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Pfizer-BioNTech COVID-19 Vaccine

Generic name: COVID-19 (coronavirus 2019) vaccine, Pfizer (KOE vid-19 koe ROE na vye rus VAX een)
Brand name: Pfizer-BioNTech COVID-19 Vaccine PF, Comirnaty
Dosage forms: intramuscular suspension (30 mcg/0.3 mL)
Drug class: Viral vaccines

Medically reviewed by Philip Thornton, DipPharm. Last updated on Jan 7, 2022.

What is the Pfizer-BioNTech COVID-19 Vaccine?

The Pfizer-BioNTech COVID-19 Vaccine may help your body develop immunity to SARS-CoV-2. The Pfizer COVID-19 Vaccine is used to help prevent severe disease and death from COVID-19 caused by SARS-CoV-2.

The US Food and Drug Administration (FDA) has fully approved the Comirnaty brand of Pfizer vaccine for use in people who are at least 16 years old.

The FDA has authorized emergency use of the Pfizer vaccine in people who are aged 5 years and older.

Pfizer-BioNTech COVID-19 Vaccine does not contain coronavirus and cannot give you COVID-19. This vaccine will not treat an active COVID-19 infection.

COVID-19 is a serious disease caused by a coronavirus called SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2). COVID-19 is spread from person to person through the air.

COVID-19 can affect your lungs or other organs. Symptoms may be mild or serious and include fever, chills, cough, sore throat, shortness of breath, tiredness, body aches, headache, loss of taste or smell, runny or stuffy nose, nausea, vomiting, or diarrhea.

Like any vaccine, the Pfizer COVID-19 vaccine may not provide protection in every person.


Becoming infected with COVID-19 is much more dangerous to your health than receiving Pfizer-BioNTech COVID-19 Vaccine.

If you have a certain type of reaction after the first dose of Pfizer-BioNTech COVID-19 Vaccine, your healthcare provider will determine if you can safely receive the second dose.

Before taking this medicine

You should not receive Pfizer-BioNTech COVID-19 Vaccine if you've ever had a severe allergic reaction to a Pfizer COVID-19 vaccine. Your healthcare provider will determine whether any reaction you have would prevent you from safely getting the second dose.

If you are infected with COVID-19, are waiting for testing results, or are exposed to someone infected with COVID-19: You may not be able to receive Pfizer-BioNTech COVID-19 Vaccine until you have no symptoms and/or your required quarantine period has ended. Receiving Pfizer-BioNTech COVID-19 Vaccine will not make you less contagious to other people if you are infected with COVID-19 but you have no symptoms.

If you had COVID-19 and were treated with monoclonal antibodies or convalescent plasma: You should wait 90 days before getting a COVID-19 vaccine. Ask your doctor if you are unsure about any COVID-19 treatments you received.

To make sure Pfizer-BioNTech COVID-19 Vaccine is safe for you, tell your doctor if:

  • you have a fever;

  • you have any allergies;

  • you have had inflammation in or around your heart (myocarditis or pericarditis);

  • you have bleeding problems, or if you use a blood thinner (warfarin, Coumadin, Jantoven);

  • you have a weak immune system caused by disease or by using certain medicine;

  • you are pregnant or breastfeeding;

  • you've received any other COVID-19 vaccine; or

  • you have fainted after receiving an injection.

COVID-19 is more likely to cause serious illness or death in a pregnant woman. Not all risks are known yet, but Pfizer-BioNTech COVID-19 Vaccine is likely to be less harmful than becoming infected with COVID-19 during pregnancy.

If you are pregnant, your name may be listed on a pregnancy registry to track the effects of COVID-19 vaccine on the baby.

How is Pfizer-BioNTech COVID-19 Vaccine given?

The Pfizer COVID-19 vaccine is given as an injection (shot) into a muscle, in a series of 2 shots given 3 weeks apart.

The Comirnaty brand of Pfizer COVID-19 vaccine is fully approved for people at least 16 years old.

The Pfizer BioNTech vaccine is authorized for emergency use in people who are aged 5 years and older.

The Pfizer vaccine is also authorized under the FDA's EUA procedure in a series of 3 shots for people 5 years and older who have received an organ transplant or have certain types of immunosuppression. The first 2 shots are given 3 weeks apart and the third shot is given at least 28 days after the second shot.

A single booster dose of Pfizer vaccine given at least 5 months after the primary series is also authorized for emergency use in people who are 12 years and older.

The booster dose is given at least 5 months after you received all required doses of the Pfizer COVID-19 vaccine. If you are 18 years and older, you can receive any COVID-19 vaccine for your booster dose (Pfizer, Moderna, or Janssen). If you are 12 years and older, you can receive Pfizer BioNTech vaccine for your COVID-19 vaccine booster dose.

Your doctor or vaccination provider will determine whether you need a booster dose.

You will receive a reminder card showing the date and type of each injection. Take this card with you each time you receive a COVID-19 vaccine.

You will be "fully vaccinated" if it has been at least 2 weeks since you received your last dose of Pfizer-BioNTech COVID-19 Vaccine. You may become infected with COVID-19 if the vaccine has not had enough time to provide protection.

Even after you are fully vaccinated, keep using infection control methods when you are in public or around others who may not have been vaccinated. This includes social distancing, hand-washing, using protective face covering, disinfecting surfaces you touch a lot, and not sharing personal items with others.

Receiving a COVID-19 vaccine will not cause you to test positive on a coronavirus test. However, once your body develops immunity to COVID-19, you could test positive on an antibody test (a test to detect immunity in your body from previous exposure to coronavirus).

It is not known how long Pfizer-BioNTech COVID-19 Vaccine will protect you from infection with COVID-19. It also is not known how long immunity will last in a person who's been infected with and recovered from COVID-19.

Pfizer-BioNTech COVID-19 Vaccine dosing information

Usual Adult Dose for COVID-19:

30 mcg IM for 2 doses, administered 21 days apart.

Usual Pediatric Dose for COVID-19:

5 to 11 years: 10 mcg IM for 2 doses, administered 21 days apart

12 to 15 years: 30 mcg IM for 2 doses, administered 21 days apart

16 years and older: 30 mcg IM for 2 doses, administered 21 days apart.

A third dose of Pfizer vaccine, administered at least 28 days following the first two doses of this vaccine, is authorized for individuals at least 5 years of age who have undergone solid organ transplantation, or who are diagnosed with conditions that are considered to have an equivalent level of immunocompromise.

A single booster dose may be given at least 5 months after the primary series to people who are 12 years and older.

No data are available regarding interchangeability of COVID-19 vaccine products; the same vaccine product should be used for both doses, however if two doses of different mRNA COVID-19 vaccines are inadvertently administered, no additional doses of either product are recommended at this time. Recommendations maybe updated as more information or vaccine types become available.

What happens if I miss a dose?

Be sure to receive all recommended doses of COVID-19 vaccine or you may not be fully protected. Contact your vaccination provider or health department if you miss your second dose.

What happens if I overdose?

An overdose of Pfizer-BioNTech COVID-19 Vaccine is unlikely to occur.

What should I avoid after receiving Pfizer-BioNTech COVID-19 Vaccine?

Avoid receiving other vaccines without first seeking medical advice.

Pfizer-BioNTech COVID-19 Vaccine side effects

Get emergency medical help if you have signs of an allergic reaction to Pfizer-BioNTech COVID-19 Vaccine: hives, rash; dizziness, weakness, fast heartbeats; difficult breathing; swelling of your face, lips, tongue, or throat.

Your vaccination provider may want to watch you for a short time after your shot, to make sure you don't have an allergic reaction. You will be treated quickly if you have a reaction right after you receive the vaccine.

You should not receive this vaccine again if the first shot caused a severe allergic reaction. Your doctor or vaccination provider will determine if you can safely receive another COVID-19 vaccine.

Not all possible side effects are known. Becoming infected with COVID-19 is much more dangerous to your health than receiving this vaccine.

Some people receiving Pfizer-BioNTech COVID-19 Vaccine had inflammation of the heart muscle or the lining around the heart within a few days after receiving this vaccine, but the risk of this side effect is very low. Seek medical attention right away if you have:

  • chest pain;

  • shortness of breath; or

  • fast or pounding heartbeats or fluttering in your chest.

Not all possible side effects are known.

Common Pfizer-BioNTech COVID-19 Vaccine side effects may include:

  • fever, chills, swollen glands, not feeling well;

  • pain, redness, or swelling where the shot was given;

  • feeling tired; or

  • headache, muscle pain, joint pain.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report vaccine side effects to the US Department of Health and Human Services at 1-800-822-7967.

You may also use a smartphone-based program called V-safe to communicate with the Centers for Disease Control and Prevention (CDC) about any health problems you have after receiving a COVID-19 vaccine.

What other drugs will affect Pfizer-BioNTech COVID-19 Vaccine?

Before receiving Pfizer-BioNTech COVID-19 Vaccine, tell your vaccination provider about all other vaccines you have received and all medicines you use. This includes prescription and over-the-counter medicines, vitamins, and herbal products.

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Further information

  • Your vaccination provider, pharmacist, or doctor can provide more information about Pfizer-BioNTech COVID-19 Vaccine. Additional information is available from your local health department or the Centers for Disease Control and Prevention.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use Pfizer-BioNTech COVID-19 Vaccine only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.