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What you need to know

  • The FDA says blood clot cases from the Johnson & Johnson COVID-19 vaccine are serious but rare. The vast majority of J&J recipients do not need to worry.
  • People who received the J&J vaccine should get an mRNA shot for their booster.
  • The decision to restrict use of the J&J vaccine demonstrates that our vaccine monitoring systems are working.

The FDA announced last week that it is restricting the use of the Johnson & Johnson COVID-19 vaccine due to the ongoing risk of serious but rare blood clots. The agency now says that the J&J shot should only be given to adults who cannot receive a different vaccine or who specifically request the J&J vaccine.

Here’s what you need to know about this change in guidance and which COVID-19 vaccines and boosters you should get going forward.

Why did the FDA limit the use of the Johnson & Johnson COVID-19 vaccine?

The agency restricted the J&J vaccine in response to the risk of developing blood clots, an issue first identified in spring 2021. As of mid-March, scientists have identified 60 blood clot cases from the vaccine. These cases resulted in nine deaths. This amounts to just one blood clot case per 3.23 million J&J shots administered. But the risk is much higher among women ages 30 to 49, at one case per 100,000 vaccine doses. This decision demonstrates that the FDA is committed to transparency and safety, and that our vaccine monitoring systems are working.

Why didn’t this limitation come sooner if blood clots have been an issue since last spring?

The FDA did not limit the vaccine earlier because the agency determined that the benefits of continuing to give the J&J vaccine outweighed the risks. (The CDC did issue a recommendation in December that prioritized Pfizer and Moderna’s shots over J&J’s because of safety issues.) 

The risk of blood clots is extremely rare. Even now, the FDA makes clear that receiving a J&J shot is still safer than remaining unvaccinated. But since mRNA vaccines are no longer in short supply, the agency has decided to prioritize COVID-19 vaccines developed by Pfizer and Moderna. These mRNA vaccines are just as effective and do not come with the risks associated with the J&J shot.

If I received a J&J vaccine, do I need to worry?

The symptoms related to blood clots tend to arise one to two weeks after vaccination, so if you received the J&J vaccine months ago, you do not need to worry. 

If you received a J&J shot recently and are concerned by the latest news, know that the risk of developing blood clots is still very unlikely. If you do develop concerning symptoms, seek medical help right away. Blood clot-related symptoms include:

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

What should J&J vaccine recipients do going forward?

Vaccines and boosters remain crucial to staying protected against COVID-19. If you received the J&J vaccine, the next step is to get your mRNA booster shot.

  • If you received the J&J vaccine for your primary series, you can get an mRNA booster two months later. 
  • If you received the J&J vaccine for both your primary series and booster shot, you can get an mRNA shot as a second booster four months after their first booster.