16 GENERAL ACTION OF DRUGS 



and indirectly or reflexly stimulating the nervous mechan- 

 ism controlling secretion. As examples of this class, may be 

 mentioned alkalies, acids, emetics, and other agents stimu- 

 lating the mucous membrane of the mouth and stomach. 

 3rd, Mixed sialogogves, acting both specifically and reflexly. 

 Physostigmine, nicotine or tobacco and mercury prepara- 

 tions may be included in this category. 



Antisialogogiies. — These drugs may act in various ways to 

 lessen salivary secretion, but atropine is most notable in this 

 regard. It acts by depressing the peripheral endings of the 

 secretory nerves. 



Uses. — Sialogogues are not of much therapeutic value. 

 Some are added to the drinking water given to animals suf- 

 fering from fever, to relieve dryness of the mouth and thirst. 

 They are then called refrigerants; as, for example, potas- 

 sium nitrate, diluted phosphoric and other acids. The 

 reflex sialogogues are sometimes employed to stimulate the 

 mucous membrane of the pharynx in sore throat and relaxed 

 conditions ; as, for example, potassium chlorate in electuary 

 for horses. 



Excessive salivation produced by mercury salts or pilo- 

 carpine is relieved by an antisialogogue, i.e., atropine. 



Stomachics are drugs which, in therapeutic doses, mildly 

 stimulate the mucous membrane of the mouth and stomach, 

 thereby increasing the secretions and vascularity of these 

 parts, the appetite, and, in a less degree, gastric peristalsis. 

 These agents also influence the intestines, but this eff'ect will 

 be considered under carminatives. 



Stomachics may be divided into bitters, aromatics (drugs 

 containing a volatile oil and often very pungent), and aro- 

 matic bitters (drugs containing a volatile oil and a bit- 

 ter principle). While both the bitters and aromatics en- 

 hance the appetite, the action of the latter is more powerful 

 and fleeting. Very large doses of stomachics are distinctly 

 irritating, and cause anorexia, nausea, and vomiting in 

 animals capable of the act. 



