Despite having wanted to be a teacher since he was a teenager, the 38-year-old left the profession two years ago because he could no longer cope with the pressure.

He is now studying sociology at a local college, and says he feels "nothing but sympathy" for his former colleagues.

"Many of them feel isolated and dispirited and frankly, unable to cope," he said.

John was teaching in a mixed comprehensive school in Manchester when the pressures of his work started piling up.

'Terror inside'

"For the first six years I really enjoyed the work, and although the pupils came from reasonably poor backgrounds, they were a great bunch of children.

"My fiancée and I had married and bought a house, which we were doing up, and life was good.

"But then I found my job responsiblities were increasing, preparing for the Ofsted inspection took months, concerns about exam results, syllabus changes and implementing the national curriculum were always at the forefront of my mind.

"I kept up a professional front in the classroom, but I was only masking the terror I felt inside.

"At first I didn't realise how much work was affecting my life. Increasingly, I found I couldn't switch off when I came home.

Panic attacks

"If I wasn't snapping at my wife, I was quiet and withdrawn. I started not wanting to socialise, I became indecisive and nervous about meeting strangers.

"I found myself dreading going into work on a Monday morning to the extent that I would suffer panic attacks throughout the weekend.

"After 18 months of feeling like this I woke up one morning and literally couldn't get out of bed. My wife persuaded me to go and see my GP who said I had had a complete nervous breakdown. After five months off sick I finally made the decision to leave teaching.

"Considering the vital role teachers play in children's lives, it is vital they are given the support they need."

The freephone Teacherline number is 08000 562561.