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ingredients and processes
Official drug products and finished devices are prepared from ingredients that meet the requirements of the compendial monographs for those individual ingredients for which monographs are provided (see also NF 26). Generally, nutritional and dietary supplements are prepared from ingredients that meet requirements of the compendial monographs for those ingredients for which monographs are provided, except that substances of acceptable food grade quality may be used in the event of a difference.
Official substances are prepared according to recognized principles of good manufacturing practice and from ingredients complying with specifications designed to ensure that the resultant substances meet the requirements of the compendial monographs (see also Foreign Substances and Impurities under Tests and Assays).
Preparations for which a complete composition is given in this Pharmacopeia, unless specifically exempted herein or in the individual monograph, are to contain only the ingredients named in the formulas. However, there may be deviation from the specified processes or methods of compounding, though not from the ingredients or proportions thereof, provided the finished preparation conforms to the relevant standards laid down herein and to preparations produced by following the specified process.
The tolerances specified in individual monographs and in the general chapters for compounded preparations are based on attributes of quality such as might be expected to characterize an article compounded from suitable bulk drug substances and ingredients in accordance with the procedures provided or under recognized principles of good pharmaceutical practice as described in this Pharmacopeia (see Pharmaceutical Compounding—Nonsterile Preparations 795) and elsewhere.
Monographs for preparations intended to be compounded pursuant to prescription may contain assay methods. Assay methods are not intended for evaluating a compounded preparation prior to dispensing. Assay methods are intended to serve as the official test methods in the event of a question or dispute as to whether the compounded preparation complies with official standards.
Where a monograph on a preparation calls for an ingredient in an amount expressed on the dried basis, the ingredient need not be dried prior to use if due allowance is made for the water or other volatile substances present in the quantity taken.
Unless specifically exempted elsewhere in this Pharmacopeia, the identity, strength, quality, and purity of an official article are determined by the definition, physical properties, tests, assays, and other specifications relating to the article, whether incorporated in the monograph itself, in the General Notices, or in the section General Chapters.
Water— Water used as an ingredient of official preparations meets the requirements for Purified Water, for Water for Injection, or for one of the sterile forms of water covered by a monograph in this Pharmacopeia.
Potable water meeting the requirements for drinking water as set forth in the regulations of the U.S. Environmental Protection Agency may be used in the preparation of official substances.
Alcohol— All statements of percentages of alcohol, such as under the heading Alcohol content, refer to percentage, by volume, of C2H5OH at 15.56. Where reference is made to “C2H5OH,” the chemical entity possessing absolute (100 percent) strength is intended.
Alcohol— Where “alcohol” is called for in formulas, tests, and assays, the monograph article Alcohol is to be used.
Dehydrated Alcohol— Where “dehydrated alcohol” (absolute alcohol) is called for in tests and assays, the monograph article Dehydrated Alcohol is to be used.
Denatured Alcohol— Specially denatured alcohol formulas are available for use in accordance with federal statutes and regulations of the Internal Revenue Service. A suitable formula of specially denatured alcohol may be substituted for Alcohol in the manufacture of Pharmacopeial preparations intended for internal or topical use, provided that the denaturant is volatile and does not remain in the finished product. A finished product that is intended for topical application to the skin may contain specially denatured alcohol, provided that the denaturant is either a normal ingredient or a permissible added substance; in either case the denaturant must be identified on the label of the topical preparation. Where a process is given in the individual monograph, the preparation so made must be identical with that prepared by the given process.
Added Substances— An official substance, as distinguished from an official preparation, contains no added substances except where specifically permitted in the individual monograph. Where such addition is permitted, the label indicates the name(s) and amount(s) of any added substance(s).
Unless otherwise specified in the individual monograph, or elsewhere in the General Notices, suitable substances such as antimicrobial agents, bases, carriers, coatings, colors, flavors, preservatives, stabilizers, and vehicles may be added to an official preparation to enhance its stability, usefulness, or elegance or to facilitate its preparation. Such substances are regarded as unsuitable and are prohibited unless (a) they are harmless in the amounts used, (b) they do not exceed the minimum quantity required for providing their intended effect, (c) their presence does not impair the bioavailability or the therapeutic efficacy or safety of the official preparation, and (d) they do not interfere with the assays and tests prescribed for determining compliance with the Pharmacopeial standards.
Nutritional and Dietary Supplements— Unless otherwise specified in the individual monograph, or elsewhere in the General Notices, consistent with applicable regulatory requirements, suitable added substances such as bases, carriers, coatings, colors, flavors, preservatives, and stabilizers may be added to a nutritional supplement preparation to enhance its stability, usefulness, or elegance, or to facilitate its preparation. Such added substances shall be regarded as suitable and shall be permitted unless they interfere with the assays and tests prescribed for determining compliance with Pharmacopeial standards.
Additional Ingredients— Additional ingredients, including excipients, may be added to nutritional supplement preparations containing recognized nutrients, consistent with applicable regulatory requirements, provided that they do not interfere with the assays and tests prescribed for determining compliance with Pharmacopeial standards.
Inert Headspace Gases— The air in a container of an article for parenteral use may be evacuated or be replaced by carbon dioxide, helium, or nitrogen, or by a mixture of these gases, which fact need not be declared in the labeling.
Colors— Added substances employed solely to impart color may be incorporated into official preparations, except those intended for parenteral or ophthalmic use, in accordance with the regulations pertaining to the use of colors issued by the FDA, provided such added substances are otherwise appropriate in all respects. (See also Added Substances under Injections 1.)
Ointments and Suppositories— In the preparation of ointments and suppositories, the proportions of the substances constituting the base may be varied to maintain a suitable consistency under different climatic conditions, provided the concentrations of active ingredients are not varied and the bioavailability, therapeutic efficacy, or safety of the preparation is not impaired.