AMMONIA PREPARATIONS 119 



death may take place instantaneously from edema and spasm of the glot- 

 tis. Otherwise, more or less extensive inflammation of the alimentary 

 canal will follow, according to the amount ingested. Diluted vinegar 

 and lemon juice, together with the white of egg, or sweet oil, should be 

 given as antidotes. Tracheotomy may be indicated, if there is glottic 

 obstruction. Ammonia, in passing through the mouth, throat, gullet and 

 stomach, reflexly stimulates the heart and respiration before absorption 

 can occur. 



Ammonia is an antacid in the stomach, but should not be employed 

 in gastric irritability. 



Respiratory Tract. — Inhalation of stronger ammonia through the 

 nostrils causes reflex stimulation of the heart and respiration by irritation 

 of the nasal branches of the fifth nerve. Care must be exercised to pre- 

 vent inflammation of the air passages. Ammonia stimulates the respira- 

 tory centre when it is injected into the blood. Given under the skin in 

 lethal doses, ammonia causes death by paralysis of the respiratory 

 centres. 



Circulation,. — It is probable that ammonia only acts reflexly to stimu- 

 late the heart through irritation of the stomach when it is ingested. If 

 given, intravenously or subcutaneously, ammonia stimulates directly the 

 heart muscle, and probably the accelerator and vasomotor centres, mak- 

 ing the cardiac pulsations stronger and quicker and increasing vascular 

 tension. Earely the vagus centre is stimulated and the heart's action 

 slowed. Lethal doses paralyze the cardiac muscle. Ammonia differs 

 from alcohol in being more evanescent as a stimulant, in not affecting the 

 brain nor metabolism, and in not acting as a food. 



Blood. — The normal blood contains ammonia, which is supposed to 

 aid in maintaining its fluidity. The action on the blood is unknown. 

 Ammonia is thought to prevent coagulation of blood within the vessels , 

 in conditions favorable to thrombosis. 



Nervous System. — ^An intravenous injection of a lethal dose of ammo- 

 nia occasions tetanic convulsions in animals, owing to stimulation of the 

 reflex and motor functions of the cord. Medicinal doses excite the spinal 

 reflex and motor centres. When ammonia is applied directly to nerve 

 tissue it excites in dilute solution, but paralyzes functional activity in 

 concentration. The brain is unaffected by the therapeutic administration 

 of ammonia. 



Elimination. — Ammonia combines with acid in the stomach and is 

 absorbed into the blood. Ammonia and its carbonate' are acted upon by 

 the liver and there transformed into urea, in which form ammonia com- 

 pounds escape in the urine. Urea being the most active diuretic there is 

 some augmented flow. The urine is, however, not alkalized as by the 

 salts of the other alk^ine metals. 



Summary. — Heart and respiratory stimulant and antacid. Exter- 

 nally, rubefacient, vesicant, and escharotic. 



Uses. — The indications for ammonia are closely in accord with its 

 physiological actions. 



Externally. — It is frequently used in stimulating liniments. One 



Digitized by Microsoft® 



