MODE OF ADMINISTRATION 7 



for soluble, non-irritating drugs of small bulk, when a sure 

 and rapid action is desired. The medicinal solution should 

 be free from solid particles and microorganisms. If the 

 solution is not clean, or is irritating, abscess may occur. 

 The syringe and needle must also be absolutely clean. 

 Solutions made by dropping tablets in pure drinking water 

 will rarely cause abscess, and the syringe may be made 

 aseptic by filling it with alcohol, and wiping the needle with 

 the same, previous to their employment. Solutions may be 

 preserved for hypodermatic use with boric acid (1 per cent.), 

 but soluble tablets are more convenient. 



In practising this method the hair should be removed 

 from the seat of injection — preferably the thin skin under- 

 laid by connective tissue behind the elbow or on the abdo- 

 men — and the part washed; then a loose fold of skin is 

 picked up and held firmly between the thumb and forefinger 

 of the left hand, while the needle is thrust under the skin, 

 but not into a vein or muscle. The syringe is slowly emptied 

 and the needle withdrawn, keeping slight pressure over the 

 point of injection with the thumb for a few seconds. The 

 use of irritating drugs — permissible in emergencies — as 

 Fluid Extract of Ergot, Tincture of Digitalis, Ether and 

 Ammonia, is less apt to be followed by abscess if injected 

 deeply into the muscular substance, but this method causes 

 more pain with ordinary injections. To avoid getting air 

 in the veins, all the air is removed from the syringe before 

 using, by holding it, needle upwards, and pushing in the 

 plunger till a few drops of the solution are forced out of the 

 needle. The danger of introducing air into the blood stream 

 is greatly exaggerated, however, as the writer has proved by 

 forcing vast quantities of air into the jugular vein of a horse 

 without producing any untoward symptoms. The proper 

 quantity of a solution for subcutaneous use is 5-30 minims 

 for dogs ; 1-2 drachms for horses, although large amounts 

 of salt solution may be injected into the subcutaneous tissue 

 or muscles (hypodermoclysis) with great benefit in haemor- 

 rhage, etc. (See p. 



