After having a vaccination, some adolescents may feel a bit unwell for a few days and then get better.
Serious side effects are very rare. When they do occur, it is important for adolescents to get the support they need from a healthcare professional or at a hospital.
Some adolescents might feel a bit unwell for a day or two after they get their vaccinations. Common reactions are generally mild and go away on their own after a few days. These reactions can include local swelling, redness or pain at the injection site, mild fever, headache or tiredness.
Serious side effects are very rare, but they can happen, and some parents want to know more about them before they vaccinate their adolescent.
Anaphylaxis is a severe allergic reaction to one or more vaccine components. About 0.0001% (1 in 1,000,000) of people have this reaction following vaccination.1 Anaphylaxis usually happens within 15 minutes of receiving a vaccine, most likely before your adolescent leaves the school or clinic setting, and can be treated with an injection of adrenaline. People who have this reaction usually recover quickly and don’t experience any long-term effects.1
Less than 2% of adolescents can experience a large (extensive) amount of limb or arm swelling after receiving booster doses of the combination vaccine that protects against whooping cough (pertussis), diphtheria and tetanus. This reaction usually happens within 48 hours, lasts for 1–7 days and then resolves completely.2
Around 0.5–1 in 100,000 of tetanus toxoid-containing vaccine doses given in adults are linked to a swelling or inflammation of a nerve in the arm (brachial neuritis), which causes weakness or numbness.3,4 The seriousness and how long this reaction lasts varies on a case-by-case basis.
Guillain-Barré syndrome (GBS) is a rare disorder where a person’s immune system damages their peripheral nerve cells. It usually begins with tingling and weakness in the legs and can spread to the arms and face, leading to muscle weakness, loss of sensation and problems swallowing or breathing. While many people recover fully, others may continue to experience persistent symptoms.5,6 GBS occurs at a very low rate of up to 1 in 1,000,000 doses of influenza (flu) vaccine (0.0001%).7 People infected with the flu are more likely to get GBS than people who get the flu vaccine.8,9
One study from France showed the possibility of a very small increased risk (approximately 1 in 100,000 girls vaccinated) of a person developing GBS after receiving a human papillomavirus (HPV) vaccine.10 However, other large studies that collectively included more than 10 million people showed that GBS is very rare and the evidence for it being associated with HPV vaccination is weak.11,12,13,14
Very rarely (0.001–0.002% of doses, or 1–2 in every 100,000), people receiving a vaccine that protects against COVID-19 can experience a swelling or inflammation of the heart muscle (myocarditis) or the lining of the heart (pericarditis).15
Yes. When vaccination is recommended for your adolescent, the benefits of vaccination outweigh the risk of a vaccine side effect. While rare, some of these infectious diseases can have life-long effects on the adolescents who catch them. Some of these diseases can even be fatal.
Compared to catching a vaccine preventable disease, the side effects of vaccination are usually mild (like getting a sore arm or feeling tired) and go away quickly. Most of the common reactions will last between 12 and 24 hours and then get better.
Please note: In SKAI Adolescent, the phrase ‘your adolescent’ refers to all guardian relationships where health decisions for an adolescent fall under your responsibility.
Drafts of this page were reviewed by members of our Consumer Advisory Group.