300 The Pharmacological Action of South African Boxwood. 
man. It follows then that if it can be clearly shown clinically that poisoning 
definitely follows the use of boxwood in the case of certain men, and from 
Dr. Hay’s* report this cannot be doubted, then these must possess a very 
extraordinary and marked idiosyncracy. 
It is well known that some neurotic people, and by these I mean a class 
in whom a certain type of afferent stimulation produces an excessive efferent 
effect, are peculiarly susceptible to nerve poisons and to certain stimuli; 
as an illustration it is only necessary to refer to spasmodic contraction of 
the bronchicles from nasal irritation and to hay fever from pollen. Boxwood 
may claim its victims in the same way; it may be absorbed from the nasal 
mucous membrane and produce exaggerated local effects, increasing nasal 
reflexes, causing asthmatic conditions and catarrh, and the other symptoms 
noted. That it is possible for a drug absorbed locally to act locally we know, 
since strychnine injected into one temple of a man increases the field of 
vision on the eye of that side, and is almost without effect on the opposite 
eye. Some such explanation in many of the recorded cases of poisoning is 
the only one which I can offer as being in agreement with the facts, and 
it is supported by the records that only a small percentage of men working 
the wood have been affected, and that the commonest symptoms are those 
which most usually arise reflexly—headache, irritation of the eyes, nasal 
catarrh, and respiratory trouble, possibly asthmatic. So that although 
boxwood is a poison belonging to the curare group it is probably not to the 
general specific effects of the alkaloid after absorption that the majority of 
the recorded cases of poisoning must be credited. 
* Annual Report of the Chief Inspector of Factories for 1908, p. 266. 
