The Kidulthood star – who was diagnosed with bipolar disorder five years ago – said losing a friend to coronavirus triggered a mental breakdown, and apologised for his subsequent behaviour on social media.
Deacon, 37, told Sky News: “Lockdown was a difficult time; I felt like I went through every single emotion. I couldn't see anyone and at times it was very lonely...
“Then, all of a sudden, I was hit with the news that a good friend, Sean Mitchell, had died with COVID-19.”
The Bafta-winning actor said he was not allowed to attend his friend’s funeral, and that his grief, followed by the impact of the Black Lives Matter movement, pushed him over the edge and he began a series of rants on social media that led to him being banned from Instagram.
Deacon said: “This highly pressurised moment in time triggered me into a manic bipolar episode. It took over, and I began posting about my own personal conflicts.
“Before I knew it, I had gone days without any food or sleep. Looking back now, I can see my posts continued to get stranger and stranger.
“My family and friends were starting to really worry about me, but at that time I was so focused on what I was saying I couldn't understand their concern.”
He revealed: “I collapsed to the floor in a panic attack, unable to breathe. I called 999, believing in that moment that I could die.
“Within 20 minutes the police and paramedics were rushing to my door and I was taken to hospital. There I was made to wait eight hours, which was extremely distressing.”
Deacon was discharged after six days in hospital and has since been campaigning to get his Instagram account reinstated, but has not had a response from the regulators of the social media platform.
He said: “I do understand Instagram has to act if someone breaks the rules of their site, but to ban me from the platform without any discussion seems unfair and unnecessary...
“I would like to take this opportunity to apologise for my recent rants on Instagram and Twitter, and want to say thank you to everyone who has taken time to try and understand mental health issues.”
Deacon rose to fame after starring in Clarke’s films Kidulthood and Adulthood and in 2011 directed his own spoof of the movies, Anuvahood.
In 2016 he was arrested over claims he had been threatening members of the public in London armed with a knife and machete. Deacon was found not guilty of affray and possessing an offensive weapon after the jury accepted he was mentally ill and not responsible for his actions.
He previously opened up to fellow actor Stephen Fry about his bipolar diagnosis in a BBC documentary in 2016.