Background. We report a patient who developed corneal epithelial disorder repeatedly after changing the prescription from
Xalatan eye drops (Pfizer Inc.) to
Latanoprost eye drops (Kaken
Pharmaceutical Co., Ltd.), both containing 0.005%
latanoprost. Case Report. An 88-year-old male with
glaucoma had been treated with
Timoptol eye drops and
Xalatan eye drops for a few years. While he stayed in a health care facility for the elderly,
Xalatan eye drops was changed to
Latanoprost eye drops usage, and
eye pain developed on the day of this change. On the next day, he visited our department, and corneal epithelial disorder was observed. The drops were discontinued, and the corneal epithelial disorder healed after 2 days. Twenty days after the first consultation,
Xalatan eye drops and
Latanoprost eye drops were resumed by a physician of internal medicine in the health care facility, but
eye pain developed again. After discontinuation of the two drugs,
Xalatan eye drops usage was resumed the next day, but no corneal epithelial disorder was observed thereafter. Conclusions. This clinical history strongly suggested the association between a
generic drug,
Latanoprost eye drops, and the development of corneal epithelial disorder.