OPIUM AND MORPHINE 341 



Pigeons cannot be given enough opium l»y the mouth to 

 cause death, but 8 to 10 grs. of morphine per orem, or 2 or 

 3 grs. hypodermatically, will prove fatal. The toxic symp- 

 toms in birds are exhibited by unsteadiness, difficult 

 breathing and failure of respiration, convulsions and death. 

 The pupils are unaffected, and sleep does not ensue. 



Action Upon Dogs. — When 8 or 10 grains of morphine 

 are given to a moderate sized dog, coma comes on, from 

 which the animal may recover. One half a grain injected 

 under the skin of a dog weighing 25 lbs., causes nausea, 

 vomiting and perhaps purging, sleep deepening into coma, 

 contracted pupils, and shallow breathing ; the condition 

 lasting for several hours and followed by recovery. Opium 

 rarely exerts an hypnotic action upon cats, but rather motor 

 excitement. Lethal doses (average, 4 grains of morphine 

 sulphate subcutaneously to the pound, live weight, for dogs; 

 2 to 3 grains sometimes kill small dogs), increase the 

 frequency of the pulse, cause vomiting, unsteadiness, con- 

 tracted pupils, motor excitement, as twitching of the limbs 

 and convulsions, followed by coma, respiratory failure and 

 death. Recovery from full doses of opium is accompanied 

 in dogs by general physical and mental depression and 

 lassitude, as in man. There are muscular weakness, loss of 

 natural spirit, timidity, and nausea, lasting for several hours. 

 The action of opium upon dogs differs from that upon man 

 only in degree. The dose required is proportionately larger. 

 There is often more preliminary excitement and symptoms 

 of reflex irritation, as muscular twitching. These animals 

 do not sweat, and the pupils are not so continuously con- 

 tracted in poisoning. Failure of the drug to produce sleep, 

 . nd the presence of nausea, retching, dreams, delirium, 

 hallucinations, occasionally observed in dogs, are common 

 to man. Convulsions rarely occur in either men or dogs. 



Action Upon 3Ian. — In man, a small dose of morphine 

 (i 8^') causes usually a sense of well-being, together with 

 itching of the nose, and later, of the skin generally, dryness 

 of the mouth (occasionally there may be nausea, vomiting 



