Based on the theory of"body fluid and blood sharing the same origin",this paper reveals that the core pathogenesis of atopic dermatitis(AD)lies in the abnormal distribution and transformation of body fluid and blood,which is closely related to dysfunction of the lung,spleen,and kidney.Integrating modern medical research on immune regulation and skin barrier function,we propose that in the early stage of AD,due to deficient endowment,acquired loss of nutrition,insufficiency of the spleen and kidney,and failure of the lung-defense system to protect,external pathogens stagnate in the fleshy exterior.This leads to dysfunction of the lung's governance over the skin,impaired distribution of body fluid,obstruction of qi and blood circulation,and stagnation in the skin,resulting in exudative dampness.The dampness stagnates and transforms into heat.Acupuncture should primarily focus on clearing the lung,dispersing stagnation,distributing body fluid,and unblocking collaterals.In the middle and late stages,as lung disease affects the spleen and kidney,acupuncture should emphasize supplementing and tonifying the spleen and kidney,nourishing blood,and moistening dryness,while simultaneously addressing both the root and the branch.For intractable pruritus,fire needling or pricking-collateral cupping can be employed to control itching and reduce recurrence.