FluMist Side Effects

Generic name: influenza virus vaccine, live

Medically reviewed by Drugs.com. Last updated on Dec 3, 2023.

Note: This document provides detailed information about FluMist Side Effects associated with influenza virus vaccine, live. Some dosage forms listed on this page may not apply specifically to the brand name FluMist.

Applies to influenza virus vaccine, live: nasal spray.

In 1976, a number of people who received the “swine flu” influenza vaccine developed Guillain-Barré syndrome (GBS), which is a disease that may cause paralysis. Most of these people were over 25 years of age. Although only 10 out of every one million people who received the vaccine actually developed GBS, this number was 6 times higher than would normally have been expected. Most of the people who got GBS recovered completely.

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

Serious side effects of FluMist

Along with its needed effects, influenza virus vaccine, live (the active ingredient contained in FluMist) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor or nurse immediately if any of the following side effects occur while taking influenza virus vaccine, live:

More common side effects

• chills
• cough
• decreased appetite
• fever
• headache
• muscle aches
• sore throat
• stuffy or runny nose
• tiredness or weakness

Less common side effects

• earache
• pain or tenderness around the eyes and cheekbones
• redness or swelling in the ear
• shortness of breath or troubled breathing
• sneezing
• tightness of the chest or wheezing

Rare side effects

• difficulty with breathing or swallowing
• hives
• itching, especially of the feet or hands
• reddening of the skin, especially around the ears
• swelling of the eyes, face, or inside of the nose
• unusual tiredness or weakness (sudden and severe)

Incidence not known

• anxiety
• bloody nose
• blue or pale skin
• chest pain, possibly moving to the left arm, neck, or shoulder
• confusion
• diarrhea
• dizziness
• drowsiness
• fast heartbeat
• general feeling of illness
• hoarseness
• inability to move the arms and legs
• irritation
• itching
• joint pain, stiffness, or swelling
• nausea
• puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
• severe headache
• skin rash
• stiff neck and/or back
• sudden numbness and weakness in the arms and legs
• swelling or puffiness of the face
• unusual drowsiness, dullness, tiredness, weakness, or feeling of sluggishness
• unusual tiredness or weakness
• vomiting
• weakness of the muscles in your face

Other side effects of FluMist

Some side effects of influenza virus vaccine, live may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common side effects

• abdominal or stomach pain
• irritability
• loss of appetite

Incidence not known

• welts

For healthcare professionals

Applies to influenza virus vaccine, live: nasal spray.

General adverse events

The most commonly reported side effects included runny nose/nasal congestion, cough, headache, and tiredness/weakness.^[Ref]

Cardiovascular

• Postmarketing reports: Pericarditis^[Ref]

Dermatologic

• Uncommon (0.1% to 1%): Facial edema, rash, urticaria^[Ref]

Gastrointestinal

• Very common (10% or more): Abdominal pain (up to 12%)
• Postmarketing reports: Diarrhea, nausea, vomiting^[Ref]

Hypersensitivity

• Uncommon (0.1% to 1%): Hypersensitivity reactions
• Very rare (less than 0.01%): Anaphylactic reactions^[Ref]

Metabolic

• Very common (10% or more): Decreased appetite (up to 21%)^[Ref]

Musculoskeletal

• Very common (10% or more): Myalgia/muscle aches (up to 17%)
• Common (1% to 10%): Chills^[Ref]

Nervous system

• Very common (10% or more): Tiredness/weakness (up to 26%), fever greater than 100F (up to 16%), decreased activity/lethargy (up to 14%), malaise
• Common (1% to 10%): Fever of greater than 100 to up to 101F, fever of greater than 101F to up to 102F, hospitalizations, otitis media^[Ref]

Other

• Very common (10% or more): Tiredness/weakness (26%), fever (16%)
• Common (1% to 10%): Hospitalizations, otitis media^[Ref]

Psychiatric

• Very common (10% or more): Irritability (up to 21%)^[Ref]

Respiratory

• Very common (10% or more): Runny nose/nasal congestion (up to 58%), sore throat (up to 28%), cough (up to 14%)
• Common (1% to 10%): Sinusitis, wheezing
• Uncommon (0.1% to 1%): Epistaxis^[Ref]

In a clinical trial among children 6 to 23 months of age, wheezing requiring bronchodilator therapy or with significant respiratory symptoms occurred in 5.9% of FluMist recipients compared to 3.8% of active control recipients (Relative Risk 1.5, 95% CI: 1.2, 2.1). Wheezing was not increased in children 24 months of age and older.^[Ref]

Frequently asked questions

• How and where is a flu shot injection given?
• What flu vaccine can I use with an egg allergy?
• FluMist or Flu Shot: Which is more effective?
• How well does the flu vaccine work?
• How can I get a flu vaccine without a needle?
• Where can I get the flu vaccine right now?
• Can I get FluMist and the COVID vaccine at the same time?
• Which flu vaccines are available?
• When is the best month to get the flu vaccine?

Further information

FluMist side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

Medical Disclaimer