The teacher, who lives in the West Midlands and has not yet been named, will resign this month on the grounds of stress- related illness, which he claims was the result of overwork caused by Mr Patten's education reforms.
He says he is very angry at the way in which the Government's actions have brought about his condition and the National Union of Teachers is considering whether to back him in legal action against Mr Patten.
Figures to be released tomorrow by the Labour Party illustrate that he is not alone. The number of teachers retiring on health grounds has more than doubled in 10 years,
from 2,500 in 1984 to 5,500 last year.
If the teacher's legal action were to succeed, it could open prompt thousands of similar cases in which former teachers claimed damages for the effects of their increasing workload, much of which is administrative paperwork.
Teachers' unions say the National Curriculum and other reforms have caused a dramatic rise in stress levels, leading to illness, breakdown and demoralisation.
Brian Clegg, salaries and pensions officer for the second biggest teachers' union, the National Association of Schoolmasters Union of Women Teachers, said there had been hopes two years ago of a drop in retirements through ill health, but they had not been fulfilled.
Fewer teachers were now leaving the profession at the normal retirement age than those taking early retirement or those leaving through ill health, Mr Clegg said.
'It says an awful lot about the way teachers now view the job,' he commented. 'Teaching is fine, it is the rest of the Government's initiatives that matter.'
Ann Taylor, Labour's education spokeswoman, said the loss was costing the Government pounds 130m a year. The average lump sum paid to such teachers is pounds 23,700 and the average pension is pounds 8,000 per year.
Mrs Taylor said the education system could ill afford to waste its resources in this way. 'Everyone knows that the constant chopping and changing has put enormous stress on to teachers.
'Education is losing some of its best teachers because their health reaches breaking point when they cannot deliver education to the high standards they set themselves.'
Few teachers can consider themselves immune from the effects of stress. Jenny Goold, head teacher of Blurton Primary School in Stoke-on-Trent, gives training courses to fellow teachers on coping with stress, but could not recognise it in herself.
She was away from school for a whole term with stress-related illness earlier this year, and two members of her 15- strong staff are currently absent with similar conditions. One of them will take retirement this summer as a result of her condition.
Ms Goold went to her doctor with a rash and was told that her condition was caused by overwork. She was putting in up to 70 hours a week, but now insists on making some time for herself and her family.
'It came as an enormous shock to me when the doctor told me that was what it was,' Ms Goold said. 'It is quite easy to see in others but it is quite difficult to see in yourself.'
A headteacher for 14 years, she says the workload has increased dramatically since she took up her job. She now pins her hopes on the current slimming down of the National Curriculum.
'We just cannot keep pace with the change no matter how hard we try. We have an extremely hard-working and conscientious staff here and we have never been in this position before.
'We are demoralised because we can't get to where we want to be. We just want to get the curriculum under control.'Reuse content