The following are leading questions on this subject and prescriptions in illustration:

To what extent is the dispenser justified in effecting the solution or suspension of an ingredient in a mixture which, though prescribed in an insoluble state, should be given in accurately divided doses?

To what extent do pharmacists consider it justifiable to manipulate a prescription in order to produce a good pharmaceutical preparation?

The following opinions of leading pharmacists in different parts of the United Kingdom were elicited in 1905 (C. & D. lxvi. 865, 901, and 936):

Messrs. Squire & Sons: 'It is not our practice to add mucilage to bismuth mixtures unless ordered in the prescription.'

Messrs. John Bell & Co.:'We do not think it permissible to "manipulate" a prescription without previously consulting the prescriber, except where the patient could not get an exact dose or which would have dangerous effects.'

Mr. T. Maltby Clague: 'Many have a preference for bismuth mixtures without suspending agents. To add these is an indiscreet liberty quite different from the departure which must sometimes be made to avoid a chemical change or an impracticable admixture.'

Messrs. Clay & Abraham: 'There would be no occasion to add mucilage to bismuth-carbonate mixture unless in exceptional circumstances. The addition is in many cases a distinct disadvantage. Many medicines are prescribed which it is impossible to dispense as written.'

Messrs. Jolly & Co.: 'A general rule with us is not to add anything to a mixture unless absolutely necessary- \in which case a note is made on the prescription showing the quantity and composition of the agent employed.'

Mr. Harold E. Matthews: 'A pharmacist should never alter the medicaments in a prescription nor the quantities on his own responsibility. He should exercise his discretion as to addition or omission or excipients.'

Mr. Stewart Hardwick: 'Any deviation considered necessary should not be made recklessly, but with the governing idea in mind- viz., " the intention of the prescriber." '

Mr. Peter Boa:' The principle which guides a pharmacist is to make no addition if the prescription can be dispensed as it stands, and if any addition is to be made it must be of the most innocent description, and only with the object of securing equality of dosage or preventing serious deterioration of the active principle.'

Dr. J. F. Tocher: 'The addition of mucilage or of any substance changing the character of the dispensed article is quite unwarrantable, without the consent of the medical practitioner.'

Mr. E. Saville Peck:'The one aim of the pharmacist should be the faithful interpretation and subsequent carrying out of the actual intentions of the prescriber in so far as they can be ascertained from a prescription. . . . He is not justified in "manipulating" a prescription in order merely to produce a good pharmaceutical preparation.'

Mr. W. F. Wells: 'If there is an apparent error in a prescription, it is the dispenser's duty to communicate with the prescriber. In the case of the bismuth mixture, the chemist had no right to add mucilage, as it is not necessary, and many prescribers prefer the mixture without.'

Mr. Harold Wyatt: 'The standpoint I take with regard to alterations is- (1) Never add to a formula anything of an active nature; (2) always note additions on the prescription; (3) never make an alteration or addition out of mere routine; (4) always have a good and logical reason to give the doctor for such additions.'

Another case may be cited. Is the substitution of liq. arsenici hydrochlor. justifiable in the following prescription?-

The potassium carbonate in the liquor arsenicalis precipitates the mercury, and there is a possibility of the patient getting the whole of it (as mercuric hydroxide) in the last dose.

An analogous result is shown in mixtures of liq. arsenicalis and liq. strychninae in certain proportions, the alkaloid being in this instance precipitated. In both these cases the acid solution should, preferably, be used.

A prescriber gave a patient the following prescription, which was dispensed with liquor arsenicalis, and in due course the patient died, the symptoms being those of strychnine poisoning (the alkaloid separated in crystals):

Such prescriptions are very dangerous, as they often 'go all right'in dispensing, being quite clear when sent out, because the precipitation of the alkaloid is delayed. The following are the solubilities of the specified alkaloids in water at 150 to 200 C.:

The solubilities are greater in aqueous alkaline solution- e.g., of strychnine 1 in 3,000 of 10-per-cent. ammonia solution- but ammoniated alcohol is a poorer solvent of alkaloids than alcohol itself. From the above data dispensers will be able to judge whether or not precipitation is likely to take place in simple mixtures of alkaloidal salt solutions and alkalies (C. & D. 1912, 11. 475). See also page 291.