Elon Musk describes his 'excruciating' year and says he's had to take Ambien to get to sleep

Lucy Nicholson / Reuters

Tesla CEO Elon Musk.

• Tesla CEO Elon Musk says that an "excruciating" year has taken a toll on him.
• He sometimes has had to take Ambien, a prescription drug that helps induce sleep.
• Musk described an intense 120-hour work week as both chairman and chief executive of Tesla, a company that has been hit with challenging press coverage in recent weeks.
• Musk says he has not taken a break from work for more than a week since he contracted malaria in 2001.
• A person familiar with Tesla board of directors who was cited by The New York Times said some people on the board of directors suggested that Musk's Ambien use may not be effective, and instead, played a role in his social media outbursts.

Tesla CEO Elon Musk says that an "excruciating" year has taken a toll and that he sometimes has had to take Ambien, a prescription drug that assists in inducing sleep.

"It is often a choice of no sleep or Ambien," Musk said in a New York Times report published Thursday night.

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Musk described an intense 120-hour work week as both chairman and chief executive of Tesla, a company that has been hit with challenging press coverage in recent weeks. During his interview with The Times, Musk reportedly grew emotional as he described his turbulent year.

"This past year has been the most difficult and painful year of my career," Musk said. "It was excruciating."

"There were times when I didn't leave the factory for three or four days - days when I didn't go outside," Musk added. "This has really come at the expense of seeing my kids. And seeing friends."

AP Photo/Francois Mori)

In addition to his dual roles with Tesla, Elon Musk is the CEO and lead designer at SpaceX.

In June, he said he spent the entire day - his 47th birthday - at work. He flew to Catalonia for his brother's wedding two days later, flying from his factory and arriving just two hours before the ceremony, according to The Times.

Additionally, Musk says he has not taken a break from work for more than a week since he contracted malaria in 2001.

"All night - no friends, nothing," Musk said to The Times.

"It's not been great, actually," Musk said. "I've had friends come by who are really concerned."

Musk has been criticized for his occasional outbursts on social media - which include likening a British cave diver who took part in rescue efforts to a pedophile - and some of Tesla's board members have reportedly taken notice.

According to two people familiar with the board, some members were concerned about his Ambien intake, according to The Times. Some of the members also suggested that the drug may not be effective, and instead, played a part in his social media flares.

Musk later apologized for his comments and said his "words were spoken in anger" after a dispute with the cave diver.

"I thought the worst of it was over - I thought it was," Musk said. "The worst is over from a Tesla operational standpoint ... But from a personal pain standpoint, the worst is yet to come."

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