The HSE has confirmed the majority of AstraZeneca clinics have been cancelled for the rest of the week.
However, it says a small number will continue for certain people over the age of 60.
It follows NIAC's recommendation that the vaccine be used for people in their 60s only, due to rare blood clotting.
Meanwhile the roll-out of the Johnson and Johnson vaccine to Ireland has been delayed as the company examines reports of rare blood clots.
Use of the jab was suspended in the US as they examine 6 cases among the 6.8 million doses already given.