Infanrixtetra (Diphtheria Toxoid, Tetanus Toxoid, Pertussis Toxoid, Pertussis Filamentous Haemagglutinin, Pertussis)

Infanrixtetra is used to immunise against bacterial toxins and pathogens within the diphtheria‑tetanus‑pertussis (DTP) disease family.

• Diphtheria: induces antibodies that neutralise diphtheria toxin, preventing severe respiratory and systemic disease.
• Tetanus: stimulates immunity to tetanus toxin, reducing risk of muscle rigidity and spasms after wound exposure.
• Pertussis: generates protective antibodies against Bordetella pertussis antigens, decreasing incidence of whooping cough in children.

• The vaccine contains purified toxoids of diphtheria and tetanus and acellular pertussis antigens, including pertussis toxin, filamentous haemagglutinin and pertactin. After intramuscular injection, antigen‑presenting cells process these proteins, prompting B‑cell activation and production of specific IgG antibodies. The resulting immunological memory enables rapid neutralisation of the respective bacterial toxins and inhibition of bacterial adhesion upon subsequent exposure.

Infanrixtetra may be associated with local and systemic reactions typical of injectable vaccines.

Common Side Effects

• Pain at injection site: mild to moderate discomfort lasting 1–3 days.
• Redness or swelling: localized erythema that resolves within 48 hours.
• Low‑grade fever: temperature up to 38 °C occurring within 24 hours.
• Fatigue: transient tiredness reported after vaccination.
• Headache: mild headache lasting a day or two.

Serious or Rare Side Effects

• Severe allergic reaction (anaphylaxis): rapid onset of hives, airway swelling, hypotension.
• High fever (>40 °C): persistent fever requiring medical evaluation.
• Seizures: rare neurologic events post‑immunisation.
• Guillain‑Barré syndrome: extremely rare demyelinating neuropathy.
• Persistent crying or inconsolable irritability in infants: may indicate a serious reaction.

Before administering Infanrixtetra, healthcare providers should observe the following precautions.

• Contraindication: known severe allergy to any vaccine component, including latex.
• Post‑vaccination observation: monitor the patient for at least 15 minutes for immediate reactions.
• Fever or acute illness: defer vaccination until the child is afebrile and clinically stable.
• Immunocompromised status: assess risk‑benefit, as response may be reduced.
• Previous DTP reaction: evaluate severity before repeat dosing.
• Store at 2‑8 °C: keep refrigerated, protect from light, do not freeze or shake.

Infanrixtetra can interact with other agents that affect immune function or increase the risk of hypersensitivity.

Major Interactions (Avoid)

• Live attenuated vaccines: avoid administration within 4 weeks to prevent interference with immune response.
• Immunoglobulin therapy: concurrent use may diminish vaccine efficacy.
• Systemic corticosteroids (high dose): may suppress antibody formation.

Moderate Interactions (Monitor Closely)

• Antipyretics (acetaminophen, ibuprofen): may mask fever, monitor for underlying reactions.
• Antibiotics: generally safe, but monitor for allergic cross‑reactivity if penicillin allergy present.
• Blood products: schedule vaccination at least 3 months apart to avoid immune interference.