FLUIDEXTRACTS 31 



MENSTKUUM PEEPAEATION 



Glycerin 250 mils, Alcohol Tinctura Lactucarii 

 500 mils, Water 250 mils 



Glycerine 100 mils. Alcohol Tinctura Ehei 

 500 mils, Water 400 mils Tinctura Ehei Aromatica 

 Hydrochloric acid 10 mils. Al- 

 cohol 600 mils, Water 400 mils Tinctura Sanguinarias 

 Aromatic Spirits of Ammonia Tinctura Valeriana; Ammoniata 



FLUIDEXTRACTA — FLUIDEXTRACTS 



Fluidextracts are concentrated liquid preparations of vegetable 

 drugs, containing alcohol either as a solvent or preservative and 

 bearing a uniform relation to the drug used so that one mil of the 

 iluidextract closely represents the activity of one gram of the air 

 dried powdered drug of standard quality. They possess the follovsr- 

 ing advantages over tinctures: 1. They have a definite strength, 

 representing 100 per cent, of the activity of the crude drug, conse- 

 quently the dose is the same as for the crude drug and need not be es- 

 pecially remembered. 2. They are so concentrated that less is re- 

 qiiired for action, and 3. They keep better than tinctures and some 

 improve -with age. 



With few exceptions, the fluidextracts of the Pharmacopcsia may 

 be classified according to the menstrua used in the extraction of the 

 drugs and the process of manufacture employed, but there are several 

 drugs which require special manipulation to make satisfactory prep- 

 arations and for them definite formulas have been devised and are 

 printed in full in the text. The formulas for the other fluidextracts 

 correspond to one of the following types : 



Type Process A. In this class are included those fluidextracts 

 that are made with a menstruum of alcohol or a mixture of alcohol 

 and water by the usual process of percolation. 



Type Process B. In this group are included those fluidextracts 

 in which glycerin or an acid is used in the extraction and two men- 

 strua are successively employed. The first menstruum contains the 

 acid or glycerin in definite proportion to the amount of drug while 

 the second consists of a mixture of alcohol and water intended for 

 completing the exhaustion of the drug. 



Type Process C. This is the process of fractional or divided 

 percolation (repercolation) . It is especially recommended for drugs 

 containing volatile ingredients, or constituents injured by heat, but 

 may be used as an alternative process in the formulas in which Type 

 Process A is directed. 



Type Process D. In this class are included those fluidextracts 

 in which extraction is effected by infusion and percolation with boil- 

 ing water, alcohol being added to the concentrated liquid as a pre- 

 servative. 



