128 VETEKINAEY TOXICOLOGY 



sitae, both grow in Great Britain, but are not likely to be 

 eaten by small animals. The effects of the active principles 

 on larger animals are not serious. Wormwood yields oil of 

 absinthe, a narcotic poison causing trembling, stupor, and 

 convulsions in dogs. It is used as a remedy for worms. 

 Its consumption in the form of absinthe gives rise to the 

 very grave chronic absinthism in man. 



Santonin, derived from the flower heads of A. maritima, is 

 very commonly used as a vermicide for round and thread 

 worms, the doses for dogs being from f to 3 grains, and for 

 cats and small dogs from |^ to |- grains. 



Symptoms and Treatment.— Overdoses are dangerous, 

 and sometimes fatal. They cause in dogs twitching of the 

 head muscles, rolling of the eyes, grinding of the teeth, 

 rotation of the head, and epileptiform convulsions, followed 

 by clonic spasms. During the spasms the respiration is 

 disturbed, and asphyxia may occur (Cushny). Santonin 

 imparts a blood-red colour to the urine. It has been 

 known to cause temporary blindness in the dog. 



Poisoning is to be treated by emetics and purgatives. 

 The convulsions are prevented by chloroform, chloral, or 

 bromides, and artificial respiration is used if necessary. 



Chemical Diagnosis. — (1) Santonin in solution in a 

 little alcohol is heated in a dish at 100° C. with 1 or 2 

 drops of 2 per cent, alcoholic furfural solution, and 2 to 

 3 e.c. of strong sulphuric acid. The liquid becomes purple- 

 red, blue-violet, dark blue, and after several hours deposits 

 a black precipitate (delicacy ^^ grain, Thseter). (2) San- 

 tonin is heated with a mixture of 2 of strong sulphuric 

 acid to 1 of water until the liquid is yellow, and after 

 cooling a trace of ferric chloride is added. This gives, as a 

 rule, a turbidity, whilst on again heating there is a violet 

 coloration (delicacy ^^, Lindo). 



When a suspicion arises that harm has been caused by 

 overdosage of santonin tablets, the recognition, and, if pos- 

 sible, weighing of santonin, removed from organs, becomes 

 a very important matter from the medico-legal point of 

 view. 



