Doctors earned more than €300 million in fees from the Government last year for services given to medical card holders, it has emerged.
GPs earned up to euro €560,000 under the scheme, a report due out later this week is expected to show.
Around 2,000 doctors, who operate the scheme, shared between them some €300 million in payments from the Department of Health.
The figures from the General Medical Services Payments Board will reveal later this week that more than 200 doctors were paid over euro €250,000 each, and seven over €400,000.
Last week, the Irish Medical Organisation confronted the Minister for Health Mr Martin over the Government's failure to extend medical card eligibility.
Mr Martin had agreed the threshold for the service was too low.
He said the Government had been trying to examine the scheme with the IMO but the group would not consider negotiating issues such as fees.
The money paid for medical card services was calculated per practice, where there may be a several GPs working and the surgery's expenses are also taken out of the fees.