Ten per cent of teachers have been prescribed anti-depressants because of the stress of the job, research by a teaching union has found.

The survey of more than 5,000 teachers, carried out by the NASUWT union, also found 47 per cent had seen a doctor because of work-related physical or mental health problems in the past 12 months.

It found teachers were turning to medication, alcohol, tobacco and caffeine to help them cope with the demands of the job.

Twenty two per cent said they were increasingly using alcohol to cope with work-related stress, 21 per cent said they were consuming more caffeine and five per cent were smoking more as a result of stress.

Seven per cent had increased their reliance on prescription drugs because of the demands of the job.

Fourteen per cent had received counselling and five per cent had been admitted to hospital, it found.

One teacher responding to the survey said: “Suffering anxiety and stress. Currently taking anti-depressants to overcome depression, brought on by the pressures of the workload and job.”

Another said they were “overly tired, [with] poor sleep patterns, no quality time with family, constant worry [and a] heavy work load [of] 70-80 hours per week.” This was making them “irritable and less patient.”

A motion to be discussed at the NASUWT’s annual conference in Birmingham this weekend says members are “deeply concerned” about teachers’ wellbeing.

“Excessive workload and working hours are having a damaging effect on teachers’ mental and physical health and wellbeing and leading some teachers to self-medicate and self-harm,” it says.

Chris Keates, general secretary of the NASUWT, said the figures were “shocking”.

“Instead of offering support, in far too many cases we see employers introducing punitive and callous sickness absence policies,” she said.

“High quality education cannot be delivered by stressed and anxious teachers.”

A Department for Education spokesperson said: "We know unnecessary workload is one of the biggest frustrations for teachers.

"We are working with the profession and education experts to take action on the root causes of teacher workload, including through the first biennial teacher workload survey and looking in depth at the biggest concerns teachers have raised - marking, planning and resources and data management."

"We trust heads, governors and academy trusts to plan their staffing and make sure teachers and staff have the support they need."