CHAPTEE XIII 

 DRUGS ACTING UPON THE RESPIRATORY SYSTEM 



Respiratory Stimulants are agents which quicken or deepen 

 the respirations through stimulation of the respiratory center. This 

 stimulation may be produced by : 



1. Reflex stimulation of the peripheral nerves. (Vapor of am- 

 monia stimulates the nasal branch of the fifth nerve when inhaled 

 and reflexly stimulates the peripheral nerves.) Cold douches act 

 in a similar manner. Artificial respiration besides bringing air in 

 contact with the blood in the lungs also serves this purpose. 



2. Direct stimulation of the center through an increase of tem- 

 perature or venosity of the blood. (External heat, venous blood). 



3. Direct through drugs. 



Ammonia Cocaine 



Strychnine Atropine 



Caffeine 



Indications. These drugs are of service as respiratory stimu- 

 lants particularly in pulmonary diseases associated with dyspnoea, 

 as pneumonia, severe bronchitis, emphysema, lowered activity of 

 the respiratory center, exhausting diseases, fatigue and in depres- 

 sion by narcotics. 



Ammonia. Ammonia is very serviceable as a quickly acting 



cardiac and respiratory stimulant in syncope, collapse and other 



sudden heart failures. It is usually given by inhalation but may 



. be administered intravenously in the proportion of one part of 



stronger ammonia water to four parts of water. 



Strychnine. This drug has a rapid and powerful action with 

 but little danger of undesired effects, but its period of action is rela- 

 tively short. It is particularly useful in pneumonia and other de- 

 bilitating diseases, to tide over a period of depression Some au- 

 thorities do not recommend it for continuous use, while others ad- 

 vise it throughout the course of serious diseases. , ^ -.i. 



Caffeine. This drug acts more slowly than strychnme but witn 

 a more persistent action. General indications for caffeine are given 



in another place. i t i^i i -j. 



Atropine. The action of this drug is not marked although it 

 paralyzes the bronchial muscles, dries up secretions of the bronchi, 

 and is of particular benefit in asthmatic conditions. Atropine is 

 also of considerable service in the second stage of acute diseases of 



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