The Irish Cancer Society says it is worried some cancer patients may stop getting treatment - because many hospitals are now charging €75 for each round of chemotherapy.
The patients affected are those who don't qualify for a medical card and who don't have health insurance.
The news comes as new figures show that applications to the Irish Cancer Society's financial aid scheme increased by 36% in the past three years and now accounts for an annual spend of more than €1m.
Head of Advocacy and Communications with the ICS, Kathleen O'Meara, said: "Yes we have concerns that there may be people who are under pressure and may not feel like they can afford the €75.
"We want them to go for their treatment but we have concerns that over this charge they might think twice about it. We certainly hope that won't happen."