1 6 4 MATERIA MEDIC A AND THERAPEUTICS. 



meg-rim or sick'- headache, due to similar spasm in the 

 trigeminal area, are also benefited hy this drug. 



The reflex irritability of the cord is reduced (in animals) 

 by nitrite of amyl, which has therefore been proposed as a 

 remedy in poisoning by strychnia. Neither the peripheral 

 nerves nor the muscles are aif ected when it is given through the 

 blood. Respiration is disturbed, apparently by the alteration 

 of the haemoglobin and circulation, not through the nervous 

 system. The nitrite sometimes affords immediate relief in 

 asthma, but the dyspnoea may as quickly return. The body 

 temperature falls, from obvious causes. 



4. REMOTE LOCAL ACTIOX. 



Nitrite of amyl probably escapes from the body by the 

 urine, which is decidedly increased in amount, and may contain 

 sugar. Both of these effects are probably results of local 

 disturbance of the pressure in the kidneys and liver re- 

 spectively. 



NITRO-GLYCEEJNUM. NITROGLYCERINE. 

 CaHsNaOg. (Not Officinal) 



Source. Made by dropping Glycerine into a mixture of 

 Sulphuric and Nitric Acids, washing, and evaporating to a 

 proper density. 



Characters. An oily liquid, colourless, odourless, with a 

 sweet pungent taste. Specific gravity, 1'60. Slightly soluble in 

 water ; freely in fats, oil, alcohol, and ether. Highly explosive, 

 and, when mixed with infusorial earth, constitutes dynamite. 

 Never used in the pure state. 



Preparation. 



Liquor Nitroglycerine., 1 gr. in 100 min. of rectified spirit. 

 Dose, $ to 2 min. ; in water, or as a chocolate tablet. 



ACTION AND USES. 



This powerful substance closely resembles in its action the 

 nitrites of amyl and soda ; its activity being apparently due to 

 nitrous acid formed by its decomposition within the body. It 

 is used for the same class of cases, such as angina pectoris, 

 chronic heart disease, sea-sickness, and asthma and other spas- 

 modic disorders. 



