A British teenager has told rescuers he survived three days lost in outback central Queensland by drinking his urine.

Samuel Woodhead, 18, got lost in bushland while jogging on a remote property south-west of Longreach on Tuesday.

He was found by searchers in a helicopter yesterday, about 5.5 kilometres from the property he was working on.

Temperatures reached 40 degrees in the area.

Mr Woodhead's mother Claire Derry, who has visited him at the Longreach hospital, says he also drank contact lens fluid to survive.

"His father had packed boxes of contact lenses in his rucksack in an outside pocket and he'd forgotten to take them out," she told This Morning.

Found: British backpacker Sam Woodhead ( Facebook )

"He's literally lived on those packs of contact lenses for three nights."

Ms Derry says her son has lost about 15 kilograms and is still very weak, but looks well.

"He must have the constitution of an ox," she said.

"He looks fantastic, his mouth isn't blistered, he's questionably a lot thinner than when I saw him.

"The only concern is that his kidneys are not quite functioning normally and his blood's not normal, but the doctors say that's completely typical of someone who's been completely dehydrated.

"He is an incredibly lucky young man and we're incredibly lucky that the people kept on looking for as long as they did."

Inspector Mike Curtain says Mr Woodhead is a very lucky man.

Mr Woodhead is expected to be released from hospital tomorrow.

Several helicopters, aircraft from neighbouring properties, SES and police had been called in to search for him.

A number of SES volunteers were treated for heatstroke during the rescue operation, with two taken to hospital.