Influenza A virus vaccine, h1n1, inactivated (Injection)


Influenza A Virus Vaccine, H1N1, Inactivated (in-floo-EN-za AY VYE-rus VAX-een, H1N1, in-AK-ti-vay-ted)

Keeps you from getting sick with an influenza A (H1N1) 2009 virus ("catching the flu").

Brand Name(s)

When This Medicine Should Not Be Used

How to Use This Medicine


  • Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given as a shot into one of your muscles.
  • A nurse or other health provider will give you this medicine.

If a dose is missed:

  • Most people need only one dose of this medicine.
  • If your child needs a second dose of this medicine, it is very important for your child to receive the second dose on schedule. If you must cancel the appointment for the second dose, make another appointment as close to that date as possible.

Drugs and Foods to Avoid

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Make sure your doctor knows if you are using any medicine that weakens the immune system (such as steroids, cancer treatments, or radiation).

Warnings While Using This Medicine

  • Make sure your doctor knows if you are pregnant or breastfeeding, or if you have HIV or AIDS, cancer, problems with your immune system, or a history of Guillain-BarrĂ© syndrome (a severe nerve and muscle problem).
  • This vaccine may cause a serious type of allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Tell your doctor right away if you have a rash, itching, swelling of the tongue and throat, or trouble with breathing after you get the injection.
  • Avoid people who are sick or have infections.
  • This medicine will not treat flu symptoms if you already have the virus.

Possible Side Effects While Using This Medicine

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Fever, chills, cough, sore throat, and body aches.
  • Severe headache.
  • Unusual tiredness or weakness.

If you notice these less serious side effects, talk with your doctor:

  • Back, muscle, or joint pain.
  • Diarrhea, nausea, or vomiting.
  • Mild headache.
  • Pain, redness, swelling, or tenderness where the shot was given.
  • Stuffy or runny nose
  • Sweating.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Version Info

  • Last reviewed on 9/4/2017

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