From the vendor:
The United States Pharmacopeia and The National Formulary (USP–NF) is a book of public pharmacopeial standards for chemical and biological drug substances, dosage forms, compounded preparations, excipients, medical devices, and dietary supplements.
USP–NF is a combination of two compendia, the United States Pharmacopeia (USP) and the National Formulary (NF). Monographs for drug substances, dosage forms, and compounded preparations are featured in the USP. Monographs for dietary supplements and ingredients appear in a separate section of the USP. Excipient monographs are in the NF.
The USP-NF is an annual publication that is revised via two supplementary publications per year which are mailed to subscribers (the "Supplements"); as well as various errata, bulletins, and announcements, which are posted on the vendor's website. A subscription to the online version provides access to the current edition of the text (the main volume as well as the two Supplements), and includes icons which identify and link to relevant revisions posted on the vendor's website. An online subscription also provides access to the unofficial text text of the next year's volume, once it's available.
The vendor moved their online content to a new platform over the summer of 2018 and, as of December 1st 2018, the old platform has been retired. Subscribers can find more information on their current subscription pages.
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