CHAPTER X. 



SYMPTOMS OF VENOM POISONING IN MAN. 



The symptoms produced by the bites of venomous snakes vary according 

 to the families to which they belong. Thus, the symptoms of cobra poison- 

 ing differ from those of crotaHne or viperine poisonings. Speaking in general, 

 the local manifestation of poisoning is much more pronounced in the latter 

 than in the former cases. This rule is, however, not general, as some mem- 

 bers of the colubrine snakes, for example the Australian genera, seem to 

 stand nearer to the Crotalinai or Viperinae in their energetic attack on the local 

 tissues. I do not intend here to discuss these differences and their causes, 

 but will simply describe the symptoms observed by various authors in human 

 cases bitten by various groups of venomous serpents, 



THE VIPERID^. 



CROTALUS POISONING IN MAN.* 



Men are more frequently bitten than women. The situation of the wound 

 is usually upon an extremity. The earhest symptom of the snake bite is 

 the pain of the wound, although this is not reported in some cases. Haem- 

 orrhage from the wound is very common, but may depend upon the size of 

 the external opening of the wound inflicted by the fang, or perhaps, also, 

 upon the character of the vessels accidentally penetrated by the fang. The 

 primary local symptoms thus described increase progressively, so that within 

 a period which varies extremely, the swelling and discoloration extend up 

 the bitten hmb, accompanied by pain of the most excruciating character. 

 At this time, or after the first few minutes, the increase in the local symptom 

 is probably due to the influence of the destructive action upon the tissue near 

 the wound, to the irritation thus resulting, and to the indirect effect of venom 

 upon local circulation. Thus the extremity becomes larger and more and 

 more discolored until the skin shows every tint of an old bruise. Vesica- 

 tions may appear on the surface, the pain lessens, the local temperature, early 

 diminished, falls still lower, and unless the poison has ceased to act, gangrene 

 ensues, and the tissue becomes necrotic. If, on the other hand, the poison is 

 not present in a dose large enough to insure these effects, the swelling declines 

 and the pain disappears with a celerity which the practitioner or reporter 

 has assumed to be evidence of his own skiU or of the utihty of his therapeutic 

 means, but which is an essential and most striking feature of crotalus poison- 

 ing. The extent of damage brought about by the crotalus bite upon the local 



' This account is derived from the work of Weir Mitchell. 



106 



