Second dose of coronavirus vaccine could cause worse side effects

COLUMBIA, Mo. (KMIZ)

As coronavirus vaccines continue to be rolled out around the world and here in Missouri, people are noticing worse side effects after receiving their second dose.

Margaret Day, a University of Missouri Health Care family doctor, said it is normal for people to feel stronger reactions after receiving the second dose.

"The second dose has stronger side effects because your body has now been exposed to that vaccine once and your immune system has boosted somewhat," she said.

When your immune system sees the second dose of the vaccine, Day said it will respond more forcefully.

"That's really your amazing body's design and really expected reaction after receiving the vaccine," she said.

Alexandra James, a pediatrician at MU Health, got her second dose of the vaccine in January and felt stronger side effects the second time around.

"Definitely the couple days after I was more fatigued I had some arm soreness and for about 24 hours later I did have general muscle aches," she said.

Another health care worker at Boone Hospital, Amy Bierk felt worse pain but not any new symptoms.

"The only symptom that I had was a sore arm, but it was more sore after the second dose," she said.

The only coronavirus vaccine shots approved for use in the U.S. right now are versions from Pfizer and Moderna, each of which requires two shots.

The U.S Food and Drug Administration reported the most common side effects are pain in the injection site, fatigue, muscle pain, chills, headache, joint pain and fever.

The FDA also reported more people are experiencing those side effects after the second dose, and vaccine providers and recipients should expect it.

According to the state's COVID-19 dashboard 427,152 Missourians have received the first dose of the coronavirus vaccine, and 125,943 have already received the second dose.

The Centers for Disease Control and Prevention said anyone who had a severe allergic reaction after the first dose of mRNA vaccines such as the coronavirus shots should not get a second dose.