The brown tree snake, Boiga irregularis, is abundant on Guam and commonly invades human habitations. Data on emergency room visits on Guam document a high frequency of snakebites on Guam. Over 50% of the emergency room visits for snakebite involved children less than 4 years old. Records exist of 4 infants, 1, 2, 5, and 10 months old, who displayed significant symptoms after being bitten, while sleeping, by snakes. Two infants developed respiratory problems within a few hours and required medical treatment for asphyxiation. Lethargy, diminished sensory perceptions, drooping eyelids, swelling, discoloration, and bleb formation were variable in occurrence in the patients.