INTRODUCTION". 17 



pressed conditions of the cardiac apparatus. The 

 most rapid and energetic of this class are ether, alco- 

 hol, ammonia, and the application of heat. 



Cardiac Tonics stimulate the cardiac muscle, 

 slowing and lengthening the contractions if given in 

 moderate doses; but in large doses produce irregu- 

 larity of the heart's action and may cause death by 

 syncope if toxic doses have been given. The most 

 powerful of this class is digitalis, then convallaria, 

 and strophanthus. Also caffeine and strychnine. 



Cardiac Sedatives decrease both force and fre- 

 quency of the heart's action, and are used to control 

 palpitation and over-action of that organ. The chief 

 members of this class are aconite, veratrum viride, 

 and digitalis. 



Vascular Stimulants dilate the peripheral ves- 

 sels and increase the peripheral circulation; this 

 equalizes blood pressure and so prevents and relieves 

 internal congestions — as alcohol, ether, nitrites, ni- 

 trous ether, liquor ammonii acetatis, and heat ap- 

 plied locally by poultices. 



Vascular Tonics and Sedatives increase the 

 contractile power of the arterioles, which decreases 

 the capillary circulation and raises blood pressure — as 

 ergot, digitalis, opium in small doses, and cold ap- 

 plied locally. 



Agents Acting on the Digestive Apparatus. 



SiALOGOGUES are agents w^hich promote the secre- 

 tion and flow of saliva — as ether, chloroform, mus- 

 2 



