Abstract:Based on the latent phlegm theory and the theory of "accumulation in the stomach and obstruction in the lung, " this article systematically elucidates the core pathogenesis of post-infectious cough as "lung-stomach dysfunction and retention of latent phlegm." It outlines the core therapeutic principle of "treating the lung and stomach to resolve latent phlegm,and resolving latent phlegm to restore lung-stomach function." Corresponding prescriptions and clinical approaches are proposed for syndrome types such as cold phlegm, damp phlegm, and dry phlegm. Clinical cases also validate the effectiveness of diagnosis and treatment guided by this theory,providing theoretical support and practical pathways for traditional Chinese medicine management of post-infectious cough.