A teenager died in 49C heat on a school trek after waiting for medical help for two hours while in the care of an inexperienced tour guide.
Samuel Boon, 17, collapsed during a trip to build a school in the High Atlas foothills in Morocco.
The inquest into Samuel's death was told that Stephen Bates, the expedition leader for the group, had only recently qualified as a tour leader and had been assessed as having difficulties communicating with young people.
Samuel, from Abbey Wood, London, had saved £1,000 for the trip. He was forced to wait for help in the heat by the roadside for two hours before a minibus, rather than an ambulance, took him to hospital.
Bromley coroner's court was told that organisers World Challenge - which offers educational expeditions in the developing world - said that emergency measures were part of the package.
William Pemberton, the school's head of sixth form, said: "They said there would be satellite phones, helicopters would be used and all the stops pulled out in an emergency."
He said no fitness regime had been suggested for the trip and that Sam was relatively fit and had a 'rugby playing' physique despite weighing more than 20 stone.
Sam's mother Karen told the court she would not have allowed him on the trip if she had known a helicopter evacuation would not be possible.
She said he had taken Desmomelt tablets, an anti bed-wetting drug which can be dangerous when taken with water. She said he suffered from bed-wetting in the past but at the time of the trip only took them on holiday for reassurance.
She said: "He was going to be sharing a hotel on one night so I packed them. There were three gone from the packet."
The inquest heard that the advice is to not drink water an hour before taking the medication and for eight hours afterwards.
Mrs Boon said she had not mentioned the medication on the application form for the trip because Sam rarely took them. She said his physical fitness was good despite him being clinically obese.
She said: "He walked to school, played golf with his father and walked the dog."
The family's GP, Dr Ananand, who prescribed the Desmomelt, said: "We had had a conversation about restricting fluid overnight but not every time (the prescription was given)."
The World Challenge trip was due to last 14 days and included a six-day trek to Amizmiz.
Samuel was one of 11 students on the trip for which they raised £12,000 through charity events.
A spokesman for World Challenge said: "Everybody at World Challenge were deeply saddened by Samuel Boon's death and we are providing all possible support to the coroner."
The inquest continues.