Immunization Reactions

Pediatric HouseCalls Online

DEFINITION

• You believe your child is having a reaction to a recent immunization.
• Reactions to DTaP (Diphtheria, Tetanus, Pertussis), MMR (Measles, Mumps, Rubella), polio, Hemophilus influenzae type b, Hepatitis A, Hepatitis B, Influenza, Chickenpox (varicella)), pneumococcal and meningococcal vaccines are covered.

Symptoms

• Most local swelling, redness and pain at the injection site begins within 24 hours of the shot. It usually lasts 2 to 3 days, but with DTaP can last 7 days.
• Fever with most vaccines begins within 24 hours and lasts 2 to 3 days.
• With live vaccines (MMR and chickenpox), fever and systemic reactions usually begin between 1 and 4 weeks.
• Severe allergic reactions are very rare, but can occur with any vaccine.

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WHEN TO CALL YOUR DOCTOR

Call 911 Now (your child may need an ambulance) If

• Difficulty with breathing or swallowing.
• Not moving or very weak.  
• Unresponsive or difficult to awaken .

Call Your Doctor Now (night or day) If

• Your child looks or acts very sick
• Age under 12 weeks with fever above 100.4° F (38.0° C) rectally (Caution: Do NOT give your baby any fever medicine before being seen.)
• Fever over 104° F (40° C) and not improved 2 hours after fever medicine
• High-pitched, unusual crying present over 1 hour
• Crying continuously for over 3 hours
• Redness or red streaking around the injection site begins over 48 hours (2 days) after the shot
• Redness or red streak around the injection site becomes larger than 1 inch

Call Your Doctor Within 24 Hours (between 9am and 4pm) If

• You think your child needs to be seen
• Fever present for more than 3 days
• Measles vaccine rash (onset day 6 to 12) persists over 3 days

Call Your Doctor During Weekday Office Hours If

• You have other questions or concerns
• Pain, tenderness, redness or swelling at the injection site persists over 3 days
• Fussiness from vaccine persists over 3 days

Parent Care at Home If

• Normal immunization reaction and you don't think your child needs to be seen.

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HOME CARE ADVICE FOR IMMUNIZATION REACTIONS

Treatment for Common Immunization Reactions

1. Local Reaction at Injection Site:
   • Cold Pack: For initial pain or tenderness at the injection site with any vaccine, apply a cold pack or ice in a wet washcloth to the area as needed.
   • Pain Medicine: Give acetaminophen (e.g., Tylenol) or ibuprofen by mouth. (See Dosage table)
   • Localized Hives: Apply 1% hydrocortisone cream OTC once or twice.
2. Fever:
   • Fever with most vaccines begins within 24 hours and lasts 2 to 3 days.
   • For fevers above 102° F (39° C), give acetaminophen every 4 hours (If over 6 months old, okay to give ibuprofen every 6 hours) (See Dosage table)
   • For all fevers: Give cold fluids in unlimited amounts. Avoid excessive clothing or blankets (bundling).
3. General Reaction:
   • All vaccines can cause mild fussiness, irritability and restless sleep. While this is usually due to a sore injection site, sometimes the cause is less clear.
   • Some children sleep more than usual. A decreased appetite and activity level are also common.
   • These symptoms do not need any treatment and will usually resolve in 24-48 hours.
4. Call Your Doctor If:
   • Fever lasts over 3 days
   • Pain lasts over 3 days
   • Redness or swelling lasts over 3 days
   • Your child becomes worse

Specific Immunization Reactions

1. Chickenpox Vaccine:
   • Pain or swelling at the injection site for 1 to 2 days (in 19% of children)
   • Mild fever lasting 1 to 3 days begins 17 to 28 days after the vaccine (in 14%). Give acetaminophen or ibuprofen for fever over 102° F (39°C).
   • Never give aspirin for fever, pain or within 6 weeks of receiving the vaccine (Reason: risk of Reye's syndrome - a rare but serious brain disease)
   • Chickenpox-like vaccine rash (usually 2 lesions) at the injection site (in 3%)
   • Chickenpox-like vaccine rash (usually 5 lesions) scattered over the body (in 4%)
   • This mild rash begins 5 to 26 days after the vaccine and usually lasts a few days.
   • Children with these vaccine rashes can go to day care or school. (Reason: for practical purposes, vaccine rashes are not contagious)
   • EXCEPTION: avoid school if widespread, weepy lesions (Reason: probably actual chickenpox).
   • Precaution: if vaccine rash contains fluid, cover it with clothing or Band-Aid.
2. DTaP or DT Vaccine: The following harmless reactions to DTaP can occur:
   • Pain, tenderness, swelling or redness at the injection site (in 25% of children) and lasts for 24 to 48 hours.
   • Fever (in 25% of children) and lasts for 24 to 48 hours
   • Mild drowsiness (30%), fretfulness (30%) or poor appetite (10%) and lasts for 24 to 48 hours.
   • A large swelling over 4 inches (10 cm) arm can follow the 4th or 5th dose of DTaP occurs in 5% of children. Most children can still move the leg or arm normally.
   • The large thigh or upper arm swelling resolves without treatment by day 3 (60%) to day 7 (90%). This is not an allergy and future DTaP vaccines can be given.
3. Hemophilus Influenza Type B Vaccine (Hib):
   • No serious reactions reported
   • Sore injection site or mild fever only occurs in 1.5% of children
4. Hepatitis A Vaccine:
   • No serious reactions reported
   • Sore injection occurs in 20% of children, loss of appetite in 10%, and headache in 5%.
   • Usually no fever.
   • If these symptoms occur, they begin 3-5 days after vaccine and last 1-2 days
5. Hepatitis B Virus Vaccine (HBV):
   • No serious reactions reported
   • Sore injection site occurs in 30% of children and mild fever in 3% of children
   • Because fever from the vaccine is rare, any infant under 2 months with a fever following the vaccine should be examined.
6. Influenza Virus Vaccine:
   • Pain, tenderness or swelling at the injection site occurs within 6 to 8 hours in 10% of children.
   • Mild fever under 103° F (39.5° C) occurs in 18% of children. Fevers mainly occur in young children.
   • Nasal Influenza Vaccine: No side effects, no fever or symptoms.
7. Measles Vaccine:
   • The measles vaccine can cause a fever (10% of children) and rash (5% of children) about 6 to 12 days following the injection.
   • Mild fever under 103° F (39.5°C) in 10% and lasts 2 or 3 days.
   • The mild pink rash is mainly on the trunk and lasts 2 or 3 days.
   • No treatment is necessary. Your child is not contagious.
   • Call Your Doctor If:
     • Rash becomes very itchy
     • Rash changes to purple spots
     • Rash lasts over 3 days
8. Meningococcal Vaccine:
   • No serious reactions
   • Sore injection site for 1 to 2 days occurs in 50%, with limited use of the arm in 15%.
   • Mild fever occurs in 4%, headache in 40% and joint pain in 20%
   • The vaccine never causes meningitis.
9. Mumps or Rubella Vaccine: There are no reactions except for an occasional sore injection site.
10. Pneumococcus Vaccine:
    • No serious reactions
    • Pain, tenderness, swelling OR redness at the injection site in 15 - 30%
    • Mild fever under 102° F (39° C) in 15% for 1-2 days
11. Polio Vaccine:
    • Polio vaccine by injection occasionally causes some muscle soreness.
    • Oral vaccine no longer used in the U.S.
12. Rotavirus Vaccine:
    • No serious reactions to this oral vaccine
    • Mild diarrhea or vomiting for 1 to 2 days in 3%
    • No fever
13. Human Papillomavirus Vaccine:
    • No serious reactions reported
    • Sore injection site for few days in 80%
    • Mild redness and swelling at the injection site (in 25%)
    • Fever over 100.4° F (38.0° C) in 10% and fever over 102° F (39° C) in 1-2%.

And remember, contact your doctor if your child develops any of the "Call Your Doctor" symptoms.

Disclaimer: This information is not intended be a substitute for professional medical advice. It is provided for educational purposes only. You assume full responsibility for how you choose to use this information.

Author and Senior Reviewer: Barton D. Schmitt, M.D.

Last Reviewed: 1/19/2009

Last Revised: 6/25/2008

Content Set: Pediatric HouseCalls Online

Copyright 1994-2009 Barton D. Schmitt, M.D.