32 GENERAL ACTIONS OF DRUGS 



each to a pint. Linseed oil or cottonseed oil are also mixed 

 with water. Epsom salts are still more efficacious (H.ibii. 

 to gallon of water. (D. 5 i.-iv. to pint); while oil of turpentine 

 (H. 3 ii.-iv.; D. 3 i.-iv.) is very active and especially useful in 

 colic and flatulence, mixed with the enema. When clysters 

 are given to be absorbed they should always be deeply 

 injected in quantities of one-half to one gallon for horses ; 

 or one-half to one pint for dogs. In chronic constipation 

 and torpidity of the bowels plain cold water (55°-60° F.) 

 injections are indicated. 



Medicated irrigations are most serviceable in catarrhal 

 disorders of the bowels (dysentery, etc.), i.e., the fluid is 

 allowed to flow in and out again till the solution returns 

 clear. 



Drugs Acting on the Circulation. 

 I. — Acting Upon the Blood. 



(a) Blood Plasma. — The alkalinity of the blood serum 

 can be increased by the use of the salts of the alkaline and 

 earth metals ; i.e., potassium, sodium, lithium, ammonium, 

 magnesium and calcium compounds. This effect is of value 

 therapeutically in rheumatism, hsemoglobinsemia and uric- 

 acidaemia. In the latter condition the antacids — especially 

 potassium and lithium salts — dissolve uric acid, convert it 

 into urates, alkalize the urine and increase its secretion. 

 Drugs which remove considerable fluid from the body, as 

 purgatives, diaphoretics and diuretics, necessarily alter the 

 composition of the blood serum. By removing fluid from 

 the plasma, these agents are useful in aiding absorption of 

 inflammatory exudations, dropsies and oedemas, since the 

 mass of fluid removed is soon replaced from that contained 

 in the food and tissues. In the various infectious and con- 

 stitutional diseases treatment is largely directed to exciting 

 the secretions and excretions with the purpose of eliminating 

 products of tissue waste and bacterial action from the blood, 



