Stressed teachers are suffering depression and even considering suicide due to heavy workloads, naughty pupils and a "tick-box culture" in schools, research suggested yesterday.

It reveals that school staff are suffering from a range of stress-related problems including heart palpitations, sleeplessness, depression and eating problems, the survey, commissioned by the NASUWT teaching union, claims.

The report, based on interviews with teachers and school managers, concludes that the pressures of inspections and school accountability have a "profound impact on teachers' work and on the quality of their working lives".

Targets, a tick-box culture, large classes, unruly students and bullying are among the causes of stress, the report, by Compass Centre for Mental Health Research and Policy, found.

Among the other stress symptoms teachers reported were agoraphobia, difficulty concentrating, nightmares and thoughts of suicide.

The study says: "There is a strong suggestion that schools do not have the systems and processes needed to identify and intervene at an early stage when a teacher's mental health condition is at risk of deteriorating.

"Indeed, school leaders may be under pressure not to invest much of their energy or time in supporting teachers who have mental health problems because of the perceived costs to the school and in order to protect their own personal well-being.

"In short, teachers who are already vulnerable are denied support from the school, their manager and from the system as a whole."

NASUWT general secretary Chris Keates said: "Teaching is widely recognised as one of the most stressful occupations, but a healthy workforce is central to delivering healthy outcomes for pupils.

"The research commissioned by the NASUWT highlights the need for access to support, counselling and specific health interventions for the workforce."