The most common side effects with Qdenga (which may affect more than 1 in 5 people) are pain and redness at the injection site, headache, muscle pain, feeling generally unwell and weakness. Up to 1 in 10 people may experience fever. These side effects, which are usually of mild to moderate severity and resolve within a few days, are less frequent after the second dose of the vaccine than after the first.

This vaccine must not be used in people who had a hypersensitivity (allergic) reaction to a previous dose of Qdenga. It must also not be used in individuals with a weakened immune system because of a disease, medicines that affect the immune system or HIV infection. The vaccine must not be used in women who are pregnant or breastfeeding.

For the full list of side effects and restrictions of Qdenga, see the package leaflet.