The British Pharmacopoeia and its critics / by Professor Attfield.

  • Attfield, John, 1835-1911.
Date:
1885
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Licence: Public Domain Mark

Credit: The British Pharmacopoeia and its critics / by Professor Attfield. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    remove all atropine. He does not offer proof that the matter which he says is lost is of any value. Extractum Cascara Sagrada and Extractum Cascara Sagrada Liquidum.—Why exhaust the former with dilute spirit and the latter with water? ask Conroy ar.d Burd, and Martindale echoes the inquiry. The usual precedents have been followed and with care and skill the products are satisfactory, but original investigation is needed here. Expe- rience will guide as to which of the two modes of working is the better. Extractum Cinchonce Liquidum.—The criticisms of pharmacists on this preparation vary as much as the raw material of the article varies. Perhaps the one variation is not altogether unconnected with the other. Millhouse and Cracknell are opposed respecting the miscibility writh water of the samples they have prepared. Conroy raises quite a series of objections, while A. E. Robinson says “ it leaves little to be desired as representing a thoroughly reliable and stable preparation of cinchona.” Umney leaves 40 per cent, of alkaloids in the bark he operates on, Moss and Gravill only 15 per cent. Howard says that “ in some cases ” half may be left. Tot capita, tot sensus. Referring to the assay of this extract, Maben says of fluid grains “ whatever that may mean.” Mar- tindale echoes “ whatever that may mean.” These gentlemen are referred to what is stated in the pre- face respecting “ fluid parts” signifying “ the volume of an equal number of parts of water,” and to the appendix respecting what is stated of “ the grain measure being the volume of a grain of distilled water,” and if they cannot draw the not very seriously subtle inference, the next Pharmacopoeia will probably render such an effort superfluous. W. N. Allen wanders to the sixth place of decimals to find the fluid grain; but his calculations are founded only on an official approximate statement of the strength of Liquor Morpliina Hydrochloratis. Extractum Ergota Liquidum.—Ward would not have decreased the proportion of spirit used. Conroy and A. E. Robinson commend the decrease. Umney and Moss would have used still less spirit. Extractum Gelscmii A leoholicum. — Conroy and Perry say of this w hat they said of Extractum Bella- donna Alcoholicum, which see. Extractum Glycyrrhiza Liquidum.—Conroy ap- proves of the increase of spirit from one-eighth to one-sixth, but would have added as much as one- fourth, to prevent fermentation in summer. Tern- pus omnia revelat. Extractum Jahorandi.—Perry repeats his criti- cism. Vide ante, Extractum Belladonna Alco- holicum. Extractum Nucis Vomica —Martin savs this will vary in moistness, becoming too strong as it dries, and that the only remedy is to dry and powder and standardize the product. Botham repeats. Could not pharmaci-ts ado] t another remedy, not altogether unfamiliar to them in dealing with soft extracts, and use—an excipient? Gravill says the addition of milk sugar gives a presentable product. Conroy says— exhaustion good, product superior to old, standard- izing satisfactory, test trustworthy. Extractum Opii.—Umney, supported by Moss, says that “ opium in powder ” as oidered commonly yields much over the 50 per cent, of product directed to be obtained, and makes the useful suggestion that the words “ in powder” be omitted—which has been accepted. The direction that “this extract shoul 1 yield about 2(> per cent, of morphine,” which is the important new feature, still, of course, holds good. Extractum Pareira Liquidum. — Umney would make this not from the extract as ordered, but direct from the root. But Proctor long ago showed that pareira root varied much in yield of extract, and that therefore the strength of a given bulk of liquid extract piepared direct from a given weight of root would rarely be twice alike. Hence the present process. Conroy approves of the process, stating that in his experience the root may yield about three times as much extract at one time as at another, that is, from 26 down to 9 per cent. Moss, also, disagrees with Umney. Umney says the present liquid extract is about three times stronger than the old. Not necessarily ; the old might have been the same strength and might have been weaker. From Conroy’s data 16 fluid ounces of the old might have contained as much as 4 ounces of extract or as litt’e as 1£. The present liquid extract will always contain 4 in 16. Extractum Rhamni Frangula.—Perry repeats his criticism (see Extractum Belladonna Alcoholicum), and Conroy repeats his (see Extractum Cascara Sagradce Liquidum). Extractum Sana Liquidum.—Conroy says of the process it “wdll probably yield a superior extract to the old form,” but Umney, while unable, he states, to guess whether it will be appreciated, because it is unlike anything previously in vogim, yet unhesi- tatingly says “the process is not a desirable one, and certainly, for the exhaustion of sarsaparilla, most wasteful.” Umney, wdiile properly, and more or less modestly, directing attention to his own opinions, and numerous valuable pharmaceutical notes and papers, seems in this case to have overlooked the labours and statements of Proctor, Stephenson, Duhamell, Smith, Husband and Barton. Extractum Taraxaci Liquidum.—Cracknell thinks the process of the American Pharmacopoeia supeiior. Umney approves of the newr British extract. Ferri et Amrnonii Citras, Ferrum Tartaratum.— The criticisms on these substances have been dealt with by Redwood. Ferri et Quinina Citras.—The valuable criticisms of Fletcher and Umney have resulted in the reduc- tion of the official requirements as regards strength in alkaloid from 16 to 15 per cent. Glycerinum Acidi Tannici.—Millhouse would add a little water to this preparation and to the glycerines of carbolic acid, gallic acid, and alum. Baxter points out that if water were added to the tannic preparation it might be spoilt for throat affections, being then rendered thin enough to run away from the parts. Some of the glycerines are made up with water to avoid inconvenient consistence, and for other special purposes. Otherwise dilution is left to the medical practitioner, who decides not only whether it be needless, useful, or indispensable, but to what extent it should be carried. Injectio Morphince Hypodermica.—Botham’s criti- cisms have been met by Farr, who rightly shows that loss of alkaloid in washings and filtrates requires the apparent excess of salt ordered in the formula, and says the same remark applies to the test. Bearing in mind the more correct formula now given for acetate of morphine it will be seen that the strength of the present injection, as shown by Gravill, does not greatly exceed that of the last