The Health Service Executive has said it may take weeks to clear delays in chemotherapy treatment caused by a shortage of a specific drug to treat cancer.

A number of cancer patients have suffered delays in chemotherapy treatment due to the shortage.

Some chemotherapy drugs were recalled two weeks ago, as a precautionary measure, following fears they may have been contaminated during manufacturing.

Dublin-based pharmacy Fannin Compounding, one of two companies supplying chemotherapy drugs to Irish hospitals, issued a safety alert after a machine it uses to manufacture the medicine was found to have been contaminated.

The bacteria, which can cause potentially life-threatening gastro-intestinal infections, was found in batches of drugs during routine testing.

In a statement this morning, the HSE said some hospitals throughout the country are currently experiencing difficulties in securing continuous supply of chemotherapy drugs due to the safety alert at Fannin Compounding.

The HSE would not give any details of the number of people affected by the shortage of the drug due to the contamination, but said that it was a "sub-set of cancer patients".

Five patients who are treated at Our Lady of Lourdes Hospital Drogheda had their treatment postponed from Tuesday to Wednesday last week.

Delays of one or two days for the cancer treatment have been experienced at Cavan Hospital, while University Hospital Limerick has also confirmed that eight patients have been rescheduled for treatment next week due to a delay in receiving supplies. 

The HSE moved to assure patients that hospitals are in contact with those affected to reschedule their appointments.

The HSE's contingency plans to deal with this issue involve sending some cancer sufferers to different hospitals for treatment and sourcing the drug from another company in Ireland as well as the United Kingdom.

It says this is a temporary solution until operations resume at Fannin Compounding.

The HSE also said the precautionary recall has been completed.

It said: "There was no evidence of contamination of chemotherapy and, more importantly, no evidence of adverse clinical consequences for patients."