The Tánaiste says 2 million people could have boosters by the end of the year, due to the accelerated programme.
GPs will double the amount of extra doses they administer every week, and they can now accommodate all over-16s.
Vaccine centres will open from 8am to 8pm every day - and the 15-minute wait time after a jab has been scrapped.
Dr Denis McCauley, from the Irish Medical Organisation, says this will help GPs to give out 150,000 boosters a week.
"This 15 minute rule did curtail GPs quite a bit as it meant that they could only do as many vaccinations that would fit in their waiting room.
"Now we can proceed on a much quicker schedule and hopefully this will help us increase the numbers."
