Adam Young and Brendan Dawson, both from St. John's, were flying from Bogotá, Colombia, to Mexico City when they decided to take a nap.
"We had a full row of chairs each, perfect for napping," Young said in a Facebook post on Saturday.
"I was just about asleep when I felt an insect crawl in under my shirt," wrote Young, who is currently inaccessible by telephone.
Young said he tried tried to swipe it off — but it was too late.
"The scorpion had already done it's work on me and stung me three times," he said.
"I jumped up out of my chair in a huge commotion and it fell out of my shirt on to the chair."
He said at first Dawson thought he was joking around, until he saw the critter move across the floor and under a chair.
They immediately notified the flight attendants, and then found and killed the scorpion.
"At this point, the venom was setting into my veins and the pain excruciating," he said in the post.
"This burning sensation was coming over me, and even though I remained calm on the outside I was dying on the inside."
Race against the clock
The plane they were travelling on instantly turned back towards Bogotá.
"The flight back was the longest 20 minutes of my life," wrote Young.
"Pain, nausea, chest pains, hallucinating and thinking that I was gonna die made it hell."
Young said there was an ambulance waiting for him on the tarmac when the plane landed. Once he got off the plane, he was taken to a medical examination room where they injected him in the buttocks with some anti-venom.
He said the cabin crew did a thorough search on the plane for other scorpions, finally clearing the aircraft two hours later.
"At this point the pain had subsided slightly and I wasn't letting that stop me from making it to Mexico," said Young.
Highly poisonous insect
Young said there was a man on the plane who was familiar with scorpions, and told him that he was stung by a highly venomous species.
"[It] could potentially kill a human," he wrote.
"I am still feeling the affects of this, but I am alive … lucky to be alive actually."
"It's crazy [be]cause I spent 3 days in the amazon jungle with nothing more than a few mosquito bites, then jump on a plane and get attacked by a friggin' scorpion."
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