DISEASES OF THE ORGANS OF CIRCULATION 71 



4. Plumbi acetas. Lead acetate. A good haemostatic in 

 gastric hemorrhage. Used empirically in hemorrhage from the 

 lungs, kidneys, bladder and uterus. Dose for horses, 2-10, 5ss to 

 ijss; cattle, 1-5, grs. xv to 5i; dogs, 0.05-0.2, grs. 34 to iij. 



5. Alumen. Alum. A styptic in intestinal hemorrhage. 

 Dose for horses and cattle, 10-25, 5 ijss to vj; dogs, 0.5-2, grs. 

 vij to XXX. 



6. Liquor ferri chloridi. Solution of chloride of iron. Exter- 

 nal styptic, undiluted, or with collodion 1 : 10, upon wounds; 1 to 5 

 per cent, solution in water on mucous membranes; in J^ per cent, 

 solution by inhalation in hemorrhage from the lungs. Internally, 

 in gastric hemorrhage, freely diluted. 



7. *Creolin. External styptic in operations in 3 per cent, solution. 



2. VASOMOTOR STIMULANTS. DRUGS THAT CONTRACT 

 BLOOD-VESSELS 



Synonyms: Angiosthenics, vaso-astringents, vaso-constringents. 



Actions. — ^A contraction of the blood-vessels (arteries, capil- 

 laries, veins) can be produced by influences acting either upon the 

 nerves, the musculature of the vessels, or the blood. The various 

 organs concerned are the vasomotor centre in the medulla oblon- 

 gata, similar centres in the spinal cord, and the peripheral vaso- 

 constrictor nerves; all of which can be stimulated directly and 

 reflexly. Contraction of the blood-vessels causes a decrease in the 

 amount of blood in the tissues they supply and an increase in the 

 blood-pressure. Other vasoconstrictor drugs act by coagulating 

 the blood or by withdrawing fluid. Vasomotor constrictors are 

 divided into two groups : external and internal. The most impor- 

 tant external vasoconstrictors are silver nitrate, lead acetate, 

 copper sulphate, zinc sulphate, zinc chloride, bichloride of mercury, 

 iron sulphate, alum, tannic acid, adrenalin (suprarenin), chalk 

 and also mild cutaneous irritants. The most important internal 

 vasoconstrictors are ergot, hydrastis, digitalis, caffeine strophan- 

 thus [atropine, strychnine and cocaine]. 



Uses. — The vasomotor stimulants are used to arrest hemor- 

 rhage (see previous chapter); to overcome hypersemia, stasis and 



