A black Labrador has been rescued from the UK’s highest peak after falling seriously ill from apparently eating discarded cannabis on the climb with her owner.

Dog trainer Christina Bluhme was halfway up the 1345-metre Ben Nevis earlier in July when her Labrador, Tokyo, lost the use of her legs and began drifting in and out of consciousness.

“This weekend’s trip to Scotland turned into something I could never have imagined,” Bluhme said.

“While hiking, Tokyo suddenly became critically ill after ingesting what the vets believe was cannabis left on the trail.

“She quickly lost the use of her legs, drifted in and out of consciousness, and I genuinely thought I was going to lose her.”

Fortunately for Bluhme and Tokyo, the Lochaber Mountain Rescue Team rushed to their aid. They stretchered an unconscious Tokyo down from peak to a local vet.

“Without the incredible Lochaber Mountain Rescue Team, there is simply no way I could have got her safely off the mountain,” Bluhme said.

“Carrying a 25-kilogram Labrador down Ben Nevis was impossible on my own.

“Their kindness, professionalism and calm support meant everything during one of the most frightening days I’ve ever experienced.”

She said Tokyo remained unconscious for most of her journey down the mountain and to vets in Fort William.

Bluhme said she felt “incredibly lucky” that Tokyo had survived and thanked rescuers and the vets for their “compassion and dedication”.

“You were there when we needed you most,” she said.

“A little reminder to fellow dog owners – please be aware that discarded drugs and other toxic substances can sometimes be found even in the most beautiful outdoor places.

“It was something I never imagined we would encounter.”

Lochaber Mountain Rescue Team said it was pleased Tokyo had fully recovered.

“It’s now suspected that Tokyo, a usually very fit and active working dog, had ingested something that made her critically unwell,” they said.

They also thanked the local vets, and Bluhme for sharing her update.

Australia’s Animal Poisons Hotline warns that dogs are much more sensitive to the effects of marijuana than people. They metabolise the psychoactive constituent, D9-tetrahydrocannabinol (THC), much more slowly and also have a higher number of cannabinoid receptors in their brains.

It says poisoning can occur through eating the plant (including via joints), foods made with marijuana as an ingredient or by inhaling the smoke.

Common signs of marijuana poisoning include wobbliness (ataxia), dilated pupils, sensitivity to sound/light/touch, disorientation, urinary incontinence and reduced alertness.

“Sadly, many pets have died from the severity of the poisoning,” the hotline says.

“Fortunately, with early intervention, most animals can be treated successfully and the prognosis for full recovery is excellent.”