Prince Harry fell ill during his South Pole trek, after he was left weakened, dehydrated and in pain by altitude sickness and exhaustion.
The dramatic scenes will be screened on Sunday in ITV's second episode of his documentary about the challenge, Harry's South Pole Heroes.
The Prince can be heard groaning loudly as he is being checked by a medic.
Watch Prince Harry talk about his health scare in the South Pole:
The prince was forced to rest for 36 hours while journeying across the Antarctic plateau on foot during the December challenge.
"Antarctica jumped up and bit me on the ass," he admits.
He said he was "frustrated and disappointed" in himself.
"It proves how mentally and physically tough these guys are," he said of his fellow trekkers, some of whom had lost limbs during service in Afghanistan.
– Prince Harry, speaking in Harry's South Pole Heroes, Episode 2
Being tent-bound really sucks. I don't really enjoy sitting around and doing nothing, especially when I know they're walking 17km.
The scenes involving his health scare will be screened on Sunday in the second part of ITV's documentary about the polar adventure.
Harry undertook the journey dragging his sledge of supplies more than 124 miles (200km) over the snow and ice, alongside 12 servicemen and women from the UK as well as teams from other nations in the Walking With The Wounded expedition.
During the eighth day, after a nagging headache, he tells a medic: "It feels as though it's expanding. It's getting worse and worse."
He is seen being tested to check he still has feeling in his limbs and asked about whether he has vomited as a result of his condition.
Harry explains later: "If you show a weakness to Antarctica, I think it exploits it. And I think it will slowly grind you down until you have the utmost respect for it, which I now have.
"I thought I could come out here and just crack on and see it through without any issues, make sure I'm here for the guys when they need me.
Harry's South Pole Heroes Episode 2 will screened at 8pm on Sunday on ITV.