Vaccines are the most effective way to prevent infectious diseases. They prepare your immune system (your body's natural defences) to recognise and defend itself against a specific virus.
The Pfizer/BioNTech COVID-19 vaccine is safe and effective.
You will need 2 doses of the Pfizer/BioNTech COVID-19 vaccine.
It takes 7 days after the 2nd dose for the Pfizer/BioNTech COVID-19 vaccine to work. This is when you are fully vaccinated.
You should get your 2nd dose 4 weeks (28 days) after your 1st dose.
Vaccines teach your immune system how to protect you from diseases.
It is much safer for your immune system to learn how to protect you from COVID-19 through vaccination than by catching the virus.
The Pfizer/BioNTech COVID-19 vaccine was developed in line with international standards of safety.
Millions of people in the UK and the US have been given the Pfizer/BioNTech COVID-19 vaccine.
Like all medicines, vaccines can cause side effects. Most of these are mild to moderate and short-term.
Not everyone gets side effects.
Which vaccine is best
All vaccines are tested for safety and effectiveness before they can be used. The HSE only uses a vaccine if it meets the required standards of safety and effectiveness. You should get any vaccine that is offered to you.
If you are pregnant
There’s no evidence that COVID-19 vaccination is unsafe if you’re pregnant. Being vaccinated will reduce the chance of you becoming very unwell.
The information we have so far shows that the Pfizer/BioNTech COVID-19 vaccine does not have any negative effect on babies in the womb.
If you are breastfeeding
There is no known reason to avoid breastfeeding if you are vaccinated.
If very small parts of the vaccine get into your breast milk, they will be digested in your baby’s stomach.
This content was fact checked by vaccine experts working in Ireland
Last updated: 6 May 2021 at 5.50pm