Fever, aching limbs, the so-called covid arm - a vaccination against the coronavirus can bring unpleasant side effects, regardless of which vaccine was inoculated. It is therefore natural to take painkillers such as ibuprofen or paracetamol to combat or even prevent such complaints. The Robert Koch Institute (RKI) even suggested in an information sheet on vaccination (11.01.2021) to take paracetamol for fever and pain after vaccination. But as it now appears, taking painkillers too early could impair vaccination protection.

Researchers at the University of British Columbia in Vancouver are currently investigating whether painkillers should be taken at all for a vaccine reaction to the Corona vaccine. Based on side effect data and "given the availability of over-the-counter antipyretics, potentially millions around the world are expected to use them to moderate acute systemic side effects associated with COVID-19 vaccination," the researchers write in a preprint to appear soon in the journal Chest.

Painkiller after Corona vaccination may lower effect
Why this might be problematic? Some studies - not all, the researchers point out - indicate that painkillers, when taken before or immediately after a vaccination, could lower vaccine protection. That's because they can suppress the natural vaccination response, which can manifest as fever, for example. The health portal "aponet.de" writes, "through a suppressed immune reaction, the formation of antibodies and thus the effect of the vaccination could theoretically be diminished." Incidentally, this applies not only to Corona vaccinations, but also to vaccinations against other diseases.

A study in the journal The Lancet demonstrated that taking acetaminophen to prevent side effects when vaccinating a cohort of children reduced antibody titers. Also, a 2014 paper showed for adults that administration of acetaminophen at least six hours after vaccination had no effect on the immune response, while immediate administration after vaccination attenuated it. However, specifically for the Corona vaccines, such as those from Biontech, Moderna and AstraZeneca, the impact that painkillers taken as a preventive measure may have on immunization has not yet been studied.

Astrazeneca and Co: No data on painkillers from vaccine makers
A study on the recently suspended AstraZeneca vaccine does mention that prophylactic administration of paracetamol does not affect immunogenicity - the ability of the vaccine to trigger an immune response in the body. However, no data on this have been published, the researchers in Canada note. Moreover, it is not certain whether the results can be applied to mRNA-type vaccines, such as Biontech and Moderna. In the case of AstraZeneca, the vaccine is a vector vaccine. In the case of Moderna, no data on the use of antipyretics had been published; Biontech and Pfizer had only mentioned that the use of antipyretics increased with increasing dosage and number of doses. Nothing had been disclosed on immunogenicity.

Regardless of the Corona pandemic, the World Health Organization (WHO) and the U.S. Centers for Disease Control and Prevention recommend that pain relievers not be taken before or shortly after vaccination. Only in the days following vaccination could they be taken to combat side effects.

Photo by Christine Sandu