Fiona says hers was from the heater at her house, and that her "demons" - such as her alcohol addiction - stopped her from noticing the signs.
“It went over the course of a month. I forgot things, I thought I was getting early Alzheimer’s," she said on Gold104.3’s Jo & Lehmo show. I was forgetting things, forgetting my kids’ names."
"I was forgetting things, forgetting my kids’ names. But then I did forget I was an alcoholic.”
She says that, eventually, the carbon monoxide poisoning almost killed her, leaving her in a coma for over a month: I was “very, very unwell.”
“I was given a 7 per cent chance of life. Guess what? I didn’t die,” Fiona said.
The comedian also revealed that upon waking up from her coma, her sisters played a pretty hilarious joke on her.
“Emily and Kate, my two sisters, played the worst joke on me. I’m three days out of a coma. They were talking into their wrists, and Emily said ‘They’re microchips in our wrists. We’ve all got them.’ Kate said, ‘You know you’ve been in a coma for seven years?’ I lost my mind."
This article originally appeared on Marie Claire