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CITRATE OF CAFFEIN AS A REMEDY FOR HEADACHE. 
flammable. When thrown on burning coals, it expands in pur- 
ple vapors. It is not decomposed immediately by potassa, nor by 
nitric or sulphurous acids, but sulphuric acid decomposes it, and 
sets at liberty a part of the iodine. 
The action of the air discolors it slightly by liberating a little 
iodine, which may be readily removed by the alkalies and mercury, 
a globule of which thrown into the vial, is sufficient to retain the 
ether in a state proper for inhalation. Its density admits of its 
being kept under water, in which it is insoluble ; a circumstance 
favorable to the mode of using it suggested by Dr. Huette. 
ON CITRATE OF CAFFEIN AND ITS EMPLOYMENT AS A REMEDY 
FOR THE IDIOPATHIC HEADACHE, CALLED MIGRAINE. 
ByM. Hannon. 
Citrate of Caffein may be obtained by two processes, the most 
simple consists in infusing raw coffee, ground to powder, at the 
temperature of 176° Fahr. in a very weak solution of citric acid, 
filtering the liquid whilst yet hot, adding two thirds of its volume 
of ether, and agitating the mixture strongly to remove the chloro- 
genic acid from the watery solution. The latter is separated 
from the supernatant ether, and is carefully evaporated with a gentle 
heat. The Citrate of Caffein crystallizes in long needles, which 
when redissolved in distilled water and again evaporated, are ob- 
tained in beautiful long acicular white silky crystals in radiating 
groups. 
The second process consists in making the compound by the 
direct union of its constituents, the caffein being dissolved in a 
weak solution of citric acid at the temperature of 112° Fahr. and 
the solution gently evaporated till the citrate crystallizes. 
This salt is very soluble in water, and is assimilated much more 
readily than pure caffein when taken into the stomach. It con- 
sists of one equivalent of caffein, three equivalents of citric acid, 
uid two equivalents of water. 
Pills of Citrate of Caffein. 
Take of Citrate of Caffein, 8 grains. 
Chiendent, (Triticum repens) 15 " 
Mix, and divide into ten pills. 
