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Haemophilus b conjugate (prp-omp) vaccine Side Effects

For the Consumer

Applies to haemophilus b conjugate (prp-omp) vaccine: intramuscular suspension

Get emergency medical help if your child has signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Keep track of any and all side effects your child has after receiving this vaccine. When the child receives a booster dose, you will need to tell the doctor if the previous shot caused any side effects.

Becoming infected with haemophilus B is much more dangerous to your child's health than receiving this vaccine. Like any medicine, this vaccine can cause side effects but the risk of serious side effects is extremely low.

Call your doctor at once if your child has:

  • high fever (within a few hours or a few days after the vaccine);

  • seizure (blackout-out or convulsions); or

  • fussiness, irritability, crying for an hour or longer.

Common side effects may include:

  • diarrhea; or

  • pain, swelling, or redness where the shot was given.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects.

For Healthcare Professionals

Applies to haemophilus b conjugate (prp-omp) vaccine: intramuscular suspension


Gastrointestinal side effects have included vomiting and diarrhea.[Ref]


General side effects have included fever greater than 38.3°C (101°F) rectal, crying, unusual high-pitched crying, prolonged crying (more than 4 hours), and otitis media. There have been postmarketing reports of lymphadenopathy.[Ref]


Local side effects have included local pain, redness, swelling, tenderness at the injection site. There have been postmarketing reports of lymphadenopathy and sterile injection site abscess.[Ref]

Nervous system

Nervous system side effects have included irritability, drowsiness, and lethargy. There have been postmarketing reports of febrile seizures.[Ref]


Respiratory side effects have included upper respiratory infection.[Ref]


Hypersensitivity side effects have included rare reports of angioedema.[Ref]


Dermatologic side effects have included rash.[Ref]


1. "Product Information. Liquid PedvaxHIB (haemophilus b conjugate (PRP-OMP) vaccine)." Merck & Company Inc, West Point, PA.

Some side effects of haemophilus b conjugate (prp-omp) vaccine may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.

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