The Department of Social Protection is paying GPs and other certifying doctors almost €500,000 a week for completing and signing medical certificates.
Under the Illness Benefit scheme, doctors get paid €8.25 from the State for each certificate they sign for people who are out of work for more than three days. This is separate to patient consultation fees.
The information was obtained through parliamentary and follow-up questions from Labour's Kevin Humphreys, who said doctors were coining it for a service that he believed they were already paid for.
He added that the fees were ridiculous and the Government could not afford them.
This evening, the Irish Medical Organisation said that certifying patients makes up a large proportion of GPs' work and that the fees had been reviewed on two separate occasions and had not increased since they were negotiated in 2003/4.
They also said that GPs had been subject to two rounds of public service cuts and the fees were also covered by the Croke Park Agreement.
Employees who are sick and out of work for more than three days can apply for Illness Benefit. Following a medical examination, they must get a GP or hospital intern who is eligible to complete and sign a Medical Certificate 1 form (MC1).
The employee or their employer can then claim illness benefit payment from the Department of Social Protection. If the illness persists, the doctor will sign a Medical Certificate 2 form (MC2) on a weekly basis.
The Department says this should only be signed on foot of medical exam. The IMO says this doctors who are examining patients for the sole purpose of providing a MC2 do not charge the patient fees.
Every time both of these forms are completed the Department pays the doctors get paid €8.25.
On average, 5,000 MC1 and 50,000 MC2 forms are completed every week.
In total, the State is paying GPs more than €450,000 a week and more than €23m a year for completing these forms.
The highest payment for this last year was €83,000 euro and was paid to a practice with 13 doctors.
The 2,800 participating doctors are paid an average of €10,000 each a year.