00 
Dose. — ‘‘Average dose; O.050 Qni. — 050 milligTammes (d grains).'' 
(U. S. P.) 
•‘Should be kept in veil stoppered bottles, protected from heat and 
light.'’ 
ANTI PYRIN A. 
Antipyriue. 
Official in the Austrian and Swiss Pharmacopoeias as Antipyrinum; 
now official in the German Pharmacopoeia as Pyrazolonum phenvldi- 
methylicum (formerly as Antipyrinum); in the British as Phenazonum, 
and in the French as Analgesine. Other names that have been applied 
to it are anodyiiin, metozin, o:oydiriiethylcliinizin^ parodyn^ y^henazon^ 
phenylo7u sedatin. 
Chemistry. — Chemically it is phenyldimethylisopyrazolon; its deri- 
vation may be seen from the following formulas: 
HC— CH 
HC— CH 
II II 
N CH 
HC— CH, 
II 1 
N CH. 
II II 
HC CH 
\/ 
\ 
\/ 
V 
Y ■ 
H 
H 
H 
Pyrrol 
Pyrazol 
Pyrazolin 
HC-CH, 
II 
N CO 
HC=CH 
CH,C=CH 
HN CO 
CII3X CO 
\/ 
X 
\/ 
\ 
\/ 
\ 
H 
H 
QH, 
Pyrazolon 
Iso-pyrazolon 
Dimethyl-phenyl- 
iso-pyrazolon 
It is not obtained directly from the mother substance isopyrazolon, 
but is built up synthetically by condensation of phenylhvdrazine with 
acetoacetic ether, and methylation of the product. 
Character. — *‘A colorless, almost odorless, crystalline powder, or 
tabular crystals, with a slightlv bitter taste." 
Solubility. — Soluble in less than 1 part of water, and in 1 part of 
alcohol. 
Purity. — “Two Cc. of an acpieous solution of Antipyrine (1 in 100) 
mixed with an equal volume of nitric acid assumes a yellowish color, 
passing to crimson on warming (distinction from acetanilide and 
acetphenetidinj.'’ 
“On warming 0.1 Gm. of Antipyrine with sodium hydroxide T. S. 
[Liq. Sodii Hydroxidi] and again warming after the addition of chloro- 
form, the disagreeable odor of phenyl-isocyanide should not be 
developed (absence of acetanilide)." 
