- You believe your child is having a reaction to an 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
pneumococcusmeningococcal vaccines are covered.
- Most reactions at the injection site and fever occur within 2 days
and most general reactions or fever within 7 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
WHEN TO CALL YOUR DOCTOR FOR
Call 911 Now (your child may need an ambulance)
with breathing or swallowing.
Not moving or very weak.
Unresponsive or difficult to awaken .
Call Your Doctor Now (night or day) If
looks or acts very sick.
Age less than 12 weeks with fever above 100.4°F (38°C)
rectally. (Exception: occurs within 48 hours after DTaP shot.)
Fever above 104°F.
High-pitched, unusual cry present for more than 1 hour.
Crying continuously for more than 3 hours.
Redness or red streak around the injection site bigger than
Redness around the injection site persists for more than 48
hours (2 days).
Call Your Doctor Within 24 Hours (between 9am and 4pm)
your child needs to be seen.
Fever present for more than 3 days.
Pain, tenderness, or swelling at the injection site persists
for more than 3 days.
Measles vaccine rash (onset day 6 to 12) persists for more than
Call Your Doctor
During Weekday Office Hours If
other questions or concerns.
Parent Care at Home If
immunization reaction and you don't think your child needs to be seen.
HOME CARE ADVICE FOR
- Local Reaction to the
Injection (all vaccines except oral polio):
- Pain: For initial pain or tenderness at the injection
- Apply ice to the area for 20 minutes once.
- Give acetaminophen (e.g. Tylenol) or ibuprofen by mouth.
Fever: For fevers above 102°F (39°C), give acetaminophen
(ok to use ibuprofen if older than 6 months old).
- 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.
Call Your Doctor If
- Fever lasts more than 3 days.
- Pain lasts more than 3 days.
- Injection site starts to look infected.
- Your child becomes worse or develops any of the "Call Your
- Pain or swelling at the injection site for 1 to 2 days (in 19%
- Fever lasting 1 to 3 days begins 17 to 28 days after the vaccine
Give acetaminophen (e.g. Tylenol) or ibuprofen for fever above 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
DTaP or DT Vaccine: The following harmless reactions to DTaP
- Pain, tenderness, swelling or redness at the injection
site (in 25% of children) and lasts for 24 to 48 hours.Swollen arm or leg
following 4th or 5th DTaP occur in 3% and is not
- 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.
Hemophilus influenzae Type b Vaccine(HiB):
No serious reactions reported.
Sore injection site or mild fever only occurs in 1.5% of children.
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.
Hepatitis B Virus Vaccine (HBV):
- No serious reactions reported.
- Sore injection site occurs in 30% of children and mild fever in 3%
- Because fever from the vaccine is rare, any infant less than 3 months
with a fever following the vaccine should be examined.
- Influenza Virus Vaccine:
- Pain, tenderness or swelling at the injection site occurs within
6 to 8 hours in 10% of children.
- Fever 101° to 103°F (38.4° to 39.5°C) occurs
in 18% of children. Fevers mainly occur in young children.
- 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. The fever is usually between
101° and 103°F (38.4° and 39.5°C) 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 more than 3 days.
- Meningococcal Vaccine:
- No serious reactions
- Sore injection site for 1 to 2 days is uncommon
Mumps or Rubella Vaccine:
- There are no reactions except for an occasional sore injection
- Pain, tenderness, swelling OR redness at the injection site
- Mild fever below 102°F (39°C) in 15% for 1-2 days.
- No serious reactions.
- There are no serious reactions to oral polio vaccine. Polio
vaccine by injection occasionally causes some muscle soreness.
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.
Pediatric HouseCalls Online. Copyright © 2000-2004
Barton Schmitt, M.D. FAAP
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