648 CHRYSAROBIN 



tanning and shrivelling carcinomatous growths. Jarisch's 

 ointment for psoriasis consists of 60 grains pyrogallic acid 

 to 1 ounce of lard. 



Tannalbin, a dried albuminate of tannin, has been much 

 used in the treatment of diarrhoea and dysentery in young 

 animals. It is a light brownish powder, without odour 

 or taste, insoluble in water and unaffected by the gastric 

 juice. In the intestine it is slowly dissolved, exerting an 

 astringent-disinfectant action on the mucous membrane. 

 It contains about 50 per cent, of tannin. Doses, horses 

 and cattle, 3J- to ^iv. ; foals and calves, grs. xx. to grs. xl. ; 

 three times daily, in gruel, milk, or electuary. Tanni- 

 gen (di-acetyl-tannin), prepared by the action of acetic 

 anhydride on tannin, dissolved in glacial acetic acid, is a 

 yellowish-grey powder, odourless and tasteless, insoluble 

 in water, freely soluble in alcohol. It passes through the 

 stomach unchanged and acts as an intestinal astringent. 

 Recommended as a remedy for parasitic intestinal catarrh 

 in foals. Doses, grs. xx. to 3J-> i n boiled milk or linseed 

 tea. 



CHRYSAROBIN 



ARAKOBA. Crude Chrysarobin. Goa powder. A substance 

 found in cavities in the trunk of Andira araroba, dried 

 and powdered, and imported from Brazil. Nat. Ord. 

 Leguminosae (B.P.). 



Chrysarobin, obtained from Araroba by extracting with 

 hot chloroform, evaporating and powdering, occurs as a 

 crystalline, brownish-yellow powder, insoluble in water, 

 but soluble in chloroform, and slightly soluble in alcohol. 

 By oxidation it yields chrysophanie acid, C 10 H 8 3 , which is 

 a constituent of rhubarb, stains yellow, and is less irritant 

 than chrysarobin. 



Both chrysarobin and chrysophanie acid are irritant and 

 parasiticide, are seldom given internally, but are applied, 

 usually in the form of a 2 to 5 per cent, ointment, in the 

 second squamous stages of eczema, and in psoriasis and 

 ringworm. Given by the mouth, they are gastro-intestinal 



