The FDA is working to address the coronavirus disease 2019 (COVID-19) outbreak and keep you and your family informed on the latest developments. Here are answers to some frequently asked questions from consumers about vaccines, side effects, and the Vaccine Adverse Event Reporting System.

Q: Why are the FDA and CDC recommending a pause in the use of the Johnson & Johnson (Janssen) COVID-19 vaccine?

A: The FDA and CDC are reviewing data involving 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. The FDA recommended the pause after becoming aware of six cases, of the nearly 7 million doses administered so far in the United States. One person died. All cases occurred in women ages 18 to 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 we 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 in place to monitor COVID-19 vaccines is working. We were able to detect the reports of these very rare, serious adverse events early and take action. The FDA and CDC will continue to fully investigate all reports to determine if a causal relationship exists. For more information, visit this CDC page.

Q: If I received the Johnson & Johnson (Janssen) COVID-19 vaccine, am I at risk for these adverse events?

A: 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 six to 13 days after vaccination.

Contact your health care provider immediately if you are experiencing any of these 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 after vaccination, which can include headache, fatigue, muscle aches and nausea. Most of these side effects are mild to moderate, and last one to two days.

Q: How do I report COVID-19 vaccine side effects?

A: If you experience a severe allergic reaction or any life-threatening symptoms – such as trouble breathing – call 911, or go to the nearest hospital.

Call the vaccination provider or your health care provider if you have any side effects that bother you or do not go away.

Report vaccine side effects to the FDA/CDC Vaccine Adverse Event Reporting System (VAERS) by calling 1-800-822-7967 or going online. Please include the name of the vaccine in the first line of box #18 of the report form.

You may also be given an option to enroll in v-safe. V-safe is a new voluntary smartphone-based tool that uses text messaging and web surveys to check in with vaccinated people to identify potential side effects after COVID-19 vaccination. V-safe asks questions that help CDC monitor the safety of COVID-19 vaccines. V-safe also provides second-dose reminders, if needed, and live telephone follow-up by CDC if participants report a significant health impact following COVID-19 vaccination. For more information on how to sign up, visit: www.cdc.gov/vsafe.

For the latest information about COVID-19, visit:

• FDA: Coronavirus Disease 2019 (COVID-19)
• FDA: COVID-19 Vaccines
• CDC: Coronavirus (COVID-19)
• U.S. Department of Health and Human Services

View Webpage

The FDA is working to address the coronavirus disease 2019 (COVID-19) outbreak and keep you and your family informed on the latest developments. Here are answers to some frequently asked questions from consumers about vaccines, side effects, and the Vaccine Adverse Event Reporting System.

Q: Why are the FDA and CDC recommending a pause in the use of the Johnson & Johnson (Janssen) COVID-19 vaccine?

A: The FDA and CDC are reviewing data involving 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. The FDA recommended the pause after becoming aware of six cases, of the nearly 7 million doses administered so far in the United States. One person died. All cases occurred in women ages 18 to 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 we 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 in place to monitor COVID-19 vaccines is working. We were able to detect the reports of these very rare, serious adverse events early and take action. The FDA and CDC will continue to fully investigate all reports to determine if a causal relationship exists. For more information, visit this CDC page.

Q: If I received the Johnson & Johnson (Janssen) COVID-19 vaccine, am I at risk for these adverse events?

A: 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 six to 13 days after vaccination.

Contact your health care provider immediately if you are experiencing any of these 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 after vaccination, which can include headache, fatigue, muscle aches and nausea. Most of these side effects are mild to moderate, and last one to two days.

Q: How do I report COVID-19 vaccine side effects?

A: If you experience a severe allergic reaction or any life-threatening symptoms – such as trouble breathing – call 911, or go to the nearest hospital.

Call the vaccination provider or your health care provider if you have any side effects that bother you or do not go away.

Report vaccine side effects to the FDA/CDC Vaccine Adverse Event Reporting System (VAERS) by calling 1-800-822-7967 or going online. Please include the name of the vaccine in the first line of box #18 of the report form.

You may also be given an option to enroll in v-safe. V-safe is a new voluntary smartphone-based tool that uses text messaging and web surveys to check in with vaccinated people to identify potential side effects after COVID-19 vaccination. V-safe asks questions that help CDC monitor the safety of COVID-19 vaccines. V-safe also provides second-dose reminders, if needed, and live telephone follow-up by CDC if participants report a significant health impact following COVID-19 vaccination. For more information on how to sign up, visit: www.cdc.gov/vsafe.

For the latest information about COVID-19, visit:

• FDA: Coronavirus Disease 2019 (COVID-19)
• FDA: COVID-19 Vaccines
• CDC: Coronavirus (COVID-19)
• U.S. Department of Health and Human Services

View Webpage