Immediate allergic reactions after vaccinations – a post-marketing surveillance review

Abstract.

Immediate systemic allergic reactions after vaccination with commonly used vaccines are very rare. Consequently, the risk of these reactions cannot be verified before widespread use. A data analysis of spontaneously reported suspected adverse drug reactions following the administration of 15 marketed vaccines, from 1994 to 1998, shows an average reporting rate for "allergic" reactions of one case report per 450,000 vaccine doses sold. Of these, potentially life-threatening events are extremely rare. In 31% of our case reports the reaction was reported after the first vaccination. In these cases a pre-sensitisation or a pseudo-allergic reaction can be assumed. There was no evidence for an increased risk of "allergic" reactions for patients with atopy. Conclusion: our data support a high level of safety for the vaccines included in the analysis. They also emphasise the importance of a careful vaccination management after occurrence of "allergic" reactions and the necessity of a post-marketing surveillance system for recording adverse drug reactions.