influenza vaccine live intranasal; FluMist, FluMist Quadrivalent

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GENERIC NAME: influenza vaccine live, intranasal

BRAND NAME: FluMist, FluMist Quadrivalent

DRUG CLASS AND MECHANISM: FluMist is a nasal vaccine that protects against infection with the influenza virus or the "flu." FluMist contains live influenza virus that has been weakened so that it causes minimal or no symptoms. When FluMist is inhaled, the body responds to the weakened viruses in FluMist by developing antibodies that fight influenza viruses. These antibodies protect against later infections by the naturally-occurring influenza virus. FluMist is effective only against the strains of influenza virus that are included in it, and the strains of virus change from year to year. FluMist has no effect on the flu once infection has begun. FluMist should be given shortly before the flu season begins to allow time for antibodies to be produced and for protection throughout the entire flu season. FluMist and FluMist Quadrivalent are similar except for the addition of one additional virus strain to Flumist Quadrivalent. FluMist is a trivalent vaccine because it has three flu virus strains (two type A viruses and one B type) and FluMist Quadrivalent has four virus strains (two A type and two B types). FluMist and FluMist Quadrivalent do not prevent 2009 H1N1 (swine flu) virus infection. The FDA approved FluMist in June 2003 and FluMist Quadrivalent in February 2012.



PREPARATIONS: Intranasal Spray: prefilled single use intranasal spray, 0.2 ml

STORAGE: FluMist should be stored refrigerated between 2 C to 8 C (35 F to 46 F).

PRESCRIBED FOR: FluMist is used for preventing influenza virus infections (flu) in individuals 2 to 49 years of age.

DOSING: Children 2 to 8 years of age who have not previously received FluMist should be given 2 doses of 0.2 ml at least one month apart. Children 2 to 8 years of age, who previously received FluMist and adults 9 to 49 years of age, should be given 1 dose (0.2 ml) of FluMist each season. FluMist is administered by inhaling through the nose while standing or sitting in an upright position. FluMist is not administered by injection.

Since FluMist contains viruses that are likely to cause the flu in the upcoming season, FluMist developed for previous seasons will not be effective and should not be used.

DRUG INTERACTIONS: Children 5 to 17 years of age who are receiving aspirin therapy should not be given FluMist because of the association between aspirin, influenza infection, and Reye's syndrome, a serious disease of the liver.

Use of FluMist together with antiviral drugs that are active against the influenza virus has not been evaluated. Since there is a potential for antiviral drugs to reduce the effectiveness of FluMist (by preventing infection with the weakened viruses in FluMist), antiviral drugs should not be administered until 2 weeks after FluMist therapy, and FluMist should not be administered until 48 hours after antiviral therapy is discontinued.

Administering FluMist with inactivated virus vaccines was not evaluated in FluMist clinical trials, and combining FluMist with other intranasal products has not been evaluated. FluMist did not interfere with, and was not affected by measles, mumps, rubella, or varicella live vaccines.

PREGNANCY: FluMist should not be given to pregnant women.

NURSING MOTHERS: Use of FluMist during breastfeeding has not been adequately evaluated, and it is not known whether FluMist is excreted in breast milk.

SIDE EFFECTS: The most common side effects of FluMist are cough, runny nose, nasal congestion, sore throat, headache, restlessness, muscle aches, tiredness or weakness and fever. Hypersensitivity reactions also have been reported. FluMist should not be administered to individuals with asthma because it may increase wheezing.


U.S. Food and Drug Administration, Vaccines, Blood & Biologics. "FluMist Quadrivalent." 08/20/2013.

Vaccines, Blood & Biologics. February 29, 2012 Approval Letter - FluMist & Quadrivalent.

Medically Reviewed by a Doctor on 1/27/2014

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