CHAPTER IX. 

 NOTES ON MAGISTRAL PHARMACY. 



To Magistral or Extemporaneous Pharmacy belongs the compounding 

 and dispensing of drugs. Its successful performance naturally has to be 

 preceded by a knowledge of their physical and chemical characters. Dex- 

 terity in the art can only be secured by long practice, something for which 

 the medical student has no opportunity. The dispenser stands between 

 the prescriber and the patient and only a very intimate acquaintance with 

 the characters and doses of medicines will enable him to successfully per- 

 form his duty to each. The physician who dispenses his own remedies 

 assumes a double liability in that he becomes sponsor for the proper se- 

 lection of the remedy as well as its preparation so that the patient may 

 take the prescribed quantity without danger to himself. 



Carelessness in weighing and measuring medicines should not be toler- 

 ated on any account. Guessing at the weight or volume of ingredients 

 is criminal. 



On the Dispensing of Mixtures. In this procedure as in every other 

 the dispenser must take the greatest care that all the apparatus used must 

 be scrupulously clean. The bottle selected must be of such capacity as to 

 be filled by the ingredients. Sick persons are often so full of fear and doubt 

 that the slightest unusual feature, -insufficient bulk, change in colour, 

 flavour or clearness of a mixture, at once awakens suspicion. 



If the prescription presents no incompatibles and the dispenser knows 

 that it will be and remain clear when filled, it may be dispensed directly 

 into the bottle. Or if it is intended that a precipitate is to be produced, the 

 same procedure may usually be followed. It is a good rule to introduce 

 all fluids through a funnel as this serves to keep the neck and sides of the 

 bottle clean and dry. Solutions of common salts and any other solution 

 that is not quite as clear as it ought to be should always be passed through 

 a filter; a little absorbent cotton in the neck of the funnel often serves very 

 well. The fluids of least bulk should as a rule be first dispensed unless 

 there is some special reason for deviating from this, for example very vo- 

 latile fluids should be dispensed last. 



Separate the soluble solids and dissolve them in a portion of the men- 

 struum by trituration in a mortar before placing them in the bottle. Never 

 permit solids that are completely soluble in the vehicle to leave the dis- 

 pensary undissolved. The method of adding soluble salts directly to the 

 mixture while it may save some time is not to be commended because of 



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