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The FDA Just Warned About These 13 COVID Vaccine Side Effects

The FDA just announced them publicly for the first time.

With the arrival of the first coronavirus vaccine came the arrival of the first reported severe side effects—two medical workers in the U.K. had a bad allergic reaction, leading to the FDA today to warn Americans that if they have a history of severe allergic reactions, they should not take the vaccine, either. Other than that, "we have not seen any severe adverse events that we could relate to the vaccine thus far," says Dr. Anthony Fauci, the nation's leading infectious disease expert. "Safety is a very important issue," he said, adding that "when you look at the hundreds and hundreds of millions of people who've been vaccinated, the long-term adverse events have been less than minuscule in the big picture of the protection that you get from a vaccine." Nonetheless, they exist. The FDA just announced them publicly for the first time. Read on to see their warning, and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had Coronavirus


First of All, Remember the Big Benefit of the Vaccine

Female patient smiling behind the face mask and with her eyes, while getting flu shot

Says the FDA: "In an ongoing clinical trial, the Pfizer-BioNTech COVID-19 Vaccine has been shown to prevent COVID-19 following 2 doses given 3 weeks apart. The duration of protection against COVID-19 is currently unknown." The reported side effects have not been severe but you should know about them—keep reading.


You Might Feel Injection Site Pain 

Uncomfortable young woman scratching her arm while sitting on the sofa at home.

Dr. Fauci has described this as a "pain in the arm." For many, this will pale in comparison to the "whole lot of pain" Fauci has predicted from the coronavirus pandemic itself. If you've ever gotten a flu shot, it's apparently like that—some tenderness that fades. Although for some, it has been reported to be more painful. After getting her second dose, "my arm quickly became painful at the injection site, much more than the first time," wrote one nurse researcher, Kristen Choi, Ph.D., RN, who wanted to raise awareness about the "worst-case scenario" side effects of the two-part vaccine, in an essay in JAMA Internal Medicine.


Injection Site Swelling or Redness

Woman removing adhesive plaster from the wound after blood test injection

You might also expect "local swelling, irritation" in your arm, former FDA Chief Dr. Margaret Hamburg told CNBC's Squawk Box on Thursday.


You Might Get a Fever

woman is looking at the thermometer. She has fever

Fauci has said you might expect "a fever." This is likely to be mild, although it was not for Choi. "When I woke up again at 5:30 am, I felt hot. Burning. I took my temperature and looked at the reading: 104.9 °F (40.5 °C). This was the highest fever I can ever remember having, and it scared me. I took acetaminophen and drank a glass of water. When the research office opened at 9 am, I called to report my reaction to the injection. Thankfully, my fever had come down to 102.0 °F (38.9 °C) by then." 


You Might Feel Tired

Woman stressed out in an office

You might feel a "sense of fatigue," says Hamburg. This may mean the vaccine is doing its job. "The Covid-19 vaccines are 'more reactogenic than the flu vaccine,' said Arnold Monto, an epidemiologist at the University of Michigan who leads the panel of experts that will advise the FDA about authorizing Covid-19 vaccines," according to the Wall Street Journal—reactogenic meaning something causes an immunological reaction. "But reactogenicity is perfectly normal, he added, and people shouldn't be caught by surprise or dissuaded from getting the vaccines, which come in two shots spaced three or four weeks apart."


You Might Experience a Headache 

Man is having a headache.

Fauci has only frequently and publicly mentioned the fever and a pain in the arm as likely side effects. But there are others. Choi says "by the end of the day, I…had a splitting headache." Certainly some of the reported side effects include "some pain…sometimes headache," says Hamburg. 

RELATED: COVID Symptoms Usually Appear in This Order, Study Finds


You Might Have Muscle Pain

female touching neck and shoulder in pain.

Likely to be localized in the arm, but potentially appearing elsewhere, some of these pains may be signs that your immune system is making antibodies in response to the viruses in the vaccine.


You Might Get the Chills 


Choi reported feeling "chilled." "In a percentage of patients, they had chills and low-grade fever," said Hamburg.


You Might Experience Joint Pain 

woman holding her hand

You "could have fever — including rarely high fever — fatigue, headaches, chills, muscle aches, joint pain, enough so that one could miss a day of work," Dr. Paul Offit, a pediatrician at the Children's Hospital of Philadelphia and a member of the FDA's advisory committee evaluating the vaccines, tells NPR.


You Might Feel Nauseous

Woman Suffering From Nausea

Choi felt "nauseous." This can be a common side effect of the flu shot also, but is commonly characterized as mild.


You Might Feel "Unwell"

woman with hands holding pressing her crotch lower abdomen

Well, if you felt nauseous, chilled and had a fever or muscle aches, you might describe that as "unwell." An overall malaise might just be your immune system working.

RELATED: 7 Side Effects of Wearing a Face Mask


You Might Have Swollen Lymph Nodes (lymphadenopathy)

woman touching neck with her hands.

Your lymph nodes filter substances throughout your body, and are in your neck, armpits, goin and elsewhere. "A locally enlarged lymph node usually refers to immunological activity after vaccination," reports the Finnish Institute for Health and Welfare. "In particular, vaccines containing live pathogens effectively form antibodies in the lymph nodes closest to the vaccination site. An enlarged lymph node is usually detected within one week of vaccination….While enlarged lymph nodes do not require treatment, they must be monitored."


There is a Remote Chance of a Severe Allergic Reaction

Asian woman having difficulty breathing in bedroom at night

"There is a remote chance that the Pfizer-BioNTech COVID-19 Vaccine could cause a severe allergic reaction. A severe allergic reaction would usually occur within a few minutes to one hour after getting a dose of the Pfizer-BioNTech COVID-19 Vaccine. Signs of a severe allergic reaction can include: 

  • Difficulty breathing 
  • Swelling of your face and throat
  • A fast heartbeat 
  • A bad rash all over your body 
  • Dizziness and weakness."


Other Possible Side Effects

Chemist Adjusts Samples in a Petri Dish with Pincers and then Examines Them Under Microscope

"These may not be all the possible side effects of the Pfizer-BioNTech COVID-19 Vaccine. Serious and unexpected side effects may occur. Pfizer-BioNTech COVID-19 Vaccine is still being studied in clinical trials," reports the FDA. "If you experience a severe allergic reaction, call 9-1-1, or go to the nearest hospital. Call the vaccination provider or your healthcare provider if you have any side effects that bother you or do not go away."


How to Stay Healthy During the Pandemic

Female Wearing Face Mask and Social Distancing

As for yourself, discuss these issues with a medical professional if you have cause for concern, and until we're all vaccinated: Wear a face mask, social distance, avoid large crowds, don't go indoors with people you're not sheltering with (especially in bars), practice good hand hygiene and to protect your life and the lives of others, and 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
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