From the Arizona Daily Star:

_The victim experiences extreme pain at the location of the bite, nausea, sometimes diarrhea. Then the mouth and throat swell, making it difficult to breathe. The victim gets lightheaded, collapses and goes into shock — all within minutes of the strike.

The potentially deadly symptoms used to be fairly rare, but toxicologists in Arizona, Colorado and California say they’re seeing some or all of them more than ever, and they could be contributing to an increase in fatal rattlesnake bites in Arizona._