Possible causes of redness in the facial triangle include seborrheic dermatitis and rosacea, which can be helped by topical medications, oral medications, and medical aesthetic treatments. 1. Seborrheic dermatitis: Seborrheic dermatitis is a chronic, recurrent, inflammatory skin disease that occurs on the head, face, chest and back where sebaceous glands are distributed more, which mainly manifests itself as erythema and greasy scales in the nasolabial folds, beard area, and other facial triangular zones, and can be accompanied by more pronounced itching, and can recur. The symptoms can be improved by topical application of salicylic acid ointment, calcium-regulated phosphatase inhibitors (such as tacrolimus ointment, pimecrolimus ointment) and other medications, and for the more serious cases, oral vitamin B, zinc, and small and medium-dose glucocorticosteroids can be used to help treat the disease. 2. Rosacea: Rosacea, also known as rosacea, is mainly characterized by persistent erythema and dilated capillaries on the nose and other areas of the face, and the symptoms of redness in the facial triangle will be aggravated when stimulated by factors such as emotions, sun exposure, exercise, alcohol, spicy food stimulation, etc. The symptoms can be treated by topical antibiotic medications. Topical antibiotic ointment (such as fusidic acid ointment, clindamycin ointment), benzoyl peroxide ointment and other medications can be used to help treatment, and in severe cases, oral tetracyclines (such as doxycycline, minocycline), isotretinoin and other medications are needed to help improve the condition. Medical aesthetic treatments (such as intense pulsed light, LED light, dye laser, etc.) can also help improve the symptoms of redness. Redness in the facial triangle is recommended to consult a doctor in a timely manner to clarify the cause of the problem and then treat the symptoms under the guidance of the doctor, do not self-medication.