An Aussie surfer has been rushed to hospital after a run-in with a box jellyfish on a world-famous reef break in Fiji.

Guy Rowles was surfing Cloudbreak with his dad last week when he was stung by an Irukandji jellyfish — the world’s most venomous sea creature.

The small but deadly jellies are common in tropical waters, and their tentacles contain millions of microscopic stingers which emerge upon contact, and inject a venom potent enough to cause heart failure and swelling of the brain.

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Days before Rowles’ life-threatening sting, the Fijian Ministry of Health and Medical Services put out a warning “urging Fijians to take precautionary measures when out at sea with the presence of box jellyfish.”

“A number of patients have been presented to the Ministry’s Hyperbaric Unit with breathing problems.”

Rowles was roughly 4km off the coast of Namotu Island when he was stung.

He described the incident on his Instagram as a “pretty wild experience”.

“Definitely puts things in perspective,” he said.

Guy Rowles was rushed to hospital after he was stung by a box jellyfish while surfing Cloudbreak in Fiji. Credit: Instagram

He told surf magazine Stab about the terrifying moment he lay convulsing in the boat, asking his dad “am I going to die?’”.

Rowles was rushed to the mainland, and later thanked the team at Sujees Surf Stay for getting him to the hospital so quickly.

But hospital staff reportedly told the surfer upon arrival they could not give him anti-venom as too much time had passed between Rowles being stung and his admission to the hospital.

He was doused in vinegar, dosed up on morphine, and told he had to “ride it out”, according to Stab .

“Grateful for everyone who helped me today,” Rowles said in an Instagram post.

Rowles was back on his board within days, and said he was “grateful to be back in the water doing what I love”.

Despite the dangers in the water, Rowles said the Fiji surf break was “still paradise”.

Guy Rowles thanked the Sujees Surf Stay team for saving his life after he was stung by a box jellyfish. Credit: Instagram