300 VEGETABLE DRUGS 



dogs in pills or tablets, and to horses in solution dropped on the tongue. 

 Nux vomica is given to horses upon the food in the form of powder, or 

 in fluidextract upon the tongue ; while the tincture is more appropriate for 

 dogs. When large doses of strychnine are used, or an immediate action 

 is desired in acute diseases and emergencies, the alkaloid should be given 

 hypodermically. 



Toxicology. — One-twentieth of a grain of strychnine nitrate, in- 

 jected subcutaneously by the writer into a dog weighing 25 lbs., caused 

 uneasiness and excitement, with protrusion of the ej'e-balls, and in the 

 space of ten minutes, tetanic convulsions. The breathing was shallow and 

 almost imperceptible, the pulse rapid and irregular, the lips were covered 

 with foam, the tail was stiff and extended, the ears laid back, and there 

 was general muscular rigidity the animal lying on his side in a state of 

 opisthotonos. This condition lasted about three minutes, and was fol- 

 lowed by a period of relaxation. But the slightest noise or irritation of 

 the skin brought on convulsions. The convulsions became less frequent 

 and violent, and ceased altogether within half an hour. The same animal 

 was given gr. 1/40 of the alkaloid on the following day, but without pro- 

 ducing any appreciable result. One-tenth of a grain, given on another 

 day and in the same manner, caused immediate uneasiness and restless- 

 ness, and in ten minutes induced a severe convulsion, lasting for three 

 minutes, in which the animal was so rigid that he could be lifted bodily 

 without bending. > The ears were drawn back, the limbs were extended 

 and stiff, the tail was straight and rigid, and there was twitching of the 

 muscles of the jaw and limbs. The corners of the mouth were drawn 

 back (risus sardonicus), the mouth was covered with foam, and there 

 was some trismus. The breathing was nearly suppressed, owing to tetanic 

 spasm of the respiratory muscles. Following this convulsion, the jaw 

 dropped, the muscles relaxed and another attack could not be produced 

 by noises or external irritation. Some twitching of the temporal muscles 

 persisted. Evidently the second stage of poisoning had ensued, and the 

 motor nerves and cells of the inferior eornua had become paralyzed. 

 Death occurred in general paralysis within half an hour, and without any 

 recurrence of convulsions or tetanic condition. Death takes place more 

 commonly in strychnine poisoning from asphyxia, during a convulsion, 

 and is caused by spasm of the respiratory muscles, or, more rarely, by 

 spasm of the glottis. Sometimes death ensues, after enormous doses, in 

 general paralysis from depression of the respiratory centre — without the 

 occurrence of convulsions. Rarely death occurs from exhaustion between 

 the paroxysms. When strychnine is given medicinally in large doses the 

 appearance of restlessness, excitement, and muscular twitchings, should 

 warn one of the danger of approaching poisoning. 



The lethal dose for dogs has been set at gr. l/6-gr. 1/3. This is 

 much too large, as evidenced by the experiment mentioned above. The 

 fatal amount varies greatly in accordance with the weight of an animal; 

 probably less than gr. 1/20 by the mouth would kill toy terriers, and 

 cases are reported where they have been destroyed by gr. 1/60 of the 

 alkaloid. The therapeutic dose should therefore be proportioned as 



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