Management of Post‑MMR Vaccine Urticaria
Timing and Typical Presentation
Pathophysiology
Treatment Recommendations
Systemic Corticosteroids
Antihistamine Therapy
Monitoring for Severe Reactions
Future Vaccination Considerations
Urticaria-like Reaction after MMRV Vaccination: Clinical Management
Nature of the Reaction
- The Centers for Disease Control and Prevention recommends that urticaria after MMR/MPRV vaccination is a rare hypersensitivity reaction, typically consisting of localized or generalized urticaria 3, 4, 5.
- Allergic reactions after these vaccines are generally mild and short-lived, with anaphylactic reactions being extremely rare, occurring at a rate of less than 1 case per million doses distributed 3, 5, 6.
Management
- The American Academy of Pediatrics suggests administering oral antihistamines (such as cetirizine or loratadine) to control itching and urticaria 3, 4.
- Monitor the patient for signs of progression to more severe reactions (respiratory distress, oropharyngeal edema, hypotension) 7, 8, 9.
Componentes of the Vaccine and Allergies
- The gelatin component is the most frequently associated allergen with reactions after MMR/MPRV vaccination, not egg antigens 10, 8, 9.
- The viruses are grown in chicken embryo fibroblasts, but allergic reactions are not correlated with egg antigens 10, 8, 11.
Decision for Future Doses
- If the reaction was only urticaria without anaphylactic symptoms, the second dose of the vaccine can generally be administered, but with precautions 3, 4, 5.
- Consider a skin test for gelatin sensitivity before the next dose if gelatin allergy is suspected 10, 8, 9.