Sheridan Smith has revealed she suffered five seizures and was rushed to A&E after stopping her anti-anxiety medication abruptly.
In the upcoming ITV documentary, 'Sheridan Smith: Becoming Mum', the 39-year-old actress opened up about her near-fatal experience after Graham Norton made a joke about her being a drunk and halting her West End run in 'Funny Girl' due to "technical difficulties".
Speaking at the BAFTA TV Awards in 2016, where Sheridan was up for the Leading Actress accolade for 'The C Word', host Graham said: "Let's get started because, of course, the sooner we begin, the sooner we can have a couple of drinks . . . or as they say in theatrical circles, a couple of glasses of technical difficulties."
However, Sheridan was mourning from the death of her father Colin from cancer at the time and the comment pushed her over the edge.
Speaking on the doc, Sheridan recalled: "Graham Norton was hosting and made a joke, basically at my expense, about me being a drunk.
"I was so humiliated, you know, it's a room full of your peers. And people you want to work with, or have worked with.
"That night for me was like the final straw, before my brain totally went off the deep end."
The 'Cilla' star had an addiction to her tablets and decided after the BAFTAs to stop her medication, which resulted in her ending up in hospital.
Fortunately, a friend of Sheridan's came over to her hotel that night and was able to get her breathing again.
She continued: "What people didn't realise was that I'd become addicted to anti-anxiety tablets.
"That night, I took myself off to a hotel on my own.
"In my crazy mind I thought, 'I don't wanna be in rehab -- I'll do it myself' so I went there and I just stopped my tablets.
"What I didn't realise is, that if you stop the tablets abruptly, you seizure. And, to cut a long story short, I got seizures five times and got rushed into A&E.
"Weirdly, a friend of mine rang me and she came to the hotel. It's a miracle that she did. It was like someone was looking out for me.
"She's the one who got me breathing again."
It was during her stint on 'Funny Girl' that she had a meltdown.
She said: "I was going to different psychiatrists, getting different diagnoses. I then started self-medicating, drinking a lot and it was like a vicious circle. I could just see my whole life unravelling."
Elsewhere, Sheridan - who gave birth to her first child with fiance Jamie Horn, son Billy, in May - goes into depth about her pregnancy fears while taking anxiety meds.
Sheridan was "constantly worried" that her tablets would affect her baby and it caused her to have panic attacks again after stopping her medication.
She recalled: "When I got pregnant, I read online I shouldn't be taking any medication. So I stopped.
"Then I spoke to my doctor and said, 'I'm freaking out' and started having panic attacks again and not being able to get out of the house.
"And he said, 'Well, don't stop the medication. You can't just choose to stop it. You're not there yet'. I've still got the underlying issues. So I went back on the medication and that was the right thing to do.
"But I had constantly worried that it would affect the baby."
Sheridan also opened up about the death of her brother Julian, who was just 18 when he died after a battle with cancer.
She shared: "It was all perfect until my brother Julian got unwell. He was diagnosed with cancer and spent a couple of years on the couch unwell. I'd do little performances for him. He'd encourage me to sing and dance for him and I'd massage his feet.
"I have lots of lovely memories of him. I really looked up to him as he was my big, big brother.
"What I vividly remember, which is kind of annoying now, which I try to black out, was the night that he died and all the screaming."
'Sheridan Smith: Becoming Mum' airs on September 1 on ITV.