Prime Minister John Key has described fainting in a Christchurch restaurant as an "out-of-body experience" where he could hear voices but was unable to respond.
Key collapsed in a packed Italian restaurant in Merivale about 9.15pm on Thursday.
Witnesses said he looked pale and sweaty before fainting.
Key stood up to leave the restaurant, but his legs buckled and he fell against another diner's chair.
He was rushed to Christchurch Hospital, where he was given an ECG and had blood tests during a two-hour stay in the emergency department.
Seen by specialists, one of whom was an expert in people fainting, he was cleared to travel to Antarctica yesterday morning.
On the flight down to the icy continent, he revealed it was his wife, Bronagh, who caught him as he fell.
"She was my lady-in-waiting," he said.
As they prepared to leave the restaurant, his wife had asked him if he was OK, but he did not answer her.
Key was confident he had recovered from whatever caused him to collapse. "I feel totally fine."
Antarctica New Zealand officials he was dining with suggested he was suffering from jet lag after flying back from Hawaii on Thursday morning.
However, former Prime Minister Sir Geoffrey Palmer suggested Key's collapse was linked to his demanding workload, and he recalled suffering a similar misadventure while deputy prime minister.
"I had been working from 7am and I hadn't had much to eat and I went to Government House for the evening and I fainted," he said. "I just remember coming to, and the governor-general looking after me."
Palmer had been working about 17 hours a day at the time and believed he fainted from exhaustion.
"That's the sort of thing that happens in this job because the hours are horrendous, there's a lot of travel and the result of it is you get exhausted. I think exhaustion is one of the biggest factors in politics," he said.
A "standard" day's work usually ran from 7am to midnight, and Palmer thought the pressure of the job would have been a "big factor" in Key's collapse.
"My sympathy goes out to Key because it is a very difficult job."
Felicity Plummer, the manager of Tutto Benne, where Key was dining, said he and his entourage of 10 arrived about 7.30pm.
She thought Key looked unwell during the night and commented to a colleague that she doubted he would make it through dinner.
"He looked extremely tired and he was perspiring," she said.
After he finished his meal she saw him get up from his seat and his legs buckle.
He was heading towards the floor when someone next to him grabbed him under his armpits and tried to hold him up.
Key appeared to lose consciousness for a few seconds and was dazed when he came to.
Other diners gasped in shock as Key collapsed, but gave his protection officers room to take care of him, she said.
A man dining at the next table said Key hit the back of his chair as he collapsed. "He looked really pale and really sick. He just sat there and face-palmed for about 10 minutes, and then he got up and people helped him out."
The diner said it was not overly hot and stuffy in the restaurant, and Key had been relaxed and "animated" before collapsing.
Plummer said she gave Key water while another staff member fanned him with a menu.
He was "gracious" and smiled throughout, she said.
"I felt sorry for him. He just looked absolutely exhausted," Plummer said. "Poor man, I would think he would need to take a bit of a rest now."
A spokeswoman for Key said he had been seen by three specialists at the hospital but they had not given a reason for the fainting. "They said these things happen sometimes. He was given a clean bill of health."
Wednesday: 6am: Arrives back in New Zealand from holiday in Hawaii. 10am: Flies to Hawke's Bay for Sir Paul Holmes' investiture before returning to Auckland to spend the night at home.
Thursday: 7.30am: Flies to Wellington. 2.30pm: Flies to Christchurch to join late afternoon flight to Antarctica. Flight to the Ice is postponed until yesterday. His party go out for dinner at Italian restaurant Tutto Bene (translation: "OK") where he faints and is taken to hospital for medical checks.
- © Fairfax NZ News
A "fat tax" on sugary drinks is:Related story: PM rejects 'fat tax'