1 62 MATER i A MEDIC A AND THERAPEUTICS. 



neuralgia very quickly ; in some cases it fails. It has been 

 given in other forms of pain in the face, such as toothache 

 (locally) ; in neuralgia of the limbs ; and in painful menstrua- 

 tion. 



AMYL NITRIS. NITRITE OF AMYL. C 5 H n .N0 2 . 



Source. Produced by heating Nitric Acid with Amy lie 

 Alcohol, distilling, and purifying the product. 



Characters. An ethereal liquid, of a yellowish colour, and 

 peculiar pine-apple odour. Sp. gr., '877. Insoluble in water ; 

 soluble in rectified spirit, ether, and chloroform. 



Impurities. Nitric and hydrocyanic acids. 



Dose. 2 to 5 min., used with caution as inhalation from 

 a crushed capsule,; or ^ to 1 min. internally, dissolved in recti- 

 fied spirit. 



ACTION AND USES. 

 1. IMMEDIATE LOCAL ACTION AND USES. 



Applied directly to peripheral nerves and muscles, nitrite of 

 amyl depresses or paralyses them. It is never so employed in 

 man. Internally, the drug is seldom given by the mouth, 

 except in cholera. 



2. ACTION ON THE BLOOD. 



Nitrite of amyl is almost invariably administered by 

 inhalation, a few drops being kept ready for use in a glass 

 capsule (enveloped in cotton wool), which may be broken 

 between the fingers and thumb when required. The vapour 

 instantly enters the circulation through the lungs, converts a 

 certain amount of haemoglobin into methsemoglobin, and thus 

 interferes with the oxygenating function of the red corpuscles; 

 the amount of oxygen absorbed (in animals) being quickly 

 lowered, as well as the excretion of carbonic acid. The blood 

 of animals killed by nitrite of amyl is of a chocolate colour ; 

 but the effect of an ordinary inhalation in man is very 

 transitory. 



3. SPECIFIC ACTION AND USES. 



Nitrite of amyl almost instantaneously reaches the tissues, 

 and produces striking phenomena. Two to five drops, inhaled 

 as directed, immediately produce a sense of fulness and 

 throbbing in the head ; flushing of the face, neck, and trunk ; 

 tingling over the surface generally ; dilatation of the pupils, 

 and disturbance of vision; giddiness and unsteady gait; 



