Hi there,
The signs of a severe allergic reaction can include difficulty breathing, hoarseness or wheezing, swelling around the eyes or lips, hives, paleness, weakness, a fast heart beat or dizziness.
Life threatening allergic reactions to the flu shot are rare. Moreveor, should there be one, these signs would most likely happen within a few minutes to a few hours after the vaccine is given.
Otherwise, receiving the flu vaccine is a fairly uncomplicated process. The common side effects that one might attribute to an allergic reaction include soreness, redness, swelling from the shot, headache, fever, nausea and muscle aches.
