Imagine not being able to take a single step outside your own front door without being gripped by fear.
Rooted to the spot and unable to even tie his shoelaces – that was the situation Adrian Mundy found himself in when his agoraphobia began.
A panic attack 11 years ago was the start of Adrian's phobia and, like many other sufferers of the condition, he found himself shut off from the rest of the world as his fear of venturing out only grew.
Adrian has never left England, he finds public transport impossible to use and for eight years he wouldn't even travel beyond Portsea island.
At its very worst, he couldn't leave the Southsea street he lives in for more than two months.
People often think of agoraphobia as a fear of open spaces, but in fact it is an anxiety disorder, which sees sufferers worry about having a panic attack in a setting where there will be no easy means of escape.
'For me it's a social thing,' explains Adrian. 'I feel like everyone's watching me and I just want to hide.
'I might be in Tesco and suddenly I'll feel panic rising and the need to get out immediately, but I know I can't because that would be a step back.
'When I'm in isolation I have a flatline of emotion, but when I go out I have a high which means I have a low when I am home again.
'The more I get out, the higher I get, the further the drop to the low.'
Adrian believes his agoraphobia was partly triggered by ME – also known as chronic fatigue syndrome.
He was diagnosed with ME 21 years ago, after he collapsed six weeks into sixth form college.
'I went on to attend Portsmouth Art College and got through it, with the help of my mum and lecturers, who would drive me to and from campus,' he gratefully explains.
'I looked into studying model making in St Albans, but I could never have coped on my own. I couldn't go into full-time employment. I was too exhausted. I had a Saturday job but couldn't work the whole day.'
He adds: 'When my ME was at it's worst I couldn't leave the house and eventually I spent so much time indoors that my muscles wasted away and I lost the confidence to face the outside world. My life virtually stopped.'
The 38-year-old continues: 'I went to my sister's house for Christmas 11 years ago and I felt funny. I now know that was a panic attack.
'I made a doctor's appointment, but when it came to going, I couldn't step out of the front door. I had another panic attack just trying to tie my shoe laces because of the thought of having to go out.
'So the doctor came for a home visit and diagnosed me with agoraphobia.'
Adrian's turning point came a year ago when, determined to see the first exhibition of his own work on display at Havant Arts Centre, he made a momentous journey to the town. And now he's insistent that there will be no looking back.
He's gained the confidence to take further steps to overcome his agoraphobia and rents a studio at Art Space Portsmouth, leaving his house two or three times a week and travelling there on an electric bike.
His condition has even inspired his new work – currently on display at Portsmouth's gASP Gallery, and at Aspex, at Gunwharf Quays.
Adrian has used words written by or about people, places and events connected to agoraphobia as he emerges into the outside world.
And he's bravely spoken out about his phobia to raise awareness of the condition because he wants people who take their freedom for granted to understand how a simple trip to the supermarket can be such a triumph.
Where once he was confined to his home, he now dreams of visiting London, thanks to his art.
'The studio environment has sped-up my creative process,' he beams.
'It's an exciting time for me. I've worked hard to get here and now I just have to make the final step out into the big wide world.'
Sudoku was inspiration for 'random' works of art
Adrian calls his unique style of painting 'pre-determined randomness'.
'I was doing a sudoku puzzle and wondered what would happen if you changed the numbers to colours,' he explains.
'I moved on to crosswords and word searches and eventually to using my own grids and my own words.'
On one sheet he draws a grid which may be manipulated into a 3D shape and writes a word on it with a letter in each space. On another sheet he makes a note of which colour he has assigned to each letter and then the actual painting of acrylic on canvas begins. There are no computers involved in the process.
Check out Adrian's latest exhibition, Unique, for free at gASP Gallery Art Space Portsmouth, 27 Brougham Road, until March 21.
Adrian will also be holding a Meet the Artist session this Saturday from midday until 2pm.
Agoraphobia leaves sufferers exposed
While many people think agoraphobia is the word used to describe an intense fear of open spaces the reality of the condition is much more complex.
The World Health Organisation defines agoraphobia as a cluster of phobias, or irrational fears, related to leaving home, entering shops, being in crowds and public places, or travelling alone on buses, trains or planes.
It is in these situations that the sufferer is likely to feel especially vulnerable and exposed, with nowhere to escape to or hide, if things go wrong.
The degree of fear depends on the sufferer and while many agoraphobics do go out to work, some become completely housebound.
It's common for sufferers to feel anxious, depressed and experience panic attacks, and many avoid coming into contact with other people altogether.
Unless the condition is treated it can go on for many years, totally affecting the way a person leads their life.
The phobia affects one person in 20 at some stage in their lives and modern treatments include short exposures to public spaces one step at a time.
Famous sufferers, including Hollywood stars Woody Allen and Kim Basinger, have talked about their experiences of the condition in the past.
>>> For more information or support check out anxietyuk.org.uk or call 08444 775 774.