Pharmacopoeia

Pharmacopoeia (literally, the art of the drug compounder), in its modern technical sense, is a book containing directions for the identification of samples and the preparation of compound medicines, and published by the authority of a government or a medical or pharmaceutical society. The name has also been applied to similar compendiums issued by private individuals.

History
The earliest pharmacopoeia books were written by Muslim physicians. These included Abu-Rayhan Biruni in the 11th century, Ibn Baytar in the 14th century, and Ibn Zuhr in 1491.

The first work of the kind published under government authority appears to have been that of Nuremberg in 1542; a passing student named Valerius Cordus showed a collection of medical receipts, which he had selected from the writings of the most eminent medical authorities, to the physicians of the town, who urged him to print it for the benefit of the apothecaries, and obtained for his work the sanction of the senatus.

An earlier work, known as the Antidotarium Florentinum, had been published under the authority of the college of medicine of Florence.

The term pharmacopoeia first appears as a distinct title in a work published at Basel in 1561 by Dr A. Foes, but does not appear to have come into general use until the beginning of the 17th century.

Before 1542 the works principally used by apothecaries were the treatises on simples by Avicenna and Serapion; the De synonymis and Quid pro quo of Simon Januensis; the Liber servitoris of Bulchasim Ben Aberazerim, which described the preparations made from plants, animals and minerals, and was the type of the chemical portion of modern pharmacopoeias; and the Antidotarium of Nicolaus de Salerno, containing Galenical compounds arranged alphabetically. Of this, last work there were two editions in use &mdash; Nicolaus magnus and Nicolaus parvus: in the later several of the compounds described in the large edition were omitted and the formulae given on a smaller scale.

Until 1617 such drugs and medicines as were in common use were sold in England by the apothecaries and grocers. In that year the apothecaries obtained a separate charter, and it was enacted that no grocer should keep an apothecary’s shop. The preparation of physicians’ prescriptions was thus confined to the apothecaries, upon whom pressure was brought to bear to make them dispense accurately, by the issue of a pharmacopoeia in May 1618 by the College of Physicians, and by the power which the wardens of the apothecaries received in common with the censors of the College of Physicians of examining the shops of apothecaries within 7 m. of London and destroying all the compounds which they found unfaithfully prepared. This, the first authorized London Pharmacopoeia, was selected chiefly from the works of Mezue and Nicolaus de Salerno, but it was found to be so full of errors that the whole edition was cancelled, and a fresh edition was published in the following December. At this period the compounds employed in medicine were often heterogeneous mixtures, some of which contained from 20 to 70, or more, ingredients, while a large number of simples were used in consequence of the same substance being supposed to possess different qualities according to the source from which it was derived. Thus crabs’ eyes (i.e., gastroliths), pearls, oyster-shells and coral were supposed to have different properties. Among other ingredients entering into some of these formulae were the excrements of human beings, dogs, mice, geese and other animals, calculi, human skull and moss growing on it, blind puppies, earthworms, etc. Although other editions of the London Pharmacopoeia were issued in 1621, 1632, 1639 and 1677, it was not until the edition of 1721, published under the auspices of Sir Hans Sloane, that any important alterations were made. In this issue many of the ridiculous remedies previously in use were omitted, although a good number were still retained, such as dogs’ excrement, earthworms, and moss from the human skull; the botanical names of herbal remedies were for the first time added to the official ones; the simple distilled waters were ordered of a uniform strength; sweetened spirits, cordials and ratifias were omitted as well as several compounds no longer used in London, although still in vogue elsewhere. A great improvement was effected in the edition published in 1746, in which only those preparations were retained which had received the approval of the majority of the pharmacopoeia committee; to these was added a list of those drugs only which were supposed to be the most efficacious. An attempt was made to simplify further the older formulae by the rejection of superfluous ingredients. In the edition published in 1788 the tendency to simplify was carried out to a much greater extent, and the extremely compound medicines which had formed the principal remedies of physicians for 2000 years were discarded, while a few powerful drugs which had been considered too dangerous to be included in the Pharmacopoeia of 1765 were restored to their previous position. In 1809 the French chemical nomenclatuie was adopted, and in 1815 a corrected impression of the same was issued. Subsequent editions were published in 1824, 1836 and 1851.

The first Edinburgh Pharmacopoeia was published in 1699 and the last in 1841; the first Dublin Pharmacopoeia in 1807 and the last in 1850.

National Pharmacopoeia
The preparations contained in these three pharmacopoeias were not all uniform in strength, a source of much inconvenience and danger to the public, when powerful preparations such as dilute hydrocyanic acid were ordered in the one country and dispensed according to the national pharmacopoeia in another. As a result, the Medical Act of 1858 ordained that the General Medical Council should publish a book containing a list of medicines and compounds, to be called the British Pharmacopoeia, which would be a substitute throughout Great Britain and Ireland for the separate pharmacopoeias. Hitherto these had been published in Latin. The first British Pharmacopoeia was published in the English language in 1864, but gave such general dissatisfaction both to the medical profession and to chemists and druggists that the General Medical Council brought out a new and amended edition in 1867. This dissatisfaction was probably owing partly to the fact that the majority of the compilers of the work were not engaged in the practice of pharmacy, and therefore competent rather to decide upon the kind of preparations required than upon the method of their manufacture. The necessity for this element in the construction of a pharmacopoeia is now fully recognized in other countries, in most of which pharmaceutical chemists are represented on the committee for the preparation of the legally recognized manuals.

There are national and international pharmacopoeias, like the EU and the U.S. pharmacopoeias. All the pharmacopoeias were issued under the authority of government, and their instructions have the force of law in their respective territories, except that of the United States, which was prepared by commissioners appointed by medical and pharmaceutical societies, and has no other authority, although generally accepted as the national textbook.

International Pharmacopoeia
Increased facilities for travel have brought into greater prominence the importance of an approach to uniformity in the formulae of the more powerful remedies, in order to avoid danger to patients when a prescription is dispensed in a different country from that in which it was written. Attempts have been made by international pharmaceutical and medical conferences to settle a basis on which an international pharmacopoeia could be prepared, but due to national jealousies and the attempt to include too many preparations nothing has yet been achieved.

Nonetheless, some progress has been made under the banner of the ICH (International Convention on Harmonisation), a tri-regional organisation that represents the drug regulatory authorities of the European Union, Japan and the United States. Representatives from the Pharmacopoeias of these three regions have met twice yearly since 1990 in the Pharmacopoeial Discussion Group to try to work towards "compendial harmonisation"’. Specific monographs are proposed, and if accepted, proceed through stages of review and consultation leading to adoption of a common monograph that provides a common set of tests and specifications for a specific material. Not surprisingly, this is a slow process.

Preparations
The rapid increase in medical and pharmaceutical knowledge renders necessary frequent new editions of the national pharmacopoeias, the office of which is to furnish definite formulae for preparations that have already come into extensive use in medical practice, so as to ensure uniformity of strength, and to give the characters and tests by which their purity and potency may be determined. But each new edition requires several years to carry out numerous experiments for devising suitable formulae, so that the current Pharmacopoeia can never be quite up to date. This difficulty has hitherto been met by the publication of such nonofficial formularies as Squire's Companion to the Pharmacopoeia and Martindale: The complete drug reference (formerly Martindale's : The Extra Pharmacopoeia), in which all new remedies and their preparations, uses and doses are recorded, and in the former the varying strengths of the same preparations in the different pharmacopoeias are also compared (Squire's was incorporated into Martindal in 1952). The need of such works to supplement the Pharmacopoeia is shown by the fact that they are even more largely used than the Pharmacopoeia itself, the first issued in 18 editions and the second in 13 editions at comparatively short intervals. In the UK, the task of elaborating a new Pharmacopoeia is entrusted to a body of a purely medical character, and legally the pharmacist has not, contrary to the practice in other countries, a voice in the matter, notwithstanding the fact that, although the medical practitioner is naturally the best judge of the drug or preparations that will afford the best therapeutic result, he is not so competent as the pharmacist to say how that preparation can be produced in the most effective and satisfactory manner, nor how the purity of drugs can be tested.

The change occurred with the fourth edition of the British Pharmacopoeia in 1898. A committee of the Royal Pharmaceutical Society of Great Britain was appointed at the request of the General Medical Council to advise on pharmaceutical matters. A census of prescriptions was taken to ascertain the relative frequency with which different preparations and drugs were used in prescriptions, and suggestions and criticisms were sought from various medical and pharmaceutical bodies across the British Empire. As regards the purely pharmaceutical part of the work a committee of reference in pharmacy, nominated by the pharmaceutical societies of Great Britain and Ireland (as they were then), was appointed to report to the Pharmacopoeia Committee of the Medical Council.

Some difficulty has arisen since the passing of the Adulteration of Food and Drugs Act concerning the use of the Pharmacopoeia as a legal standard for the drugs and preparations contained in it. The Pharmacopoeia is defined in the preface as only "intended to afford to the members of the medical profession and those engaged in the preparation of medicines throughout the British Empire one uniform standard and guide whereby the nature and composition of, substances to be used in medicine may be ascertained and determined." It is obvious that it cannot be an encyclopaedia of substances used in medicine, and can only be used as a standard for the substances and preparations contained in it, and for no others. It has been held in the Divisional Courts (Dickins v. Randerson) that the Pharmacopoeia is a standard for official preparations asked for under their pharmacopoeial name. But there are many substances in the Pharmacopoeia which are not only employed in medicine, but have other uses, such as sulphur, gum benzoin, tragacanth, gum arabic, ammonium carbonate, beeswax, oil of turpentine, linseed oil, and for these a commercial standard of purity as distinct from a medicinal one is needed, since the preparations used in medicine should be of the highest possible degree of purity obtainable, and this standard would be too high and too expensive for ordinary purposes. The use of trade synonyms in the Pharmacopoeia, such as saltpetre for purified potassium nitrate, and milk of sulphur for precipitated sulphur, is partly answerable for this difficulty, and has proved to be a mistake, since it affords ground for legal prosecution if a chemist sells a drug of ordinary commercial purity for trade purposes, instead of the purified preparation which is official in the Pharmacopoeia for medicinal use. This would not be the case if the trade synonym were omitted. For many drugs and chemicals not in the Pharmacopoeia there is no standard of purity that can be used under the Adulteration of Food and Drugs Act, and for these, as well as for the commercial quality of those drugs and essential oils which are also in the Pharmacopoeia, a legal standard of commercial purity is much needed. This subject formed the basis of discussion at several meetings of the Pharmaceutical Society, and the results have been embodied in a work entitled Suggested Standards for Foods and Drugs, by C. G. Moor, which indicates the average degree of purity of many drugs and chemicals used in the arts, as well as the highest degree of purity obtainable in commerce of those used in medicine.

An important step has also been taken in this direction by the publication under the authority of the Council of the Pharmaceutical Society of Great Britain of the British Pharmaceutical Codex, in which the characters of and tests for the purity of many nonofficial drugs and preparations are given as well as the character of many glandular preparations and antitoxins that have come into use in medicine, but have not yet been introduced into the Pharmacopoeia. This work may also possibly serve as a standard under the Adulteration of Food and Drugs Act for the purity and strength of drugs not included in the Pharmacopoeia and as a standard for the commercial grade of purity of those in the Pharmacopoeia which are used for non-medical purposes.

Another legal difficulty connected with modern pharmacopoeias is the inclusion in some of them of synthetic chemical remedies, the processes for preparing which have been patented, whilst the substances are sold under trade-mark names such as verona. The scientific chemical name is often long and unwieldy, and the physician prefers when writing a prescription to use the shorter name under which it is sold by the patentees. In this case the pharmacist is compelled to use the more expensive patented article and the patient complains of the price. If he uses the same article under its pharmacopoeial name when the patented article is prescribed s/he lays oneself open to prosecution by, the patentee for infringement of patent rights. The only plan, therefore, is for the physician to use the chemical name (which cannot be patented) as given in the Pharmacopoeia, or for those synthetic remedies not included in the Pharmacopoeia, to use the scientific and chemical name given in the British Pharmaceutical Codex.