50 GENERAL ACTIONS OP DRUGS 



If exudation is excessive, then drugs lessening secretion 

 are indicated. When tbe disorder is persistent, agents alter- 

 ing and improving the nutrition of the bronchial mucous 

 membrane are beneficial. Bronchitis accompanied by a 

 copious foul secretion is treated with volatile oils, which 

 exert an antiseptic action on the air passages. Expectorants 

 are usually administered with other agents influencing the 

 respiratory tract; e.^., drugs relieving cough and spasm and 

 those stimulating the respiratory movements or circulation. 



Drugs Stimulating the Eespiratory Centres. 



strychnine Stramonium 



Atropine .4Lmmonium carbonate 



Belladonna Strong ammonia 



Hyoscyamus 



External counter-irritation and heat. 



Drugs Depressing the Eesriratgry Centres. 



Many drugs depress and paralyze the respiratory centres 

 in large doses, but they are seldom used medicinally for 

 this purpose. 



Uses. — Drugs stimulating the respiratory centres and 

 movements are of great value in diseases of the chest — 

 especially bronchitis — attended with obstruction in the air 

 passages and cyanosis. They promote coughing and efforts 

 at expulsion of secretion and facilitate the entrance of 

 oxygen into the blood. Some, possibly ammonia, stimulate 

 the movements of the cilise lining the tracheal mucous 

 membrane. 



Strychnine is, perhaps, the most powerful respiratory 

 stimulant ; atropine is indicated where exudation is abundant, 

 while ammonium carbonate is prescribed to increase secre- 

 tion. 



Drugs Relaxing Spasm of the Bronchial Muscular 

 Tunic and Relieving Cough. 



External counter-irritation and heat. 



