The best prevention against COVID is to stay up-to-date on COVID vaccines, which include booster shots. It's safe to get COVID shots, but you can experience side effects afterward.
The temporary monovalent and bivalent booster side effects of vaccination—including chills, fever, headache, and body aches—are an immune response rather than an illness. The side effects generally only last a few days. Read on to learn more about what to expect from COVID-19 booster shots.
There are three different boosters available:
- Pfizer-BioNTech: A bivalent mRNA vaccine with two different components of SARS-CoV-2
- Moderna: Another bivalent mRNA vaccine
- Novavax: A monovalent protein subunit vaccine based on the original SARS-CoV-2 variant
About the Johnson & Johnson Vaccine
In the U.S., the Johnson & Johnson vaccine is no longer available. Individuals 18 and older who received a Johnson & Johnson vaccine should receive either a bivalent Moderna or Pfizer-BioNTech dose. They should be given this dose at least two months after the completed Johnson & Johnson primary series or the last monovalent booster dose.
Who Is Eligible for Booster Shots?
Eligibility for booster shots is as follows:
- Moderna: Moderna's bivalent booster is approved for people ages 6 and older who do not have a health condition preventing them from safely getting vaccinated, such as a previous allergic reaction, which is very rare.
- Pfizer: Pfizer's bivalent booster is approved for those ages 5 and older.
- Novavax: Novavax's monovalent booster administration is available under limited circ*mstances. Individuals ages 18 and older may get a Novavax booster if they completed FDA-approved or authorized vaccines, did not receive previous booster shots, and cannot or will not receive an mRNA vaccine and booster dose.
Common Booster Side Effects
Side effects from COVID-19 booster shots are similar to those from primary series vaccinations. Additionally, side effects are generally temporary. They only last for a few days. Here are the side effects you should look out for.
Side Effects of Moderna Booster
Common Moderna booster side effects have included:
- Chills
- Fatigue
- Headache
- Injection-site redness and swelling
- Muscle or joint pain
- Pain
Side Effects of Pfizer-BioNTech Booster
The Pfizer-BioNTech booster shares many side effects with the Moderna booster. Researchers also found that Pfizer-BioNTech booster side effects, like fatigue, fever, and bone pain, were similar to those after the second dose.
Side Effects of Novavax Booster
The side effects of this booster shot are the same as those for the Moderna booster, with the addition of injection-site tenderness. Also, adults reported having side effects more frequently following the Novavax booster compared to the second dose of the primary series.
Of more than 192 million people in the U.S. who were vaccinated against COVID with an mRNA vaccine, 1,626 developed an inflammatory heart condition called myocarditis within seven days of getting their shot. Most cases were in adolescents and men in their early 20s.
Other reported rare side effects from booster shots are:
- Bell's palsy
- Concentration difficulties
- Constipation
- Dizziness or vertigo
- Extra hair loss
- Painful and heavy menstruation
- Sore throat
Precautions
There are some precautions to consider when getting COVID booster vaccines. Healthcare providers may need to administer other COVID vaccine options if a person has a history of a non-severe allergy or non-severe, immediate reaction to a COVID vaccine ingredient.
Another precaution is related to any current illnesses. People with moderate or severe acute illnesses will have to wait to get vaccinated until their illness has improved.
People who have had heart muscle or heart tissue inflammation within three weeks following any of the COVID shots may not be able to get another dose. Also, individuals who had a rare condition called multisystem inflammatory syndrome (MIS) in the past three months should wait to get a booster. They should also talk to a healthcare provider about the risks.
While it's normal to have booster side effects, talk to a healthcare provider if you have concerns about your side effects or if the effects last longer than a few days. Some symptoms also require medical attention. Seek immediate medical care if you have signs of severe reactions or allergic reactions like:
- Abdominal pain
- Chest discomfort or tightness
- Diarrhea
- Difficulty breathing
- Dizziness and weakness
- Heart palpitations
- Hives
- Low blood pressure
- Nausea or vomiting
- Slurred speech
- Swelling of your face and throat
Tips for Reducing Booster Side Effects
Ways to reduce side effects from a COVID-19 booster shot include:
- Dressing comfortably if you experience a fever
- Drinking enough fluids
- Keeping your arm moving throughout the day
- Resting if possible
- Using a clean, cool cloth for swelling or discomfort around the injection site
COVID booster shots can cause side effects just like the primary series doses of COVID-19 vaccines. These symptoms may include headaches, muscle pain, and swelling at the injection site.
There are also rare side effects, like sore throat and menstruation changes, and serious side effects, like severe allergic reactions, that warrant immediate medical attention. Fortunately, in some cases, you can reduce side effects by, for example, getting rest and staying hydrated.
