There's a saying among snake enthusiasts: Red-on-yellow, kill a fellow; red-on-black, friend of Jack. The phrase refers to the color configurations between the coral snake and the Kingsnake, both of which have coats of red, yellow and black but in different orders. The importance of those configurations lies in the difference between the snakes: King snakes are largely harmless and eat other snakes, while coral snakes are among the worlds' deadliest.
Should you find yourself unlucky enough to be the recipient of a coral snake bite, you're in luck, because antivenin to alleviate the effects of the venom exists-but maybe not for much longer.
As FDA explains on its website, the antivenin, known as Antivenin Micrurus fulvius (equine origin), was manufactured by Wyeth Pharmaceuticals, which is now owned by Pfizer. The key word there is was, as neither Wyeth nor Pfizer still manufacture the product.
"There is no alternative product licensed in the US for coral snake envenomation," FDA's notice observes.
So with a shortage of existing supplies in effect, FDA has turned to a tactic it already uses to keep supplies current in the US Strategic National Stockpile (SNS): Expiration date extensions.
While nearly all healthcare products are marked with expiration dates, those are sometimes reflective of conservative estimates not necessarily reflective of the product's true date of expiration. For anyone bitten by a coral snake, that's good news, as FDA has announced that any of the remaining supply from Lot 4030026 can be used safely through 31 October 2014.
At present, there are just two lots of the antivenin left. The other has an expiration date of April 2014 (#4030024). Both have now been extended far beyond their original use-by date of October and April 2008.
There is currently no alternative FDA-approved supplier of the antivenin, and Wyeth wrote in a letter to healthcare providers that it was "imperative that you do not discard any product you have in your inventory of Lot #4030026."
"Extension of the expiry date for lot 4030026 will enhance supply continuity," FDA added. And with no plans to re-start production, people who encounter the snakes should hope that "continuity" lasts for as long as it can.
Wyeth 'Dear Healthcare Provider' Letter