Updated

Scorpions are alternately cherished and feared in parts of northern Mexico, where stings are common and the dead critters adorn key-chains and ornamental ashtrays.

Now Mexican scientists are bringing to the United States the result of years of experience battling the sometimes-deadly effects of their stings with a newly approved anti-venom.

The product, sold in the United States under the name Anascorp, was developed by scientists at Mexico's National Autonomous University and the private Instituto Bioclon.

It was tested at U.S. emergency rooms on more than 500 victims of painful scorpion stings before gaining U.S. Food and Drug Administration approval on Wednesday.

The FDA said Anascorp is made from the plasma of horses immunized with scorpion venom and its developers say the antidote is the first Mexican drug to win approval from U.S. health authorities. Researchers have high hopes that it can save lives in southwestern U.S. states where stings are common.

Scorpions prick an estimated 10,000 Americans each year, mostly in Arizona, and more than 250,000 Mexicans, the serum's developers said. Injections of Anascorp counteract the stings within two hours by neutralizing the scorpion's poison.

"This is extremely important in the United States and particularly in Arizona where we have the most bites," said scientist Jose Lever, who oversaw clinical trials for the drug in the United States. "Before this there was no anti-venom and patients had to undergo intensive treatments."

There are more than 1,000 species of scorpion — about 50 of which are dangerous to humans.
Victims with severe reactions can go into convulsions and choke on their own saliva, according to experts at the University of Arizona. Intensive-care doctors often have to heavily sedate and intubate them.