# Allergic Reactions to Brimonidine 0.15%: A Case Series

## TL;DR

This study reports five cases of allergic reactions to brimonidine eye drops, showing symptoms like redness and swelling, but not itchiness.

## Contribution

The paper highlights delayed allergic reactions to brimonidine 0.15% with unique clinical features not previously emphasized.

## Key findings

- Allergic reactions occurred months after starting brimonidine 0.15% in five patients.
- Symptoms included eye redness and swelling, but not itchiness, with bumpy conjunctival chemosis as a distinguishing feature.
- Discontinuation of brimonidine led to rapid improvement in symptoms for all patients.

## Abstract

Topical brimonidine is an effective anti-glaucoma agent and is usually well tolerated. This retrospective case series aimed to demonstrate the clinical features of brimonidine 0.15% (Alphagan P; Irvine, CA: Allergan Inc.) allergy. Five cases were found from one ophthalmologist’s two-year patient records. Patients’ ages ranged from 54 to 80 years. Three patients had ocular diagnoses of well-controlled primary open-angle glaucoma, one had normal-tension glaucoma, and another had ghost cell glaucoma. Brimonidine was combined with other anti-glaucoma medications for nine to 16 months before patients developed eye redness and swelling, which was not distressing. Itchiness was not a prominent symptom. Signs included follicles in the eyelid, bulbar conjunctiva with subtle chemosis, and a bumpy appearance. No patients exhibited marked changes in intraocular pressure during the allergy episode. None of the patients had self-discontinued brimonidine. In all cases, ocular symptoms improved dramatically upon withdrawal. One patient needed additional topical anti-histamine for relief. In brief, brimonidine allergy can occur months after commencement. Unlike other causes of allergic conjunctivitis, patients did not complain of itchiness, and bumpy conjunctival chemosis was a distinguishing feature. Ocular symptoms usually resolved upon cessation of brimonidine.