Minister for Health James Reilly has said that people who have a medical card and are entitled to it have nothing to fear about losing it.
He was speaking to reporters following concerns about the reduced eligibility for medical cards for people over 70 and a reduction in discretionary medical cards.
The cuts and a lower income threshold meaning fewer over-70s will be eligible were announced in the Budget.
Mr Reilly said a discretionary medical card was given on the basis of financial hardship and not on the basis of illness.
He said the number of discretionary medical cards provided has dropped by about 24,000 since 2009.
But nearly all of those people received a full medical card, the minister added.
Mr Reilly said he has asked the Health Service Executive to draw up a communications plan involving commercials, radio and television so the public could be fully informed as to what is happening about medical cards.
He said HSE letters that were sometimes unclear could cause fear among elderly people.
"In many cases all we're doing is just checking that person is still in the country or still alive," the minister said.
"I want to give a very strong message. People who have a medical card and are entitled to it have nothing to fear.
"They are not going to lose their card and that's really important to emphasise."
The minister added that the Government was trying to bring fairness into the health system and that he was concerned about the practice around the country that led to inequity in terms of who got a medical card and who did not.
He said that even if everyone had free GP care here, it would not end the inequitable two-tier system whereby those with money are seen first.
Concern over discretionary medical cards
Meanwhile, a senior figure in the National Association of General Practitioners has said he believes there have been changes in how discretionary medical cards are awarded.
Speaking on RTÉ's Today with Sean O'Rourke programme, Dr Andy Jordan said fellow GPs have been experiencing patients who are losing their discretionary medical cards without warning.
"Every doctor has a number of cases of patients with cards being deleted off the system," he said.
He said there is no doubt that there seems to have been a change either operationally or in policy that has led to a sudden change in the number of people losing discretionary cards in particular.
Speaking at an Oireachtas committee yesterday, HSE Director General Tony O'Brien said there has been no change in eligibility criteria for discretionary medical cards.