The Irish Blood Transfusion Service is urgently looking for donations.
It needs an extra 2,000 blood donations over the next four weeks to support the national supply.
Appointments for clinics in the city, Bantry, Skibbereen, Blarney, Ballincollig and Kanturk for the next month can be booked by calling 1800 731 137.
Director of Operations, Paul McKinney says, in August, they issued the highest amount of blood units to hospitals in over a decade - but demand has continued:
"Across all groups, is extremely low. It's under three days for O negative, which is the universal blood group, a negative, B negative. And worryingly it is below 3 and a half days for O positive, which over half of the Irish population are."
