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

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

Can the vaccine cause irregular periods or unexpected bleeding?

Period problems are extremely common. They can be caused by a variety of factors including stress and other short-term illnesses. Some people may experience heavier than normal periods in the month or so after vaccination. While other changes to periods have been reported by some people after vaccination, there is no evidence that these were due to the vaccine.

Last updated:
13 January 2023