An expert panel set up on foot of a Government decision has concluded it is not possible to identify a list of medical conditions to be considered when determining a person's eligibility for a medical card.
The unpublished 70-page report, seen by RTÉ News, has found that it would be "neither feasible nor desirable" to list medical conditions that would qualify in order of priority.
The 23-member panel was unable to devise the list because of the range of illnesses that exist and the varying degrees of severity within each category of illness.
Some members on the panel had never heard of some of the conditions raised in more than 2,000 public submissions received.
It said that any reform should be introduced as part of the process of free GP care for all.
The panel was set up by the Health Service Executive following major public and political controversy over the removal of discretionary medical cards over the past year.
The report found that the existing discretionary card system works but it is imperfect and it has recommended changes.
The panel said the system for granting discretionary medical cards is not efficient and the rules are not applied uniformly around Ireland.
It also found many cases where applicants for a discretionary card received no response after their application was submitted.
The report has called for a consistent approach to the system.
Peter Fitzgerald, of Our Children's Health, echoed this recommendation saying the current medical card system amounts to "a rigorous financial audit" of very sick people.
Speaking on RTÉ's Six One, Mr Fitzgerald said that he hears of new cases every week, of children with serious medical illnesses, who do not qualify for a medical card.
He said such families are incurring a myriad of unknown costs that are not covered by the Drugs Payment Scheme.
Mr Fitzgerald acknowledged the difficulty the expert panel had in coming to its conclusion and conceded that it is not possible to decide who qualifies on the basis of a list of illnesses.
Mr Fitzgerald said if clear criteria was outlined it would strengthen the system for medical card distribution.
"...for example, somebody who is unable to work, who is unable to participate in education, who has an expected number of hospital visits every year...would qualify for a medical card."
The Cabinet Committee on Health directed that the panel be set up by the HSE in the wake of the controversy over the removal of discretionary medical cards, many of which were later returned.
It was chaired by Professor Frank Keane, past president of the Royal College of Surgeons in Ireland, and it was asked to report to the HSE Director General.
In May, the HSE's review of discretionary medical cards was suspended and it committed to returning 15,300 cards.
It followed heavy criticism of the Government and widespread reports of people with long-term medical conditions losing their cards, some in the case of sick children.
The controversy was one of the biggest issues on the doorsteps for politicians in the lead-up to the Local and European Elections.
Campaign groups have been lobbying for people with certain conditions and sick children to be granted discretionary medical cards.
The existing medical card scheme is based on the Health Act 1970 and medical cards are issued based on financial means.
The HSE can exercise discretion where an applicant is over the income eligibility levels but has social or medical issues that cause undue financial hardship.