Most reports of adverse reactions following COVID-19 vaccination concern known and transient adverse reactions such as headache, fatigue, malaise, fever, nausea and pain in the body. These usually appear on the first or second day after vaccination and last around two to three days. These are known adverse reactions which are described in the product information.
After the administration of more than 3.5 million doses of COVID-19 vaccines in Norway, we have assessed 11,297 adverse reactions reports. Reports of serious events are assessed first. The figures therefore do not give a true picture of the distribution between serious and non-serious events.
Click here to go to an overview of reports of suspected adverse reactions (the adverse reactions report)
Reports of menstrual disorders
The Norwegian Medicines Agency has received a number of adverse reaction reports concerning menstrual disorders. As of today, we have assessed just over 50 reports of various types of menstrual disorders. The reports do not concern the same type of menstrual disorders, but various ailments such as severe menstruation and changes in menstrual patterns with delayed or premature menstruation. These reports are not classified as serious, but we will be monitoring them going forward.
Menstrual disorders are very common and many women have now been vaccinated. Many women will therefore experience disorders with a temporal link to their vaccination.
There is no evidence to suggest that this is linked to the vaccine, but we are monitoring the situation. Menstrual disorders are very common, and there may be many reasons why they occur. It is important that women see a doctor in the event of persistent or worrying symptoms, so that any other causes behind changes in menstrual pattern can be identified," says Steinar Madsen, Medical Director of the Norwegian Medicines Agency.
There is no evidence to indicate that any of the COVID-19 vaccines affect women's fertility.
Reports concerning heart problems
A number of cases of the heart disorders pericarditis (inflammation of the lining around the heart) and myocarditis (inflammation of the heart muscle) have been reported. In the USA, the Center for Disease Control and Prevention (CDC) is investigating whether there is a probable link between heart-related adverse reactions and the mRNA vaccines Comirnaty (BioNTech/Pfizer) and Spikevax (the Moderna COVID-19 vaccine), but its current view is that the benefits of vaccination outweigh the risks.
The European medicines authorities began their investigation in April after cases of myocarditis had been reported in Israel. They are now working to determine whether there is a link between the vaccines and reported cases of pericarditis and myocarditis within the EU/EEA.
The Norwegian Medicines Agency has reported Norway’s cases to the European Medicines Agency (EMA) as a possible adverse reaction signal and has provided information on the matter on an ongoing basis.
Reported cases in Norway
42 cases of acute pericarditis:
- 32 cases following vaccination with Comirnaty (BioNTech/Pfizer)
Comirnaty is the most widely used vaccine in Norway, with almost three million doses having been administered.
- Eight cases following vaccination with Spikevax (the Moderna COVID-19 vaccine)
- One case following vaccination with Vaxzevria (AstraZeneca)
- In one case, the patient had received Vaxzevria as the first dose and Comirnaty as the second.
Seven cases of myocarditis:
- Six cases following vaccination with Comirnaty (BioNTech/Pfizer)
- One case following vaccination with Spikevax (the Moderna COVID-19 vaccine).
- The vast majority of patients were recovering at the time the report was submitted.
Both pericarditis and myocarditis are rare conditions. They have a good prognosis, and most cases are mild and do not require any treatment. In some cases, the function of the heart may be severely impaired, necessitating hospitalisation of the patient. Anyone who experiences worrying breathlessness or chest pain should seek a doctor, regardless of whether or not they have been vaccinated.
All cases of pericarditis and myocarditis which arise following vaccination against COVID-19 should be reported.
How to report adverse reactions
It is particularly important to report reactions where any of the following are suspected:
- new adverse reactions not referred to in the patient information leaflet
- unexpected adverse reactions
- serious adverse reactions
vaccine failure (severe COVID-19 following full vaccination). If a person becomes seriously ill with COVID-19 one to two weeks following the completion of vaccination, this is considered to constitute a possible vaccine failure.
The general population can report adverse reactions via Helsenorge.no, but you should consult a doctor or other health professional in the case of suspected serious or unexpected adverse reactions following vaccination. You do not need to report a possible adverse reaction yourself if a health professional has already reported the reaction.
Health professionals are obliged to report suspected serious adverse reactions following vaccination via melde.no. It is not necessary for the causal relationship to be known; suspicion is sufficient to report an incident.