HuffPost UK reader Ed asked: “What should I do if I experience a negative side effect of the Covid-19 vaccine?”
For some, side effects are part and parcel of having the Covid-19 vaccine – but they’re not thought to be particularly serious.
The most common side effects of the vaccines are a sore arm (as the vaccine is administered into the upper arm), headache, feeling tired or achey, and feeling nauseous or being sick. These are considered mild issues and, according to the NHS, should not last longer than a week.
It’s understood that we get these reactions because our immune response is being triggered by the body to the vaccines.
What are the possible side effects?
Side effects appear to be less common in those aged over 55 than those aged 16 to 55. While they can crop up after the first dose, that shouldn’t put you off having the second dose as side effects are reported to be milder the second time around.
With the Pfizer vaccine, any side effects you do experience should be mild or moderate and go away within a few days. In a final safety analysis of the vaccine involving more than 21,000 participants, the most common side effects were injection site pain, fatigue, and headache.
Other side effects which are quite common, impacting around one in 10 people, include: muscle pain; chills; joint pain; fever; and nausea.
There have been cases where people have had more uncommon side effects, thought to affect up to one in 100 people, such as enlarged lymph nodes and generally feeling unwell. Rare side effects, which impact one in 1,000 people, include temporary one-sided facial drooping and in very rare instances, severe allergic reactions.
Those with a history of anaphylaxis to food, an identified drug or vaccine, or an insect sting can still receive the Covid-19 vaccine, as long as they are not known to be allergic to the vaccine ingredients, the Medicines and Healthcare products Regulatory Agency (MHRA) has said.
The Pfizer vaccine, for example, contains polyethylene glycol (PEG) – a known allergen commonly found in medicines, household products and cosmetics.
If you are allergic to PEG, you can have the AstraZeneca vaccine instead. If you don’t know whether you’re allergic to PEG, it’s worth bearing in mind that people with undiagnosed PEG allergy may have a history of unexplained anaphylaxis or anaphylaxis to multiple classes of drugs. Chat to your GP if you’re worried.
The British Society for Allergy and Clinical Immunology (BSACI) has said people who have a localised itchy skin reaction to the first dose of a Covid-19 vaccine should receive the second dose with prolonged observation afterwards (roughly 30 minutes) in a setting with full resuscitation facilities.
Severe allergic reactions are very rare and usually happen within minutes of having the vaccine. It’s important to remember that the staff giving the vaccine are also trained to deal with allergic reactions – so you’re in safe hands.
The AstraZeneca vaccine has similar common side effects to the Pfizer jab. These include: tenderness pain, warmth, redness, itching, swelling or bruising where the injection is given; generally feeling unwell; feeling tired; chills or feeling feverish; headache; feeling sick (nausea); joint pain or muscle ache.
Side effects impacting up to one in 10 people include: a lump at the injection site; fever; being sick; and flu-like symptoms (high temperature, sore throat, runny nose, cough and chills). While uncommon symptoms, affecting one in 100 people, include: dizziness; decreased appetite; abdominal pain; enlarged lymph nodes; excessive sweating; and itchy skin or a rash.
In clinical studies, most side effects from both jabs were mild to moderate in nature and resolved within a few days.
Reports suggest the vaccine is facing some resistance in Europe after side effects led hospital staff and other front-line workers to phone in sick. A spokesperson for AstraZeneca told Reuters: “Currently, the reactions reported are as we would expect based on the evidence gathered from our clinical trial programme.”
It’s thought people who’ve had Covid-19 before might be more likely to experience side effects from the vaccine. Research from New York found people with Covid-19 antibodies were more likely to report fatigue, headache, chills, fever and muscle or joint pain after receiving a single dose of an mRNA vaccine (which is what the Pfizer jab is), The Times reported.
You feel rough after your jab. Now what?
First of all, there’s no need to panic. Like the flu shot or any other vaccine for that matter, you might feel a bit rubbish in the next few days.
If you have mild side effects like aches, pains and fever the NHS suggests taking a painkiller such as paracetamol. It’s quite common to get a mild fever after the jab which resolves itself in roughly 48 hours – if you have a fever for longer than that, or any other symptoms of the virus, consider getting a Covid-19 test.
People who experience any side effects, whether mild or more severe, can report these on the Yellow Card website to help inform vaccine safety going forward. This includes side effects that might not be listed above.
Some side effects might impact your ability to drive and use machines – so if you do feel unwell after the jab, you’re urged not to use them until the symptoms pass.
The good news is that the expected benefits of both Covid-19 vaccines in preventing the virus and any serious complications far outweigh any known side effects.
Experts are still learning about Covid-19. The information in this story is what was known or available at the time of publication, but guidance could change as scientists discover more about the virus. To keep up to date with health advice and cases in your area, visit gov.uk/coronavirus and nhs.uk.