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Should I be concerned with side effects from the COVID-19 vaccine?

Posted May 06, 2021 by Charles A. Zonfa, MD, FACOG | Chief Medical Office

People around the country are lining up to get one of three available COVID-19 vaccines — Moderna, Pfizer and Johnson & Johnson — that have been authorized by the U.S. Food and Drug Administration (FDA) for use to combat the virus.

The COVID-19 vaccine is a crucial step to help guard against severe illness, hospitalization and even death from the virus. It also is an important tool to help stop this ongoing pandemic.

But before you roll up your sleeve, know you may experience mild side effects from these vaccines. The side effects are similar for all three vaccines and most commonly include:

  • Injection site pain, redness and swelling
  • Fatigue
  • Headache
  • Muscle and joint pain
  • Fever and chills
  • Nausea
  • Swollen lymph nodes

    All of these mild to moderate side effects are not dangerous. They are temporary and most resolve within a few days. More than anything, it’s a sign that the vaccine is working.

    Vaccines can cause side effects because they are signaling your immune system to respond to an unknown pathogen or foreign object in your body. So, when you feel these side effects, take comfort in knowing it’s a sign that your body is building protection against the virus.

    However, if don’t experience side effects, that does not mean you have any less protection. Everybody’s body is different.

    How to treat COVID-19 vaccine side effects

    The side effects from the COVID-19 vaccine could affect your ability to do daily activities, but most of them will go away on their own after a few days. That’s why the Centers for Disease Control and Prevention (CDC) recommends planning for rest and relaxation in the first few days following the vaccine.

    If you experience pain and discomfort at the injection site, taking over-the-counter pain relievers, such as ibuprofen, aspirin or acetaminophen, at the onset of symptoms can help. (The CDC recommends Tylenol for pregnant women.) You also can apply a cool, wet washcloth over the area. Using and exercising that arm also can help relieve symptoms.

    In addition, these same medications can help relieve fever and body aches, in addition to rest and drinking plenty of fluids.

    Note, however, the CDC advises against taking any of these pain relievers before you receive the vaccine because the impact on the immune response is not known.

    If you develop a rash, itchiness or redness at the injection site several days later, it could be a mild allergic reaction. You can treat the symptoms with an over-the-counter antihistamine, such as Benadryl, or a topical steroid cream, like hydrocortisone.

    Call your doctor if your symptoms persist or get worse after a few days. If you think you might be experiencing a severe allergic reaction after leaving the vaccination site, seek immediate medical care by calling 9-1-1.

    Though these side effects are inconvenient, take comfort in the long-term benefits of the COVID-19 vaccine. It offers you a high level of protection against long-term health complications and organ damage from COVID-19, as well as the ability to help stop the spread.

    Rare side effect from the Johnson & Johnson vaccine

    An increased risk of a rare condition called thrombosis with thrombocytopenia syndrome (TTS) has been discovered with the Johnson & Johnson vaccine. It involves blood clots with low platelets and has been found to occur in vaccinated women between 18 and 49 years old at a rate of about 7 per 1 million people. For women 50 years of age and older and men of all ages, this adverse event is even more rare.

    Despite this finding and a temporary pause in vaccine administration, the CDC and the FDA recommend use of the Johnson & Johnson COVID-19 vaccine. They reviewed the available data and believe the known and potential benefits outweigh its known risks.

    However, if you are a woman younger than age 50 be aware there are other COVID-19 vaccine options available for which this risk has not been found.

    For three weeks after receiving the vaccine, the CDC advises you to be on the lookout for possible symptoms of a blood clot with low platelets, including:

  • Severe or persistent headaches or blurred vision
  • Shortness of breath
  • Chest pain
  • Leg swelling
  • Persistent abdominal pain
  • Easy bruising or tiny blood spots under the skin beyond the injection site

    If you develop any of these symptoms, seek emergency medical care right away.

    Be sure to enroll in V-Safe Health Checker to report any side effects after receiving the COVID-19 vaccine so the CDC can continue to monitor the safety of the vaccines.


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