Taoiseach Bertie Ahern criticised pharmacists for withdrawing services from methadone patients in a dispute with the HSE.
He said while disputes had to be resolved by negotiation, there was no justification for bringing recovering drug addicts into a dispute irrespective of whether it was of a commercial or industrial relations nature.
"The dispute has nothing to do with people who are doing their best to recover from an addiction problem. The HSE has stated that there is a significant clinical risk to clients who revert from a methadone maintenance programme to opiate use.
"In the light of this, the action of 140 pharmacists to withdraw services from approximately 3,000 methadone patients is totally wrong, and the same applies to threats to withdraw from dispensing drugs to medical card holders."
Mr Ahern said it should be noted this was not an act of the Irish Pharmaceutical Union, "and I ask those who are doing this to drug addicts to stop immediately".
Drug addicts had nothing to do with the dispute. The dispute centred on the price of drugs which pharmacists dispensed and for which they were reimbursed. The HSE had set a new price which, because of competition law, could not be negotiated.
Expressing disappointment with the pharmacists' decision, Minister for Health Mary Harney said she understood that the Competition Authority was examining whether their action might be in breach of competition law.
She said there was a significant clinical risk of overdose to patients who reverted from a methadone maintenance programme to opiate use.
In those circumstances, the HSE had developed a contingency plan to ensure continuity of service and to minimise any hardship to patients.
Labour leader Eamon Gilmore said those affected by the dispute were, in the main, recovering heroin addicts getting their lives together.
"The withdrawal of this service has thrown them back into the ad-hoc arrangement of drug-treatment clinics which brings them back into the same type of environment and company which may have been responsible for their problems in the first instance."
Fine Gael health spokesman Dr James Reilly said: "I do not condone the action of pharmacists in putting patients at risk although, like many members, I recognise their frustration with the HSE."
