Complications, hospitalization, and death can result from a flu infection, even in otherwise healthy people.Ĭonversely, flu vaccines are safe for most people. SafetyĪlthough people may experience side effects after receiving the flu shot or nasal vaccine, the side effects are less severe than the symptoms of the flu. Researchers have not seen an association between Guillain-Barré syndrome and the nasal vaccine. The side effects may include:Įxperts suggest that these side effects occur because the nasal vaccine contains live, weakened flu virus, as opposed to the inactivated virus in the flu shot.

The nasal flu vaccine contains a live, attenuated virus that may cause some mild symptoms without leading to the flu. People should note that this complication is very rare and that the association is not well-documented. They estimated that the condition affects 1–2 people in every million who get the flu shot. It is a rare condition but occurs more frequently in people who have had the flu shot.Įxperts calculated the risk of developing Guillain-Barré syndrome after getting the flu shot. Guillain-Barré syndrome occurs when the immune system attacks the nervous system. While not all experts agree, some evidence points to a small association between the flu shot and Guillain-Barré syndrome. However, this is uncommon, and it is typically a reaction to the injection process rather than the flu shot specifically. Sometimes, people may faint after receiving an injection, including the flu shot. Anyone experiencing this symptom can treat it with over-the-counter medication.

The presence of a low grade fever after receiving a vaccination is a sign that the immune system is working. The cells of the immune system, which include lymphocytes and leukocytes, function better at a slightly higher body temperature. Other possible side effects of the flu shot include:Īlthough it is uncommon, some people, especially children, may develop a low grade fever after vaccination, which is a response of the immune system. The side effects that most commonly occur with the injectable flu shot are local soreness, discoloration, and swelling at the injection site. These may differ from person to person and depending on the form of the vaccine. Some people may experience side effects after receiving the flu vaccine. Share on Pinterest JGI/Jamie Grill/Getty Images

Flu shot side effect