A lack of resources and rising vacancy rates are putting too much pressure on NHS workers, doctors' leaders have warned.
A British Medical Association in Scotland survey found three quarters of its members believed their work had a negative impact on their own health.
It follows a recent nursing survey which criticised heavy workloads.
The Scottish government said the welfare of doctors was "paramount" and it was acting to improve conditions.
The BMA found 77% of the 800 respondents to its survey felt their work had harmed their health and wellbeing in the past year.
The study also found that 83% of those who responded saw their workload increase and 80% reported that they "often or always" worked beyond their time.
The BMA has called on the Scottish government to work with NHS boards across the country to improve conditions for medics.
BMA Scotland chairman Dr Lewis Morrison said: "Worryingly, our survey also found that two-thirds of doctors do not believe their employer provides sufficient support for staff wellbeing. This simply has to change.
"It is clear that caring for those who care for the people of Scotland must now be a priority. Now, next year and always."
Dr Morrison said the focus should be on funding and resources, rather than "treating the symptoms and not the cause".
He added: "Doctors' work will always be potentially stressful, but current conditions in the NHS simply aren't sustainable and, as a result, are creating unnecessary levels of pressure on all healthcare workers.
"We need a properly resourced system - and that means people, not just money. Simply saying again and again that we have record staffing doesn't cut it."
A Scottish government spokesman said: "The welfare of our hard-working doctors is paramount and we are committed to improving their working lives by taking action on issues that are important to them like pay, terms and conditions.
"We work closely with BMA Scotland to identify and implement changes all doctors want to see."
An independent expert group, established to make recommendations on further improvements, is due to report back by the end of the year and the health secretary will fully consider the recommendations.
The spokesman said a forthcoming independent report will build on changes already implemented at the request of junior doctors, including banning working seven consecutive night shifts.
Scottish Tory health spokesman Miles Briggs described the findings as a "stark reminder" of the pressures faced by medics.
He said: "Every day they are having to deal with huge workloads and long hours, and it's understandably having an effect on their health and wellbeing."