The HSE appears to have reversed a decision to axe medical funding to narcolepsy sufferers who are suing the state over their condition.
The families involved claim they developed the sleeping disorder from a swine flu vaccination.
Support group SOUND says around 60 people in Ireland have been affected.
The High Court has heard that two students legally challenging the withdrawal of funding received a letter from the HSE this afternoon which appears to confirm the reinstatement of all entitlements.
In a statement, the State Claims Agency said that it told the HSE it should stop making out of pocket payments to individuals who were suing the State, but it did not advise it to alter its approach to items like medical cards or other health benefits and supports.
SOUND spokesperson Mary FitzPatrick says the HSE must prove its commitment by paying the claims quickly.
"Not everyone had claims in for expenses, but some of them did - and we want them now to prove that this is what they're going to do, that they have reversed this decision and we want those expenses paid by Friday of this week," she said.