He reportedly broke down multiple times during the emotional interview as he admitted his responsibilities were taking a personal toll.
“This past year has been the most difficult and painful year of my career,” he said. “It was excruciating."
By early Friday afternoon, Tesla’s shares had fallen over 8%, wiping about $4bn off the company’s value.
Musk, whose company posted a record $709.6m net loss in the first quarter of this year while struggling to manufacture large numbers of its Model 3 mass-market electric car, said he had been working up to 120 hours a week and his health had been “not great”. He said his friends had been worried about him.
Musk said there were times he didn’t leave the factory for three or four days at a time and days when he didn’t go outside.
He said he spent the entire 24 hours of his 47th birthday in June at work and flew directly to his brother’s wedding, where he was due to be best man, from work, arriving two hours before the ceremony and leaving immediately afterwards.
It has also been reported that Tesla executives are increasingly worried about Musk's reliance on Ambien to help him sleep and its possible effects on late-night Twitter sessions.
Various episodes of bizarre behaviour have provoked a string of headlines and led to growing concerns about the billionaire's stability and the turmoil in Tesla’s share price as markets responded to his outbursts.
He recently berated analysts for asking boring questions during an earnings conference call, accused a British diver who helped rescue a Thai football team trapped underground of being a paedophile, and last week published a tweet claiming he had secured funding to take Tesla private, sparking a rollercoaster ride for shareholders that is now under investigation by the Securities and Exchange Commission.
Mr Musk has long delighted in his reputation as one of Silicon Valley’s brashest entrepreneurs but admitted exhaustion was taking its toll.
“It’s not been great, actually,” he said. “I’ve had friends come by who are really concerned.”
Tesla is also being sued by several investors after Musk' surprise (and completely fantastic as it turns out,)announcement that he planned to take the company private, following his failure to progess from a niche business making overpriced, pimped up mobility scooters for Hollywood liberals with more money than sense into a major car maker competing with Mercedes, BMW, VW Audi, Land Rover Jaguar and Lexus