Patch-test reactions to topical anesthetics: retrospective analysis of cross-sectional data, 2001 to 2004.

Abstract

BACKGROUND:

Allergy to topical anesthetics is not uncommon. The cross-reactivity among topical anesthetics and the screening value of benzocaine alone are not well understood.

OBJECTIVES:

The goals for this study were: (1) to evaluate the frequency and pattern of allergic patch-test reactions to topical anesthetics, using North American Contact Dermatitis Group (NACDG) data, and (2) to compare these results to allergen frequencies from other published studies.

METHODS:

The NACDG patch-tested 10,061 patients between 2001 and 2004. In this analysis patients were included who had positive patch-test reactions to one or more of the following: benzocaine, lidocaine, dibucaine, tetracaine, and prilocaine.

RESULTS:

Of patch-tested patients, 344 (3.4%) had an allergic reaction to at least one anesthetic. Of those, 320 (93.0%) had an allergic reaction to only one topical anesthetic. Overall, reactions to benzocaine (50.0%, 172 of 344) were most prevalent, followed by reactions to dibucaine (27.9%, 96 of 344); however, reactions to dibucaine were significantly more frequent in Canada than in the United States (relative risk [RR], 2.31; 95% confidence interval [CI], 1.67-3.20; p < .0001). Of patients reacting to more than one anesthetic, most (79%, 19 of 24) reacted to both an amide and an ester.

CONCLUSIONS:

Of the topical anesthetics tested, benzocaine was the most frequent allergen overall. Over 50% of allergic reactions to topical anesthetics in this study would have been missed had benzocaine been used as a single screening agent. Cross-reactivity patterns were not consistent with structural groups.

• Authors: Erin M Warshaw, Sarah E Schram, Donald V Belsito, Vincent A DeLeo, Joseph F Fowler Jr, Howard I Maibach, James G Marks Jr, C G Toby Mathias, Melanie D Pratt, Robert L Rietschel, Denis Sasseville, Frances J Storrs, James S Taylor, Kathryn A Zug
• Journal: Dermatitis : contact, atopic, occupational, drug (Dermatitis) 2008 Mar-Apr Vol. 19 Issue 2 Pg. 81-5 ISSN: 2162-5220 [Electronic] United States
• PMID: 18413108 (Publication Type: Journal Article)

Chemical References

• Anesthetics, Local
• Prilocaine
• Tetracaine
• Lidocaine
• Dibucaine
• Benzocaine

Topics

• Administration, Topical
• Anesthetics, Local (adverse effects)
• Benzocaine (adverse effects)
• Canada (epidemiology)
• Cross-Sectional Studies
• Dermatitis, Allergic Contact (diagnosis, epidemiology, etiology)
• Dibucaine (adverse effects)
• Female
• Humans
• Lidocaine (adverse effects)
• Male
• Middle Aged
• Patch Tests
• Predictive Value of Tests
• Prilocaine (adverse effects)
• Retrospective Studies
• Risk Factors
• Tetracaine (adverse effects)
• United States (epidemiology)