[Contact allergy to beta blockaders in eye drops: cross allergy?].

INTRODUCTION

Beta-blockers in eye-drops are widely used for the treatment of glaucoma. The potential allergic effect was only recently recognized.

CASE REPORT

A 65-year-old man had been treated with eye-drops containing beta-blockers for bilateral chronic glaucoma for 14 years. During the last two years, he developed eczema localized on the upper and lower eyelids. Allergy screening confirmed the implication of timolol and befunolol which had been used successively. Later prescription of eye-drops containing carteolol led to recurrence of the eczema.

DISCUSSION

This case of contact allergy with three different beta-blockers in the same patient is similar to others reported in the literature. All beta-blockers have a similar chemical structure, but it cannot act as a haptene. The proposed hypothesis is a cross-sensitivity which develops after primary metabolism to a common aldehyde. The risk of recurrence is high if another beta-blocker eye-drop compound is prescribed in a sensitized patient. The risk of side effects in such sensitized patients when taking oral beta-blockers is unknown.