Cough and phlegm after a cold, which is one of the main symptoms of upper respiratory tract infection, can be treated and relieved in the following ways: 1. When there is phlegm not easily discharged, it can be treated by taking oral phlegm-reducing drugs, such as aminoglutethimide hydrochloride, acetylcysteine capsules, etc. If combined with bacterial infection, antibiotic treatment can be given, such as cefixime or amoxicillin. 2. Some food therapy methods to relieve, for example, can drink ice sugar stewed pear, etc., can play a role in relieving cough and resolving phlegm. If the cough with phlegm does not improve after the cold, it is recommended that patients go to the hospital in time to prevent bronchitis or pneumonia.