Side effects of the coronavirus vaccines

Like all medicines, the coronavirus (COVID-19) vaccines can cause side effects. It’s normal to experience side effects after a 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 coronavirus 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

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.

Even if you’ve had side effects after a previous dose, NHS Scotland recommends you get all the doses you’re eligible for, unless your side effect was severe. You should discuss any previous side effects with your health care professional at your appointment.

Uncommon side effects

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.

Very rare side effects

Heart inflammation

Cases of inflammation of the heart (called myocarditis or pericarditis) have been reported very rarely after the coronavirus vaccine.

These rare cases have been seen mostly in younger men and within several days of vaccination. Most of the people affected have felt better and recovered quickly following rest and simple treatments.

You should seek medical advice urgently if, after vaccination, you experience:

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

Reporting side effects

Millions of people have had a coronavirus vaccine and the safety of the vaccines continues to be monitored. As with all vaccines, you can report suspected side effects through the Yellow Card website.

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.

Waiting time after your coronavirus vaccination

Because of a small risk of fainting, you should not drive for at least 15 minutes after your vaccination.

If you have a history of allergies, or if you had a reaction immediately after a previous dose, you may also be advised to stay for 15 minutes after the vaccine.

Last updated:
03 July 2023