Possible anaphylactic reactions following administration. Increased risk of wheezing following administration in childn <5 yr w/ recurrent wheezing & persons of any age w/ asthma. Carefully consider potential benefits & risks when deciding to administer FluMist Quadrivalent if Guillain-Barré syndrome has occurred w/in 6 wk of any prior influenza vaccination. Persons w/ severe asthma or active wheezing. Immunocompromised persons. Individuals w/ underlying medical conditions that may predispose them to complications following wild-type influenza infection. Not approved for use in childn <2 yr & elderly ≥65 yr.