More than two thirds say their job prevents them from giving adequate time to their partner, family and friends and more than half say their significant others get fed-up with the pressures that teaching puts on their relationship.
While more than four out five teachers say that they frequently worry about work problems when they are not working and just 11 per cent say they are able to relax at home.
More than half say their job satisfaction has declined in the last 12 months, according to the report, with almost 60 per cent saying their job has adversely impacted on their mental and physical health in the last year.
Chris Keates, general secretary of the NASUWT, said: “It is clear that for too many teachers the job is taking an unacceptable toll on their health and wellbeing and that this is affecting all aspects of their personal and professional lives.
“If the majority of teachers are unable to relax away from work and feel constantly worn down and worried about work issues then their mental and physical health is inevitably going to suffer and they will not be able to give their best to the children they teach.
“Teachers are often made to feel that they are failing if they admit to experiencing stress, exhaustion or health problems in the workplace, yet concealing the problem inevitably makes it worse. Employers have responsibility for the mental health and wellbeing of their staff, but few address this seriously.”
Teachers report turning to medication, alcohol, tobacco and caffeine to help them cope with their job, with 22 per cent reporting an increased use of alcohol and caffeine and five per cent revealing they smoke to help them manage work-related stress.
More than 10 per cent say they have undergone counselling, seven per cent have used or increased their reliance on prescription drugs and 11 per cent rely more heavily on anti-depressants to help them cope.
Four per cent have been admitted to hospital as a result of work-related illness, and two per cent say they have self-harmed as a result of work-related stress.
The pressures of teaching are also sapping teachers of their morale and energy, with 83 per cent saying their job has had an adverse impact on their wellbeing.
More than half say they do not look forward to going to work and the same number say they are often too worn down to give their job their best effort. More than 80 per cent say they are too tired after work to do things they enjoy and only eight per cent say they have the time and energy for hobbies.