Side effects of the coronavirus vaccines

Like all medicines, vaccines can cause side effects. It’s normal to experience side effects after the vaccine. It shows the vaccine is teaching your body’s immune system how to protect itself from the disease. Not everyone gets side effects. Most side effects are mild and normally last only a day or two.

Side effects of the coronavirus (COVID-19) vaccination

Very common side effects in the first day or two include:

  • having a painful, heavy feeling and tenderness in the arm where you had your injection
  • feeling tired
  • headache, aches and chills
  • diarrhoea, nausea and vomiting
  • mild flu-like symptoms

These common side effects are much less serious than developing coronavirus or complications associated with coronavirus. They usually go away within a few days.

If you feel uncomfortable, you can rest and take paracetamol. Make sure you take paracetamol as directed on the label or leaflet. Remember, do not take medicines that contain aspirin if you're under 16 years of age.

If your side effects seem to get worse or if you're concerned, phone NHS 24 free on 111. Tell them about your vaccination so that they can assess you properly.

Fever after the coronavirus vaccine

It’s quite common to develop a fever (temperature above 37.8C) after a vaccination. This normally happens within 48 hours of the vaccination and usually goes away within 48 hours. This is an expected reaction.

If the fever starts more than 48 hours after the vaccination, or lasts longer than 48 hours, you should seek medical advice as you may have coronavirus or another infection.

Side effects for each dose

Not all coronavirus vaccines are the same. Some tend to cause more side effects after the first dose, others cause more side effects after additional doses. The very common side effects are the same and should still only last a day or two.

Even if you do have side effects after the vaccine, NHS Scotland advises you get all recommended doses. The full recommended course will give you the best protection against the virus.

Waiting time after your coronavirus vaccination

As long as you feel ok, you should only stay for 5 minutes after your coronavirus vaccination.

Make sure you tell the vaccination staff if you have:

  • a history of allergies, particularly to other vaccines
  • had an immediate reaction after your previous doses
  • previously fainted following vaccination

In these circumstances, you may be advised to stay for 15 minutes. A family history of allergies (or even anaphylaxis) is not a risk factor.

You must not drive for 15 minutes after the vaccine because of the risk of fainting.

If you experience symptoms of an allergic reaction, call out for help and/or phone 999 immediately (or ask someone to do this for you). Symptoms usually happen within 15 minutes of vaccination.

You should look out for the following allergic symptoms:

  • persistent cough
  • vocal changes (hoarse voice)
  • swollen tongue causing difficulty swallowing
  • difficult or noisy breathing
  • wheezing (like an asthma attack)
  • feeling lightheaded or prolonged faint
  • clammy skin
  • confusion
  • unresponsive or unconscious

Less common side effects

If you had serious side effects after any previous dose, you may be advised to avoid or delay further vaccination. You should discuss this with your health professional.

Swollen glands in the armpit or neck

An uncommon side effect is swollen glands in the armpit or neck, on the same side as the arm where you had the vaccine. This can last for around 10 days. If it lasts longer, speak to your health professional.

If you are due for breast screening (a mammogram) then you should mention that you have had the vaccine when you attend.

Heart inflammation

Worldwide, there have also been recent, rare cases of inflammation of the heart called myocarditis or pericarditis reported after coronavirus vaccines. However, it's not yet clear that these are caused by the vaccines.

Most of these cases have been in younger men and usually happen a few days after vaccination. Most of these people recovered and felt better following rest and simple treatments. Longer term follow-up is ongoing in the UK and elsewhere to better understand this reaction.

You should seek medical advice urgently if you experience:

  • chest pain
  • shortness of breath
  • feelings of having a fast-beating, fluttering, or pounding heart

Reports of very rare blood clots

The Medicines and Healthcare products Regulatory Agency (MHRA) is carrying out a detailed review of reports of a very rare blood clotting problem affecting a small number of people who have had the Oxford/AstraZeneca vaccine.

The problem can also happen in people who have not been vaccinated and it's not yet clear why it affects some people.

The current reported rate of this condition in the UK is around 15 cases per million first doses given.

The coronavirus vaccine can help stop you from getting seriously ill or dying from coronavirus. For people aged 40 or over and those with underlying health conditions, the benefits of being vaccinated outweigh any risk of clotting problems.

For people under 40, it's currently advised that it's preferable to have either the Pfizer/BioNTech or Moderna coronavirus vaccine.

If you have already had a first dose of the Oxford/AstraZeneca vaccine without suffering any serious side effects you should complete the course (unless there is a medical reason for you not to have the same vaccine).

This includes people aged 18 to 39 years who are health and social care workers, unpaid carers and those who live with someone with a severely weakened immune system.

Urgent advice: Speak to your GP if:

You get any of these symptoms starting from around 4 days to 4 weeks after being vaccinated:

  • a severe headache that is not relieved with painkillers or is getting worse
  • a headache that feels worse when you lie down or bend over
  • a headache that's unusual for you and occurs with blurred vision, feeling or being sick, problems speaking, weakness, drowsiness or seizures (fits)
  • a rash that looks like small bruises or bleeding under the skin
  • shortness of breath, chest pain, leg swelling or persistent abdominal (tummy) pain

If your GP is closed, phone 111.

Oxford/AstraZeneca COVID-19 vaccine and rare blood clots information leaflet

For further guidance please read the Oxford/AstraZeneca vaccination and rare blood clotting information leaflet.

Capillary leak syndrome

Extremely rare reports of capillary leak syndrome have been reported after the Oxford/AstraZeneca vaccine in individuals with a prior history of this condition. You may be offered an alternative coronavirus vaccine.

Reporting side effects

As with all vaccines, you can report suspected side effects through the Yellow Card website.

Can I catch coronavirus from the vaccine?

You cannot catch coronavirus from the vaccine. But you can catch it before you get your vaccine and not know you’ve got it until after your vaccine appointment.

Read the coronavirus vaccine leaflets, including in other languages

Last updated:
11 August 2022