PHYSOSTIGMINE SALICYLATE 389 



The official preparations are the fluid extract and tinc- 

 ture of physostigma, but physostigmine is solely used in 

 veterinary medicine, since it is more certain and generally 

 free from calabarine, which produces, in toxic doses, a 

 tetanic condition followed by paralysis. 



Physostigmine Salicylas. Physostigmine Salicylate. 

 C,,H,,N30AHeO, (U.S. P.) 



Synonym. — Eserine salicylate. The salicylate of an 

 alkaloid obtained from physostigma. 



Derivation. — Physostigmine is obtained from the alco- 

 holic extract of Calabar bean by dissolving the extract in 

 water, adding sodium bicarbonate, shaking the mixture with 

 ether, and evaporating the ethereal liquid. The salicylate 

 of the alkaloid — the most stable salt — is made by adding 

 physostigmine to a solution of salicylic acid in boiling 

 distilled water, when the salt crystallizes on cooling. 



Properties. — Colorless, or faintly-yellowish, shining, aci- 

 cular, or short, columnar crystals; odorless, and having a 

 bitter taste. Soluble in 150 parts of water, and in 12 parts 

 of alcohol ; in 30 parts of boiling water, and very soluble in 

 boiling alcohol. (U. S. P.) 



Dose.—n., gr.i.-i.ss. (.06-.09); C, gr.i.-iii. (.06-.18); D., 

 gr.rk-yV (.0006-.002). 



Given usually intratracheally or subcutaneously to 

 horses. 



Physostigmine Sulphas. Physostigmine Sulphate. 

 U. S. P.) 



Synonym. — Eserine sulphate. 



The sulphate of an alkaloid obtained from physostigma. 



Properties. — A white, or yellowish-white, micro-crystal- 

 line powder, odorless, and having a bitter taste. It is vei^y 

 deliquescent when exposed to moist air, and gradually turns 

 ^reddish by exposure to air and light. Very soluble in water 

 and in alcohol. 



