A woman in her 40s is lucky to be alive after she was potentially bitten by an eastern brown snake, before it became trapped in her shoe.

Snake catcher Cory Kerewaro said the woman had been geocaching, a treasure-hunt-style game using online GPS coordinates, in bushland in south-west Sydney on Saturday, when she felt something slither around her leg.

A snake is coming out of a shoe.

This eastern brown snake was wedged in the woman’s shoe. (Supplied: Reptile Relocation Sydney)

“She’s gone to jump out of the garden bed, gone to shake her leg off thinking a big leaf had wrapped around her leg and it was actually an eastern brown snake,” Mr Kerewaro said.

Mr Kerewaro said the venom from an eastern brown snake, in some circumstances, could kill in less than 15 minutes.

“Eastern brown snakes are responsible for the most recorded deaths in Australia from snake bites; they take the top of the list.”

He praised the woman’s willpower to stay calm, as the agitated snake then became trapped in the heel loop of her sneaker.

“When she noticed it was a snake, she stayed absolutely still, and that’s when it went through the loop and got itself caught,” Mr Kerewaro said.

“It’s nearly unbelievable; something like this tops anything I’ve done.”A snake beside a woman's shoe.

The snake had to be removed after it got stuck in the woman’s shoe. (Supplied: Reptile Relocation Sydney)

Paramedics and Mr Kerewaro were called to the Narellan scene around 3:30pm on Saturday.

“They couldn’t access the patient until they weren’t at risk either, so it was quite bizarre,” Mr Kerewaro said. 

“We quickly pinned the snake, undid the lady’s shoe and got her out of danger’s way …The paramedics absolutely saved her life.”Snake bite app

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NSW Ambulance acting duty operations manager Linda Evans said once freed from the snake, they were able to treat the woman for possible bites.

“There were some marks on her legs, which they weren’t sure whether they were bite marks or just scratches from the bushland,” she said. 

“As a precaution, we treated it as snake bite … we applied a bandage to the area, a box splint for limb immobilisation.

A snake stuck in the loop on the back of a shoe.

The snake got stuck in the loop on the back of the shoe. (Supplied: Reptile Relocation Sydney)

“Our intensive care paramedics carry certain medications that can assist in slowing down the onset of those symptoms … we make sure the patient is stable and get them as quickly as possible to a hospital that carries an antivenene.”

Mr Kerewaro said he had spoken to the woman, who was recovering from the incident. 

“She’s just going to take a couple of days’ rest and process it all, but she’ll be OK,” he said.

“If you do see a snake, the best thing you can do, like that lady, is to stay still.

“[Snakes] react to movement, so the more you stay still, it’s the best thing for you. If it’s a safe distance, back away slowly.”