Are we there yet? ‘Cast Offs’ co-writer Jack Thorne on his new TV drama

I can accurately describe the first moment I felt like a disabled person. It was 8am on Christmas Day 2000. I'd been down for presents, but had suffered an attack and retreated to my room. Downstairs, my family were watching my VHS copy of Stand By Me. Upstairs, I was lying on top of my bed with all the windows open; I was wearing a pair of boxers and not a lot else.

The room was freezing but every time I moved my leg I was getting stabbing sensations and I was pretty sure this meant I was becoming allergic to my own body movement. Having got steadily worse over the past four months, having been tried on every type of medicine known for my condition, I'd been told by my consultant, "If this gets no better, Jack, I'm going to arrange for you to come to a conference on dermatology where a group of us can discuss your case." A few weeks earlier, I had at least been moving around a bit. Now, it seemed, I could do nothing. I was 21 years old.

I had three emotions floating in my head: self-pity, grief and self-hatred. The self-pity and grief, I think, are relatively easy to understand. I got ill having been a geek for most of my life. I'd slept with only one woman, I'd seen only three others naked. I'd always been moderately popular, but never had a best friend. I'd punched only two people, and one of them was my little sister. I'd wasted too much of my life doing VHS mix-tapes (my own invention – essentially like mixed audio tapes but videos, on a four-hour tape I'd record a film, then a bit of a TV show, then maybe a segment of a chat show... so much fun) and I wasn't even sure VHS technology would last. I'd not proved myself great yet.

I was grief-stricken for a life I now thought was beyond me. But the overwhelming emotion I was undergoing was slightly more harmful and destructive. My diaries from that period have one phrase repeated over and over again: "You are pathetic." Having talked to many "born-agains" since (not my phrase, but I love it – people not born disabled but who become so), most have had similar experiences of self-hatred.

My condition, chronic cholinergic urticaria, is basically an allergy to heat. It's not very sexy. In fact, it's basically prickly heat, something quite a few people struggle with in the summer. But my version is chronic. At my worst, any time my body generated or was engaged with heat, I'd come out in big red painful welts. Radiators were a no-no, similarly the sun, and movement became increasingly difficult. I was bed-bound for six months.

Almost nine years later, my condition has massively improved. From the 13 pills a day I was taking at my peak, I'm down to three; from two visits to hospital a week, I now barely attend at all. I can move, I can even dance (badly), I still can't drink, drive, swim or do aerobics, mornings remain quite tricky and I have reasonably regular attacks. But I am able to conduct a normal life within careful limitation. I am also an out, proud and accepted member of the disabled community. And I have slept with a few more women and remain disappointed at the demise of VHS.

Next week, Channel 4 will begin screening a comedy drama I co-created and co-wrote about my experience, and about the wider experience of disabled life. Cast Offs is about six disabled people who are put on an island by a reality TV show. But while in the skin of a mockumentary, it actually purports to do one very simple thing: tell disabled stories from a disabled perspective. In fact, our aim is to do for the disabled community what Queer as Folk did for the gay community. Having grown frustrated at the representation of disabled people on television, we've tried to explode a few myths.

At the centre of our show is Dan, representing me (albeit with the more attractive face of Peter Mitchell) and many other "born-agains" (do love that phrase). Six months in a chair after a car accident, Dan is adjusting to life as a disabled man. It scares the hell out of him. It's his dad who encourages him to join a wheelchair basketball team, it's his dad who gets him to apply for a reality TV show. Newly immersed in the world of disability, Dan discovers that not all disabled people are as introverted or full of self-hatred and pity as he. In the world of Cast Offs, blind men carry guns, wheelchair athletes stuff pants into postboxes and women with dwarfism talk about fisting far too much for their own good. Dan's coming-out story is all about that basic truth – a truth I learnt as he did: disabled people are just as annoying as non-disabled people.

It took a long time for me and my co-writers Tony Roche and Alex Bulmer to find the tone we wanted for the show. With two of the three of us being disabled (Alex is blind), writing for an exclusively disabled cast, we were anxious to avoid the obvious, but equally anxious to make something entertaining. We experimented with the broad and the tragic and in the end settled on wry comedy drama.

At the beginning of my TV career, I wrote on the series Shameless, a brilliant show created by Paul Abbott, about his childhood. The thing that I was fascinated to discover was that Paul had tried to write his childhood up before, but as a hard-hitting Ken Loach-style exercise in social realism. He hated what he produced, partly because he felt it wouldn't entertain anyone, partly because it didn't feel real. Two years later, he worked it out: his childhood – though in my many people's views bleak – was actually a comedy. But a real comedy based on real people in real situations. This was the phrase that lived in our hearts as we worked on the show: we wouldn't write slapstick and we would try to stay within the boundaries of real at all times, but rather than ask for pity, we'd ask for laughs.

Disablism remains a big prejudice in modern society. Last year on Jay Leno's primetime talk show, the President of the United States made a joke about disabled people which, if it had been about any other minority group, would have led to serious questioning of his ability to lead the country. Obama said that his performance at bowling was so bad "it was like the Special Olympics or something". Disability, by Obama's definition, was about difference and failure.

And TV buys into this prejudice; if it moved on from race discrimination in the 1970s, it's not moved on from disabled discrimination yet. I've grown bored of the number of shows I've had to turn off because the disabled person becomes a quirky object of pity – the nadir perhaps being the cringeworthy Britain's Missing Top Model, last year's BBC reality show where all the contestants were disabled.

And disabled actors themselves are frequently forced to take on parts which play with an identity they've grown to despise. Like Lenny Henry appearing on The Black and White Minstrel Show, they've had to accept that playing up to their lack of height or sight is the only way they can get work. Occasionally more interesting roles are written, but when they are, they're snapped up by the likes of Daniel Day-Lewis. And like Olivier playing Othello, these non-disabled actors win awards for this. As Kate Winslet memorably quipped on Ricky Gervais's comedy Extras, "You're guaranteed an Oscar if you play a mental." Doors are being knocked upon, but mostly in the wrong way by the wrong people.

That said, there are green shoots showing: disabled people are beginning to be cast in disabled parts and not have these parts be defined by their condition. Mainstream shows such as Hollyoaks, Shameless and EastEnders are bringing disabled actors in. More off-beat work is being done by the likes of the Graeae theatre company, by films such as Special People, which questions condescending outreach projects, Heavy Load, which follows a punk band with musicians who have learning disabilities, and The 8th Day, a French film starring a young man with Down's syndrome.

Things are slowly beginning to change. Cast Offs is part of that – the first TV series exclusively about the disabled experience. We are proud of that. But we're more than just "a Guardian reader's wet dream", as Gabby, one of our characters, describes herself. This has turned out to be one of the greatest creative experiences of my life. We're a filthy, funny, different TV show and I hope you give us a chance, because I think you'll like what you see.

'Cast Offs' begins on Tuesday and Wednesday at 11pm on Channel 4