224 MATERIA MEDIC A AND THERAPEUTICS. 



geal cough. Tragacanth is partly converted into sugar by the 

 stomach; in large quantities it causes indigestion. It is 

 chiefly employed to suspend resins and heavy powders, such 

 as bismuth, the simple gum being preferable to the compound 

 powder, because not fermentable. 



2. ACTION ON THE BLOOD, SPECIFIC AND REMOTE LOCAL ACTION. 



Tragacanth, like other gums, enters the blood and tissues, 

 partly unchanged, partly as sugar and other products, and has 

 a nutritive effect of comparatively low value. It is not used 

 for this purpose. A remote demulcent effect on the urinary 

 organs is probably imaginary only. 



Olycyrrhizse Radix LIQUORICE BOOT. The 

 root or underground stem, fresh and dried, of Gly- 

 cyrrhiza glabra. Cultivated in England. 



Characters* In long cylindrical branched pieces, an inch 

 or less in diameter, tough and pliable ; of a greyish-brown 

 colour externally, yellow internally ; without odour, of a sweet 

 mucilaginous and slightly acrid taste. Digested with water, it 

 yields a solution which gives a precipitate with diluted sul- 

 phuric acid. 



Substances resembling Liquorice Eoot: Pyrethruin and Tarax- 

 acum, which are not sweet. 



Composition. Liquorice root contains grape-sugar, gly- 

 cyrrhizin, starch, resin, asparagin, and malic acid. Glycyrrhizin 

 is a yellow amorphous glucoside, C 24 H3 6 9 , with a strong bitter- 

 sweet taste and acid reaction, yielding glucose and a very bitter 

 substance, glycyrretin. 



Preparations. 



1. Extraction Glycyrrhizse. Aqueous. Dose, to 1 dr. 



2. Extractum Glycyrrhiza? Liquidum. Made as above with 



spirit. 2 fl. oz. = 1 oz. of solid extract. Dose, 1 fl. dr. 



3. Pulvis Glvcvrrhizae Compositus. 1, with 1 of Senna and 3 



of Sugar. Dose, 30 to 60 gr. 



Non-officinal Preparation. 



Pulvis Litmiritise Compositus (Ph. Germ, and Euss.). 1, 

 with 1 of Senna, of Sulphur, \ of Fennel, and 3 of Sugar. 

 Dose, a tea spoonful. 



Liquorice or its preparations are contained in many prepara- 

 tions throughouc the Pharmacopoeia. It especially covers the 

 taste of senna, chloride of ammonium, senega, hyoscyamus, 

 turpentine, and bitter sulphates. The powdered root is a useful 

 basis for pills. 



