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Other drug names: A-Am An-Az B C-Ch Ci-Cz D-Dh Di-Dz E F G H I-J K-L M-Mh Mi-Mz N-Nh Ni-Nz O P-Pl Pm-Pz Q-R S-Sn So-Sz T-To Tp-Tz U-V W-Z 0-9   

Influenza Virus Vaccine (Systemic)

Brand Names

In the U.S.-

  • FluMist
  • FluShield
  • Fluvirin
  • Fluzone

In Canada-

  • Fluviral
  • Fluviral S/F
  • Fluzone

Another commonly used name is flu vaccine.


  • Immunizing agent, active


Influenza (in-floo-EN-za) virus vaccine is used to prevent infection by the influenza viruses. The vaccine works by causing your body to produce its own protection (antibodies) against the disease. It is also known as a ****œflu shot." New for the 2003-2004 flu season, influenza virus vaccine is also available as a nasal spray.

There are many kinds of influenza viruses, but not all will cause problems in any given year. Therefore, before the influenza vaccine for each year is produced, the World Health Organization (WHO) and the U.S. and Canadian Public Health Services decide which influenza viruses will be most likely to cause influenza infection that year. Then they include the antigens (substances that cause protective antibodies to be formed) to these viruses in the influenza vaccine made available. Usually, the U.S. and Canada use the same influenza vaccine; however, they are not required to do so.

It is necessary to receive an influenza vaccine injection each year, since influenza infections are usually caused by different kinds of influenza viruses each year and because the protection gained by the vaccine lasts less than a year.

Influenza is a virus infection of the throat, bronchial tubes, and lungs. Influenza infection causes fever, chills, cough, headache, and muscle aches and pains in your back, arms, and legs. In addition, adults and children weakened by other diseases or medical conditions and persons 50 years of age and over, even if they are healthy, may get a much more serious illness and may have to be treated in a hospital. Each year thousands of people die as a result of an influenza infection.

The best way to help prevent influenza infection is to get an influenza vaccination each year, usually in early November. Immunization (administration of vaccine) against influenza is approved for infants 6 months of age and over, all children, and all adults.

Influenza virus vaccine may not protect all persons given the vaccine.

This vaccine is to be administered only by or under the supervision of your doctor or other health care professional. It is available in the following dosage form:

  • Nasal solution (U.S.)
  • Injection (U.S. and Canada)

Before Using This Medicine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For influenza vaccine, the following should be considered:

Allergies- Tell your doctor if you have ever had any unusual or allergic reaction to influenza vaccine or to antibiotics, such as gentamicin, streptomycin, or other aminoglycosides. Influenza vaccine available in the U.S. or Canada may contain these antibiotics in very small amounts. Also tell your health care professional if you are allergic to any other substances, such as foods (especially eggs) or preservatives (especially sodium bisulfite or thimerosal). Influenza vaccine is grown in the fluids of chick embryos.

Pregnancy- Influenza vaccine (****œshot") has not been shown to cause birth defects or other problems in humans.

The nasal mist vaccine should not be given to a pregnant women.

Breast-feeding- Influenza vaccine (****œshot") has not been reported to cause problems in nursing babies.

The nasal mist vaccine may cause viral shedding in the mother. This shedding could infect the infant while breast-feeding.

Children- Use is not recommended for infants up to 6 months of age . In addition, only a split-virus influenza vaccine (****œshot") should be given to children 6 months to 12 years of age. Some side effects of the vaccine, such as fever, unusual tiredness or weakness, or aches or pains in muscles, are more likely to occur in infants and children, who are usually more sensitive than adults to the effects of influenza vaccine.

The nasal mist vaccine should not be used in children less than 5 years of age.

Older adults- This vaccine (****œshot") is not expected to cause different side effects or problems in older persons than it does in younger adults. However, elderly persons may not become as immune to head and upper chest influenza infections as younger adults, although the vaccine may still be effective in preventing lower chest influenza infections and other complications of influenza.

The nasal mist vaccine should not be used in adults 50 years of age and older.

Other medicines- Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your health care professional if you are using any other prescription or nonprescription (over-the-counter [OTC]) medicine.

When you are taking the nasal mist influenza vaccine it is especially important that your health care professional knows if you are taking any of the following:

  • Aspirin therapy or
  • Aspirin-containing therapy-Use of nasal mist influenza vaccine and aspirin or aspirin-containing products in children and adolescents (5 to 17 years of age) in not recommended. These medications may cause Reye syndrome.
  • Immunosuppressive therapies such as:
    • Alkylating dugs (treat some kinds of cancer) or
    • Antimetabolite drugs (treat some kinds of cancer) or
    • Corticosteroids (a cortisone-like medicine) or
    • Immunosuppressive therapy (reduce the body's natural immunity) or
    • Radiation therapy (treat some kinds of cancer)-Use of nasal mist influenza vaccine is not recommended.

Other medical problems- The presence of other medical problems may affect the use of influenza vaccine. Make sure you tell your doctor if you have any other medical problems, especially:
  • Asthma, bronchitis, pneumonia, or other illness involving lungs or bronchial tubes-Use of influenza vaccine (nasal mist or ****œshot") may make the condition worse
  • Immune deficiency diseases such as:
    • Agammaglobulinemia or
    • Cancer or
    • Human immunodeficiency virus infection (HIV) or
    • Immunodeficiency or
    • Leukemia or
    • Lymphoma or
    • Thymus gland problems-Use of live virus vaccines like nasal mist influenza vaccine is not recommended for patients with these medical problems.
  • Guillain Barré syndrome, history of-Use of influenza vaccine (nasal mist or ****œshot") may cause a recurrence of the symptoms of the condition
  • Medical conditions that may make influenza infection more severe, such as:
    • Blood problems (hemoglobinopathies) or
    • Diabetes Mellitus (sugar diabetes) or
    • Heart disease (history of) or
    • Immunosuppression (inability of body to fight an infection) or
    • Kidney disease (history of) or
    • Lung disease (history of) or
    • Metabolic problems (history of)-Use of nasal mist influenza virus vaccine is recommended. Your doctor will decide if use of inactivated influenza virus vaccine (****œshot") is right for you.
  • Severe illness with fever-Influenza virus vaccine should not be given when a fever is present. Your doctor will decide when you are well enough to get your influenza virus vaccine.

Proper Use of This Medicine


The dose of influenza vaccine will be different for different patients. Follow your doctor's orders . The following information includes only the average dose of influenza vaccine.

  • For nasal dosage form:
    • To help prevent influenza infection:
      • Adults and children age 9 through 49 years-One dose (0.5 mL) each year.
      • Children 5 through 8 years of age-One or two doses (0.5 mL), depending on whether the child has received nasal mist influenza vaccine in the past. The dose is given each year. If two doses are needed, they should be spaced 6 weeks apart.
  • For injection dosage form:
    • To help prevent influenza infection:
      • Adults and children 9 years of age and older-One injection each year.
      • Children 6 months to 9 years of age-One or two injections, depending on whether the child has received influenza vaccine in the past. The dose is given each year. If two doses are needed, they should be spaced 4 weeks apart.

Side Effects of This Medicine

Side Effects of This Vaccine

In 1976, a number of persons who received the ****œswine flu" influenza vaccine developed Guillain-Barré syndrome (GBS). Most of these persons were over 25 years of age. Although only 10 out of one million persons receiving the vaccine actually developed GBS, this number was 6 times more than would normally have been expected. Most of the persons who got GBS recovered completely from the paralysis it caused.

It is assumed that the ****œswine flu" virus included in the 1976 vaccine caused the problem, but this has not been proven. Since that time, the ****œswine flu" virus has not been used in influenza vaccines, and there has been no recurrence of GBS associated with influenza vaccinations.

Along with its needed effects, a vaccine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

if any of the following side effects occur:

  • Symptoms of allergic reaction
    • Difficulty in breathing or swallowing;  hives;  itching, especially of feet or hands;  reddening of skin, especially around ears;  swelling of eyes, face, or inside of nose;  unusual tiredness or weakness (sudden and severe) 

Other side effects may occur that usually do not need medical attention. These side effects generally do not last for more than 1 or 2 days. However, check with your doctor if any of the following side effects continue or are bothersome:

  • More common
    • Headache (nasal mist);  nasal congestion (nasal mist);  runny nose (nasal mist);  tenderness, redness, or hard lump at place of injection (****œshot")  

  • Less common
    • Abdominal pain (nasal mist);  aches or pains in muscles;  cough (nasal mist);  diarrhea (nasal mist);  earache (nasal mist);  fever ;  or general feeling of discomfort or illness 

  • pain or tenderness around eyes and cheekbones (nasal mist);  redness or swelling in ear (nasal mist) 

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.

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Last updated: Tue, 06 Jan 2009 00:20:03 GMT