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Liquid PedvaxHIB Side Effects

Generic name: haemophilus b conjugate (prp-omp) vaccine

Note: This document contains side effect information about haemophilus b conjugate (prp-omp) vaccine. Some of the dosage forms listed on this page may not apply to the brand name Liquid PedvaxHIB.

For the Consumer

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


Your child should not receive this vaccine if he or she has ever had an allergic reaction to a haemophilus B or meningococcal vaccine.

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


The most common adverse events were irritability, sleepiness, injections site pain/soreness, injection site swelling, unusual high-pitched crying, prolonged crying (over 4 hours), diarrhea, vomiting, crying, pain, otitis media, rash, and upper respiratory infection.[Ref]


Very common (10% or more): Fever over 38.3C (rectal) (18.1%)

Common (1% to 10%): Unusual high-pitched crying, prolonged crying (over 4 hours), crying, pain[Ref]


Common (1% to 10%): Diarrhea, vomiting

Frequency not reported: Urticaria[Ref]


Common (1% to 10%): Erythema over 2.5 cm diameter, swelling over 2.5 cm diameter, injection site pain/soreness

Postmarketing reports: Sterile injection site abscess[Ref]


Common (1% to 10%): Irritability, sleepiness[Ref]


Common (1% to 10%): Otitis media, upper respiratory infection[Ref]


Common (1% to 10%): Rash

Postmarketing reports: Angioedema[Ref]

Nervous system

Postmarketing reports: Febrile seizures[Ref]


Frequency not reported: Thrombocytopenia[Ref]


Frequency not reported: Tracheitis[Ref]

More about Liquid PedvaxHIB (haemophilus b conjugate (prp-omp) vaccine)

Consumer resources

Professional resources

Related treatment guides


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

Further information

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.