Janssen COVID-19 Vaccine (JNJ-78436735)

Type of vaccine: Viral vector
Learn how viral vector vaccines work
1 shot, received in the muscle of the upper arm
Does not contain: Eggs, Preservatives, Laxatives
Click here for the full list of ingredients
Recommended for ages 18+

Common side effects

In the arm you received the shot: pain, redness, swelling
Throughout your body: tiredness, headache, muscle pain, chills, fever, nausea
Side effects usually start within a day or two of getting vaccinated. May feel like flu symptoms, may affect ability to do daily activities.

Safety Data

In clinical trials, side effects were common within 7 days of getting vaccinated but were mostly mild to moderate.
Side effects were more common in people 18–59 years old compared to people 60 years and older.

How well does the vaccine work?

The J&J vaccine in clinical trials was 66.3% effective at preventing COVID-19 in people who had no evidence of prior infection. People had the most protection 2 weeks after receiving the vaccination.
The vaccine was highly effective at preventing death and hospitalization in people who did become ill.
Evidence suggests the vaccine may provide protection against asymptomatic infection (the infected person does not get sick).