Patients being treated by burned-out doctors may face additional risks when they receive care.
A new study by the University of Manchester concluded that doctors experiencing burnout are twice as likely to be involved in patient safety incidents such as medication errors and "suboptimal care".
The link between burnout and patient safety incidents was highest among younger doctors and emergency medicine physicians.
The study, published in the BMJ, comes as senior health leaders in the UK have raised serious concerns over burnout among doctors working in the NHS.
On the back of dealing with the Covid-19 pandemic, doctors are now facing record waiting lists in hospitals while GPs try to keep waiting patients well in the community.
Even before the pandemic doctors were dealing with rising demand and increasingly complex cases as patients live longer, many with multiple health conditions.
And a damning report from the influential Health and Social Committee of the House of Commons, published last summer, found NHS and social care staff burnout has reached an "emergency" level and poses a risk to the future of services.
Burnout is defined as a syndrome related to emotional exhaustion, a sense of reduced personal accomplishment, and a sense of cynicism and "detachment" from work.
The new study, led by academics at the University of Manchester, set out to examine the effects of burnout on a global scale.
They conducted a systematic review of all available research on doctor burnout.
They analysed statistics from 170 studies, involving more than 239,000 doctors, and found:
Burnout was linked to an almost four-fold decrease in job satisfaction and medics were more likely to regret their career choice.
They were more than three times as likely to have thoughts or intentions to leave their job.
Overall physician burnout doubled patient safety incidents.
The association between burnout and patient safety incidents was greatest in physicians aged 20-30 and people working in emergency medicine.
As burnout increased, low professionalism was twice as likely, as was patient dissatisfaction.
Burnout and poorer job satisfaction was greatest in hospital settings, among doctors aged 31-50 and among those working in emergency medicine and intensive care.
The authors concluded: "Burnout is a strong predictor for career disengagement in physicians as well as for patient care.
"Moving forward, investment strategies to monitor and improve physician burnout are needed as a means of retaining the healthcare workforce and improving the quality of patient care."