The COVID-19 Vaccine does have some known side effects, which are very mild and typically last a few days. Serious side effects are extremely rare. Read more information about side effects in the sections below.

Side effects are important details that the MHRA always considers when assessing candidate vaccines for use.

All vaccines can cause mild-side effects like soreness around injection site – this is a sign that the vaccine is working.  But there is no way the Covid-19 vaccine can give you the illness, as it doesn’t contain any live virus.

These vaccines have a really good safety record – we wouldn’t be able to give them if they didn’t.

For this vaccine, like lots of others, they have identified that some people might feel slightly unwell, but they report that no significant side effects have been observed in the more than 43,000 people involved in trials.

All patients will be provided with information on the vaccine they have received, how to look out for any side effects, and what to do if they do occur, including reporting them to the MHRA.

Very common side effects include:

  • having a painful, heavy feeling and tenderness in the arm where you had your injection. This tends to be worst around 1-2 days after the vaccine
  • feeling tired
  • headache
  • general aches, or mild flu like symptoms
  • although feeling feverish is not uncommon for 2 to 3 days, a high temperature is unusual and may indicate you have COVID-19 or another infection

These symptoms normally last less than a week. 

You can take the normal dose of paracetamol (follow the advice on the packaging) and rest to help you feel better. Do not exceed the normal dose.

If you have a high temperature, you may have coronavirus or another infection.

If your symptoms get worse or you are worried, call 111.

Recently there have been reports of a very rare condition involving blood clots and unusual bleeding after vaccination. 

See vaccination and blood clotting

View Covid-19 leaflet AZ vaccination guide


We have heard anecdotal reports from some patients living with other conditions, that some of the side effects they have experienced mimicked the symptoms of their condition. 

In most cases, if you are feeling achey and sick, this is normal, and will subside when the side effects ware off. 

However, it is important that you let your GP know if you have a reaction that is not as described in the leaflet you will have been given or if your reaction was severe. Even if you do have symptoms after the first dose, you still need to have the second dose.  If you are worried, then please do contact your GP practice and discuss this with either the GP or one of the practice nurses.

So far, millions of people have been given a COVID-19 vaccine and reports of serious side effects, such as allergic reactions, have been very rare. No long-term complications have been reported.

Rollout of the vaccine in the UK started in December 2020, therefore specific long-term effects are unknown at this time. Even though people have begun to receive these vaccines, studies will continue to evaluate their safety and effectiveness long into the future. These studies will also focus on how long the immunity lasts from the vaccines.

If you hear something that concerns you, either about side effects or another topic, it is important that you look for information from a trusted and reliable source. Some articles and videos posted online are based on personal opinion, not scientific evidence, or expert advice. You can read more about the facts from the following sources online:

The NHS website website pharmacy pages

BBC News website

Recently there have been reports of a very rare condition involving blood clots and unusual bleeding after vaccination. This is being carefully reviewed but the risk factors for this condition are not yet clear.
Although this condition remains extremely rare, there appears to be a higher risk in people shortly after the first dose of the AstraZeneca (AZ) vaccine.
Around 4 people develop this condition for every million doses of AZ vaccine doses given.

This condition can also occur naturally, and clotting problems are a common complication of COVID-19 infection. An increased risk has not yet been seen after other COVID-19 vaccines but is being carefully monitored.

Currently, JCVI has advised that it is preferable for people under 30 to have a vaccine other than AZ. If you choose to have another COVID-19 vaccine you may have to wait to be protected. 

(Source: Public Health England)

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