OEGANIC POISONS AND DEUGS 125 



It is eliminated rapidly, and unaltered in the urine, by 

 whatever channel it is given. 



Artificial respiration is successful in combating curare 

 poisoning mainly by reason of the rapid elimination of the 

 alkaloid. 



As with the other medicinal alkaloids, there is little like- 

 lihood of curare poisoning occurring outside of possible 

 overdosage. 



YOHIMBINE. 



Occuprence. — Yohimbine is an alkaloid derived from the 

 bark of the Coryanthe yohimbi (Schumann), found in the 

 Cameroons. 



It is given in the form of the chloride in doses of grains 

 I for the stallion, IJ for the bull, IJ for the cow, ^ for the 

 sheep, -^jj to -^^ for small dogs, /^ for dogs from 20 to 50 

 pounds, and J for dogs over 50 pounds. These doses may 

 be repeated three times a day (Finlay Dun) . 



Effects. — Yohimbine has recently assumed importance as 

 a powerful non-irritant aphrodisiac drug, which excites the 

 spinal erection centre and congests the genital organs. 



Poisoning has not often been observed, but Finlay Dun* 

 states that dogs have been killed by ^ grain, displaying 

 dyspnoea, depression of the heart, salivation, diarrhoea, a 

 low temperature, partial paralysis, and convulsions. 



Although poisoning could not occur save as the result of 

 careless dosage, it is well to point out its possibility, espe- 

 cially in view of the rather wide use of the drug, and the 

 likelihood of inexpert employment. 



Chemical Diag'nosis. — Yohimbine gives with strong sul- 

 phuric acid and potassium bichromate a dirty greenish-blue 

 colour, rapidly passing to dirty green (not characteristic). 

 When yohimbine is mixed with a drop of a solution of 

 benzaldehyde in alcohol (1 to 4), and a drop or two of 

 sulphuric acid is added, the mixture is at first dark brown, 

 then gradually (first at the edges) becomes cherry-red, and 

 finally violet. 



* ' Veterinary Medicines,' 1910, p. 618. 



