A Case of Allergic Reaction to 0.5% Moxifloxacin Eye Drops

Purpose: We report a rare case of allergic contact dermatitis after the use of a non-preservative 0.5% moxifloxacin ophthalmic solution.Case summary: A 60-year-old male presented with bacterial corneal ulceration of the right eye. He was treated with 50 mg/mL of fortified cefazolin and 14 mg/mL of tobramycin that were tapered as the corneal lesion improved after 1 month, and 0.5% moxifloxacin application was started. After 2 weeks of moxifloxacin treatment, the patient developed conjunctival injection, lid swelling, redness, and itching in the right eye. An allergic reaction was suspected and moxifloxacin administration was immediately stopped. The symptoms improved after the administration of oral antihistamines, 0.5% loteprednol eye drops, and steroid combination ointment.Conclusions: Patients treated with 0.5% topical moxifloxacin should be monitored for allergic contact dermatitis, even if preservative-free eye drops are used.