Updated Janssen (J&J) COVID-19 Vaccine Frequently Asked Questions

We’re sharing the following information from the FDA Safety Information and Adverse Event Reporting Program. Updated: April 14, 2021

Why are the FDA and CDC recommending a pause in the use of the Janssen COVID-19 Vaccine? 

The FDA and CDC are reviewing data involving six cases reported to the Vaccine Adverse Event Reporting System (VAERS) of a low level of platelets in the blood in combination with a rare and severe type of blood clot called cerebral venous sinus thrombosis (CVST) in individuals who had received the Janssen COVID-19 Vaccine.  One individual died. All cases occurred in females ranging in age from 18 through 48 years. In some of the reported cases of CVST, blood clots also involved large veins in the abdomen.

Out of an abundance of caution, the FDA and CDC are recommending a pause in the use of the Janssen COVID-19 Vaccine while the FDA and CDC, including through its Advisory Committee on Immunization Practices investigate these reports of serious adverse events. This is important, in part, to help ensure that health care providers are aware of the potential for these adverse events and can plan for proper recognition and management due to the unique treatment required for CVST with low levels of platelets.

The safety monitoring program that is in place to monitor COVID-19 vaccines is working, as we were able to detect the reports of these very rare, serious adverse events early and take action to assess them.  The FDA and CDC will continue to fully investigate all reports to determine if a causal relationship exists.

If I received the Janssen COVID-19 Vaccine, am I at risk for these adverse events? 

If you received the vaccine a month or more ago, the risk of these events appears to be extremely low.  In all six cases, the symptoms occurred 6 to 13 days after vaccination.

You should contact your health care provider immediately if you are experiencing any of the following symptoms:  

  • shortness of breath
  • chest pain
  • leg swelling
  • persistent abdominal pain
  • neurological symptoms (including severe or persistent headaches or blurred vision)
  • a diffuse rash on the skin consisting of pinpoint like spots (petechiae).

These symptoms are distinct from the commonly reported side effects that people may experience in the first few days following vaccination, which can include headache, fatigue, muscle aches and nausea.  Most of these side effects are mild to moderate in severity and last 1-2 days.

What should health care providers look for in evaluating Janssen COVID-19 Vaccine recipients for these rare events? 

Healthcare providers should be alert to the signs and symptoms of thromboembolism and/or thrombocytopenia in individuals vaccinated with Janssen COVID-19 Vaccine. In the management of cases of thromboembolism with thrombocytopenia following Janssen COVID-19 Vaccine, heparin and its derivatives should be avoided, and health care providers should consider consulting a hematologist.  

Additional information for clinicians is available in CDC’s Health Alert Network notice, “Cases of Cerebral Venous Sinus Thrombosis with Thrombocytopenia after Receipt of the Johnson & Johnson COVID-19 Vaccine.”