Edition of AHFS® DI
As the number of FDA-approved drugs has increased and information about existing drugs has expanded, it has been necessary to omit an increasing number of monographs from the print version of AHFS ® DI ™each year. Considerations used to select monographs for print include the following:
The Editorial staff wishes to express appreciation to the many consultants and reviewers for their excellent guidance and cooperation and to our subscribers for their support and comments.
Some monographs have been omitted from the print version of AHFS ® DI ™because of space limitations. Copies of these monographs are available on the “Print Subscribers” page of the AHFS Drug Information® website, [Web], in the “Electronic Only Monographs” section. A username and password are required to access the subscriber-only portions of the website. For the 2025 edition, the username and password for accessing electronic-only content are as follows:
Associated index entries for monographs that appear on the website are followed by the symbol “” rather than by a page number. This symbol refers the user to a footnote in the index that also provides the above username and password for the 2025 edition.
AHFS® Drug Information. © Copyright, 1959-2025, Selected Revisions January 10, 2025. American Society of Health-System Pharmacists, Inc., 4500 East-West Highway, Suite 900, Bethesda, MD 20814.