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Syncope after immunization
M M Braun1, P A Patriarca, S S Ellenberg
1Center for Biologics Evaluation and Research, Food and Drug Administration, Rockville, Md, USA.
Archives of Pediatrics & Adolescent Medicine
|March 1, 1997
Summary
Syncope after immunization is common, especially in young females, often occurring within 30 minutes. Careful observation post-vaccination can prevent injuries from fainting.
Area of Science:
- Immunology
- Neurology
- Public Health
Background:
- Syncope, or fainting, can occur after immunization.
- Understanding its characteristics and associated injuries is crucial for patient safety.
Purpose of the Study:
- To detail the characteristics, clinical presentation, and morbidity of syncope following immunization.
- To identify risk factors and timing of post-vaccination syncope.
Main Methods:
- A large case series analysis of syncope reports in the United States from 1990-1995.
- Data sourced from the Vaccine Adverse Event Reporting System (VAERS) and National Vaccine Injury Compensation Program.
Main Results:
- 697 cases of syncope post-vaccination were reported, predominantly in individuals under 20 (77.4%) and females (57.5%).
- Most syncope events (97.8%) occurred within 30 minutes of vaccination, with 63.2% within 5 minutes.
- Injuries, including skull fractures, occurred in 6 patients following falls within 15 minutes post-vaccination.
Conclusions:
- Syncope and associated injuries after immunization are preventable in many cases.
- Healthcare providers should monitor patients for presyncopal symptoms and assist them to sit or lie down post-vaccination.
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