Seborrheic dermatitis, also known as seborrheic eczema, is a chronic, superficial inflammatory skin disease characterized by papular and scaly lesions predominantly occurring in areas rich in sebaceous glands such as the head, face, and trunk, often accompanied by varying degrees of itching. The exact causes of the condition are not fully understood, but it is generally believed to be associated with an increase in sebum secretion or changes in its chemical composition, as well as colonization and infection by Malassezia yeast. Factors such as stress, diet, alcohol consumption, and deficiency in B vitamins can also affect the occurrence and development of the disease to different extents. Therefore, there are not many systemic pharmacological treatments available for seborrheic dermatitis clinically. Main treatments include oral administration of vitamin B2, vitamin B6, complex vitamin B, or zinc-containing preparations. Antipruritic sedatives may be administered orally when itching is severe. Oral itraconazole can be used for fungal infections or widespread lesions, and oral tetracycline, erythromycin, etc., can be used for bacterial infections. In severe, widespread cases, or when there is a tendency towards erythroderma, short-term use of steroids may be necessary.