The causes of throat itching and coughing while sleeping are chronic inflammation of the mucous membrane and allergic diseases, as follows: 1. Chronic inflammation of the mucous membrane: Patients may have more talking with their voices or even shouting during the day, which can easily cause chronic inflammation of the mucous membrane of the throat. 2. Allergic diseases: Some patients may have a certain degree of allergic disease in the throat, which may also cause recurrent itching and cough symptoms. It is necessary to actively take symptomatic treatment and improvement measures, and to reasonably use throat-clearing and pharyngeal Chinese medicines, as well as anti-allergic and cough-suppressing drugs.