🚀 go-pugleaf

Monahan's report of being bitten by lots of Garters with no problems and
then suddenly having a reaction, on occasion, to bites of some species is
not unusual.  Colubrids that are highly agitated and  biting for 
defensive  purposes are less likely to produce significant toxins 
because (the fight/flight) the adrenalin they produce  is a constictor
of Duvernoy gland ducts.  On the other hand it has been noted that 
snakes biting human hands during the act of feeding are more likely
to cause problems since the Duvernoy glands are are more apt to be
flowing.  There are also differences among species and individuals of 
the same species.  I would be interested in knowing whether the problems
encountered with colubrid bites were associated with defensive bites or
bites associated with feeding stimuli.  

Also  Duvernoy gland secretions flow best when the bite is a strong one -- as 
the snake needs to get a firm grip on the surface and bear down, producing 
the pressure needed to squeeze the glands.  Unlike more advanced "venomous"
snakes, Duvernoy-gland colubrids dont have the musculature needed to 
empty these glands independently.  So the quality of the bite also counts.
There is  less  chance  to have any problem with colubrid bites that are 
merely defensive swipes or quick nips.