COVID-19 Vaccine Side Effects

Guidance rapidly changes as we continue to learn more about COVID-19. We encourage you to review the Centers for Disease Control and Prevention’s website for the most updated recommendations.

The side effects from COVID-19 vaccination may feel like flu and might even affect your ability to do daily activities, but they should go away in a few days.

Possible Side Effects from the COVID-19 Vaccine

Common side effects include:
  • sore arm or pain and redness at the injection site
  • swollen lymph nodes in the underarm on the same side as the injection site
  • chills or fever
  • fatigue, body aches or feeling run down
  • headache
  • nausea, vomiting or diarrhea in the first 72 hours
These reactions are frequent and are a sign that might indicate that your body is making an immune response to the vaccine. They should  go away within 1-2 days, with the exception that swollen lymph nodes may persist up to about 10 days.

Tips to Help You Identify and Minimize Mild Side Effects:

  • Read the Vaccine Information that came with your scheduling invite to refresh your knowledge about side effects. 
  • Use an ice pack or cool, damp cloth to help reduce redness, soreness and/or swelling at the place where the shot was given.
  • A cool bath can also be soothing.
  • Drink plenty of liquids for 1-2 days after getting the vaccine.
  • Take an over the counter pain reliever unless you have any specific contraindication.
  • The Center for Disease Control and Prevention (CDC)’s “v-safe” after vaccination health checker is a smartphone-based tool that you can use to quickly tell the CDC if you have any side effects. Participation is voluntary and not a substitute for medical care. 

When to Call the Campus COVID Resource Line (CCRL)

If your symptoms are severe or last more than 72 hours, call 203-432-6604 (or 866-924-9253) 8:30 am - 5:00 pm, 7 days a week.

When You Might Need to be Tested for COVID-19 Infection

While some of the common side effects are similar to symptoms of  COVID-19, the following symptoms suggest COVID-19 infection and are not caused by the vaccine. If you experience any of these symptoms:
  • New loss of smell or taste
  • Cough or shortness of breath
  • Congestion/sore throat/runny nose/conjunctivitis (red eye)
  • Nausea/vomiting or diarrhea that develops after 72 hours
Stay at home and call your provider or CCRL to schedule a COVID-19 test. 

Johnson & Johnson COVID-19 Vaccine Rare and Serious Adverse Event

A rare and serious adverse event (blood clots with low platelets) has been associated with the J&J vaccine. This adverse event is very rare affecting about 7 per 1 million vaccinated women between 18 and 49 years old. The rate is even lower in other populations. Women younger than 50 years old should be aware of the rare but increased risk of this adverse event and that there are other COVID-19 vaccine options available for which this risk has not been seen. The CDC and FDA will continue to monitor the safety of all COVID-19 vaccines.

Women between 18 and 49 years old who received the J&J vaccine are encouraged to follow this guidance:

If you have received the J&J vaccine be aware of possible symptoms of a blood clot with low platelets within three weeks of receiving the vaccine. These include:

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

Seek medical care right away if you develop one or more of these symptoms.