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Don't Worry if This Happens After Your Vaccine, Says CDC

These side effects are perfectly normal—in fact, it means the vaccine is working, says the CDC.
FACT CHECKED BY Emilia Paluszek

Now that there's a third vaccine available—and distribution is ramping up to the tune of more than 2 million shots per day—you'll be getting yours any month now. The CDC wants you not to worry about any side effects; not only is the vaccine safe, they say, but your body reacting is a good sign. "After getting vaccinated, you may have some side effects, which are normal signs that your body is building protection," says the CDC. Read on for the CDC's full list of side effects that they say not to worry about—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had Coronavirus


You May Experience Pain and Swelling in the Arm

A man experiencing discomfort in his upper arm

"The most common side effects are pain and swelling in the arm where you received the shot," says the CDC. Dr. Anthony Fauci, the chief medical advisor to the President and the director of the National Institute of Allergy and Infectious Diseases, said he felt a slight pain in his arm after getting the vaccine.  "After the first prime, my arm hurt a little bit," said Dr. Fauci. "If I pressed on it, I felt the little ache in the arm went to bed at night, and woke up the next morning. It lasted maybe into the next day, but by the night time of the second day, it was gone."


You May Develop a Fever and Chills

Woman having throat ache

"At about 2 a.m. on Thursday morning, I woke to find my husband shivering beside me. For hours, he had been tossing in bed, exhausted but unable to sleep, nursing chills, a fever, and an agonizingly sore left arm," Katherine J. Wu wrote in the Atlantic. "His teeth chattered. His forehead was freckled with sweat. And as I lay next to him, cinching blanket after blanket around his arms, I felt an immense sense of relief. All this misery was a sign that the immune cells in his body had been riled up by the second shot of a COVID-19 vaccine, and were well on their way to guarding him from future disease." Side effects are natural, she notes, and also added that not everyone will experience them.


You May Feel Tiredness

Woman sleeping on the couch in the living room.

It was "a little bit different with the boost," said Dr. Fauci, "with the boost, which was 28 days later for me, again, I had a little bit of an ache in the arm, but towards the evening, I started to feel a bit fatigued." Many people plan to take the day after their second shot off work, in case they feel too sluggish to go in.


You May Get a Headache

Woman having headache migraine. Stress and depression.

One Ohio young adult got a headache—as well as other side effects, like throwing up. "Your immune system is just getting revved up. You're sort of revved up by the first shot, and then that second booster just puts your immune system into overdrive, and so there's definitely a higher rate of side effects," Dr. Jeffrey Weinstein, the patient safety officer for Kettering Health Network, told WHIO-TV. "These side effects are pretty short lived. They typically last for a few hours," Dr. Weinstein said. "They're a lot less than actually having the symptoms of actually being sick with Covid."

RELATED: Dr. Fauci Just Said When We'd Get Back to Normal


What to Do if You Feel These Side Effects

Doctor and senior woman wearing facemasks

Don't worry too much if you experience these side effects. "These side effects may affect your ability to do daily activities, but they should go away in a few days," says the CDC. "In most cases, discomfort from pain or fever is a normal sign that your body is building protection. Contact your doctor or healthcare provider:

  • If the redness or tenderness where you got the shot gets worse after 24 hours
  • If your side effects are worrying you or do not seem to be going away after a few days."

And to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.

Alek Korab
Alek Korab is a Co-Founder and Managing Editor of the ETNT Health channel on Eat This, Not That! Read more about Alek