What to Expect After Your COVID-19 Vaccine

Getting vaccinated is one way to help protect yourself from getting seriously ill with COVID-19. After your vaccine shots, you may experience some side effects. The most common ones are sore arm, muscle aches, headache, feeling tired, chills or fever.

Even if the side effects mentioned above are strong enough to affect your daily activities, they should go away in a few days and are not a sign you have COVID-19. The available vaccines don’t contain live coronavirus and can’t make you sick with COVID-19. The vaccine doesn’t work immediately. If you develop a sore throat, stuffy nose, altered taste or smell, cough, breathing problems, diarrhea or vomiting, these might mean that you have developed a COVID-19 infection before the vaccine started working.

If you think you’re having a severe allergic reaction, call 911 immediately.

When to Call Your Doctor

Call your primary care provider if your symptoms continue to worsen, you’re experiencing new symptoms not listed above, or the area where you got the shot gets increasingly red and tender after 24 hours.

According to the CDC, if you’ve received the Janssen/J&J vaccine and develop a severe headache, abdominal pain, leg pain or shortness of breath within three weeks of your vaccination, seek care right away. If you experience sudden onset of severe symptoms, call 911 or go to the nearest emergency room.

Building Immunity

Side effects are a sign your body is building immunity. For the Pfizer and Moderna mRNA vaccines to be most effective, two shots are required. Unless a provider tells you not to, you should get the second shot of mRNA vaccine, even if you have some side effects after the first one. For the Janssen COVID-19 Vaccine (Johnson & Johnson) viral vector vaccine, one shot is required.

Remember that it takes time for your body to build protection after vaccination. You’ll have maximum protection from COVID-19 14 days after either your second shot of an mRNA vaccine or after administration of the single-dose Janssen/J&J vaccine.

Helpful Tips

You can alleviate most side effects through simple measures at home. Acetaminophen can help reduce symptoms like fever and aches. For soreness in your arm, apply a cool, wet washcloth where you got the shot. Using and exercising your arm can also help.

Protecting Yourself and Others

Until we know for sure, we need to assume that those who are vaccinated may still be able to spread COVID-19 to unvaccinated persons, even if they don’t get sick themselves. When in public, continue to cover your nose and mouth with a mask, avoid crowds, wash your hands often and stay at least six feet away from other people. When you’ve been fully vaccinated, consider these guidelines from the CDC. We’re also awaiting more information about the long-term protection of the vaccines.