MATERIA MEDICA 



Definition. Materia Medica or Pharmacognosy, for the terms 

 as used by pharmacists are synonymous, may be defined as that 

 science which aims at a complete and systematic knowledge of crude 

 drugs of animal or vegetable origin. The term drugs may be under- 

 stood to include all parts of animals or vegetables used in medicine, 

 or such of their products as have not undergone any material 

 elaboration or separation into their constituents ; it is, however, 

 not susceptible of exact limitation, and hence substances may be 

 included which are of dietetic or technical rather than medicinal use. 



A complete knowledge of a drug must include a knowledge of 

 the morphological nature and the structure, both macroscopic and 

 microscopic, of such as are organised, of the botanical or zoological 

 source, of the constituents both active and inactive, their nature, 

 the amounts in which they are present, and the relation they bear 

 to the constituents of other drugs. The geographical source, the 

 cultivation, mode of collection, preparation for the market, the trade 

 route, commercial varieties, history, uses, &c., must also be known. 

 To attain this knowledge the aid of chemistry and of chemical methods 

 of investigation, of botany and botanical methods, of physiology, 

 geography, commerce, history, &c., must be sought, or at least the 

 results of other investigators in these respects utilised, and the infor- 

 mation thus obtained combined to form a complete knowledge of 

 each drug, and these systematised to build up the science of 

 pharmacognosy. 



Pharmacognosy may be subdivided into Scientific Pharmacognosy, 

 as above described, and Applied Pharmacognosy. Applied Phar- 

 macognosy is the application of scientific pharmacognosy to the 

 solution of the pharmacognostical problems that are constantly 

 arising in the daily work of the pharmacist. Thus Scientific Phar- 

 macognosy includes an intimate knowledge of the structure of 

 vegetable drugs ; Applied Pharmacognosy utilises this knowledge 

 to identify the drug entire or in powder and to determine its 

 purity. Scientific Pharmacognosy treats of the constituents of 



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