A new electronic form will replace the Med 3 and Med 5 forms, and allow GPs the option to advise a patient that they 'may be fit for work'.
The GP would then be able to suggest ways that the patient could be helped to return to work sooner, for example with shorter hours or adaptations to the workplace.
The RCGP has been running courses on work and health issues to prepare practices for the changes and so far around 1,000 GPs have attended.
RCGP chairman Professor Steve Field welcomed the new Med 3 form, which he said allowed GPs to make a positive intervention and prevent their patients from slipping in to long-term sick leave and developing further health problems.
Professor Field, speaking exclusively in a Healthcare Republic podcast to explain the new system, said: 'The changes will be good for patients and will be very good for GPs as well. But this is not a change in isolation, it's an important shift for society as a whole.
'We will move from the very black and white system of being sick or not sick and instead see what we can do to help them get back to work.'
According to the Department of Work and Pensions, every year an estimated 350,000 people leave work to claim health-related benefits and around 172 million working days are lost in Britain each year due to sickness absence.
- Listen to RCGP chairman Professor Steve Field explain the changes to the sick note system in our exclusive Healthcare Republic podcast.