PHOENIX (AP) - A rattlesnake strikes.
The victim experiences extreme pain at the location of the bite, nausea, sometimes diarrhea. Then the mouth and throat swell, making it difficult to breath. 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 that they could be contributing to an increase in fatal rattlesnake bites in Arizona.
At least five people have died from rattlesnake bites in Arizona since 2002 -- three or four of them from the extreme symptoms, said Steve Curry, director of medical toxicology at the Banner Poison Control Center in Phoenix.
Curry could recall just five fatal rattlesnake bites in the two decades before 2002.
Scientists and toxicologists can take guesses at what's behind the spike in extreme symptoms, but no one yet knows what's going on. Some say it could be a change in snake venom, a change in the snakes themselves, or something altogether different.
"This is a brand new phenomenon," said Jeffrey Brent, clinical professor of medicine at the University of Colorado Health Sciences Center. "It should spur a considerable amount of research in the area."
Brent said he hadn't seen the extreme symptoms in patients until last year, when there were five. "They came pretty darn close to dying," he said. "They were extremely, extremely sick."
He said there haven't been any such bites so far this year, but that the season is just getting started.
Rattlesnake bite victims in California began showing symptoms of weakness, breathing trouble and low blood pressure this year, said Richard Clark, director of the division of medical toxicology at the University of California-San Diego.
He said about a dozen people have been affected and one patient has died since January.
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