Side effects more common after 2nd Moderna shot, 1st AstraZeneca

General physical complaints, which are normal with coronavirus vaccinations, are experienced more often after the second vaccination with Moderna than after the first shot. With the AstraZeneca vaccine, this is the other way around, reported Side Effects Center Lareb after research. With Pfizer/BioNTech there is virtually no difference.

The complaints such as headache, muscle pain, fatigue, feeling unwell, nausea, chills and fever are known side effects after vaccinations. "At least of of these side effects is experienced more often after the second Moderna vaccination (79 percent) than after the first (56 percent)," Lareb said. With the AstraZeneca vaccine, this is 39 percent after the second shot and 86 percent after the first shot. With the Pfizer/BioNTech vaccine, complaints are experienced in about a quarter of the cases, both after the first injection and after the second.

Lareb conducted research on more than 18,000 people who had both injections. This concerns more than 10,200 participants with the Pfizer/BioNTech vaccine, more than 5,500 with the AstraZeneca vaccine and more than 2,400 with the Moderna vaccine.