BMA Northern Ireland has taken a 32,000 signature petition against primary care funding cuts to health minister Michael McGimpsey at Stormont.
With practices facing cuts of up to £50,000 to their core funding, GPs say they may have to stop providing some services to keep other treatments available.
As well as shedding staff, the BMA said practices may have to close diabetes, counselling and physiotherapy clinics.
Around £5m was cut from enhanced service and locum funding in Northern Ireland in 2010/11, leaving the average practice around £15,000 out of pocket. The Department for Health, Social Services and Public Safety withdrew the funding in the middle of the financial year, after practices had set their budgets.
Dr Brian Dunn, chairman of GPC Northern Ireland, said GPs were feeling 'totally overwhelmed' by the cuts.
'The tens of thousands of patients who have signed our petition clearly see the need for a properly resourced general practice service,' Dr Dunn said.
'Regrettably our local decision makers do not seem to appreciate the service that they have.'