57 Percent of Pfizer Recipients Have This Side Effect, New Study Finds

Kali Coleman
·3 min read

No matter which COVID vaccine you receive, there's a decent chance you'll experience some side effects the next day. From reactions in the arm where you got the shot to systemic reactions happening throughout your body, you can't be certain which side effects will affect you in particular. However, new research has shown some commonalities when it comes to the different vaccinations. One recent study concluded that more than half of Pfizer recipients have reported one side effect in particular. Read on to find out which reaction you're more likely to get than not with Pfizer, and for more on this vaccine, Pfizer's Vaccine Protects You for at Least This Long, Study Finds.

More than half of people who got the Pfizer vaccine experienced arm tenderness.

A new study published April 27 in the Lancet Infectious Diseases journal reported on the real-world safety and effectiveness of the Pfizer vaccine for recipients between December and March in the U.K. Out of 282,103 people who received the first dose of the Pfizer vaccine, 57.2 percent reported experiencing arm tenderness as a side effect. For the second dose, the percentage was more than half as well: According to the study, 50.9 percent of Pfizer recipients had arm tenderness after the second shot. And for more on vaccine reactions, This Vaccine Side Effect Could Mean You Already Had COVID, New Study Says.

Arm tenderness was the most common local side effect after either dose of the Pfizer vaccine.

For either dose of the Pfizer vaccine, arm tenderness was the most commonly reported local side effect. According to the study, 71.9 percent of those who received the first dose of Pfizer experienced local side effects, while 68.5 percent of those who received the second dose did. Arm pain was the most commonly reported local side effect after tenderness, with 29.2 percent experiencing arm pain after the first dose and 34.3 percent experiencing it after the second. Participants also reported experiencing swelling, itch, swollen armpit glands, redness, warmth, and bruising as local reactions to the Pfizer vaccine. And for more up-to-date information, sign up for our daily newsletter.

It was also the most commonly reported reaction for Pfizer recipients in general.

Arm tenderness and arm pain were the two most common side effects reported for Pfizer recipients in general. However, the third most common was a systemic side effect: fatigue. According to the study, 8.4 percent of recipients experienced fatigue after the first dose of Pfizer, and 14.4 percent had this side effect after the second. Other systemic side effects reported from the Pfizer vaccine included headache, chills and shiver, diarrhea, fever, joint pain, muscle pain, and nausea. And for more on the future of vaccination, Pfizer's CEO Just Said How Often You'll Need a COVID Vaccine.

Your arm tenderness should only last a few days.

According to the study, tenderness around the injection side occurred "most often on the day after injection" and lasted around one to two days on average. However, a small group did report experiencing this reaction for up to seven days after vaccination. The Centers for Disease Control and Prevention (CDC) recommends that you apply a clean, cool, wet washcloth over the injection site and use or exercise your arm to reduce any of the discomfort or tenderness where you got the shot. If you notice that the tenderness where you got the shot gets worse in any way after 24 hours, the CDC says you should contact your doctor or healthcare provider. And for more CDC guidance, The CDC Says You Should Immediately Do This Once You've Been Vaccinated.