Canthal blepharitis, also known as canthal blepharitis, is a common category of blepharitis, in which the lesion is primarily due to infection by the bacterium Moraxella catarrhalis, is mostly bilateral, often occurs in the lateral canthus, is macerated and congested at the lid margin and nearby skin, and often coexists with canthal conjunctivitis. The main symptom of canthal blepharitis is a tingling sensation and discomfort. In treatment, 0.25%-0.5% zinc sulfate eye drops are primarily used, and the lid margins and nearby skin are first coated with 1% brilliant green alcohol, followed by zinc oxide ophthalmic ointment. It is also treated with oral vitamin B complex, especially riboflavin.