Response:

Coughing up rust-colored phlegm for about a month is a symptom that should not be ignored, especially given your 10-year smoking history. Rust-colored phlegm often indicates old, oxidized blood mixed in with respiratory secretions. This is an important symptom that may signal acute bronchitis, pneumonia, bronchiectasis, tuberculosis, or even just mucosal damage from persistent coughing. A persistent cough lasting more than 3 weeks is one of the symptoms of lung cancer, especially when accompanied by coughing up blood, shortness of breath, chest pain, unexplained weight loss, or prolonged fatigue.

Doctor Ngan examines a patient. *Illustrative photo: Tam Anh General Hospital*

You should seek medical attention if you experience additional symptoms such as unexplained weight loss, gradually worsening dull chest pain, shortness of breath, hoarseness, coughing up blood, prolonged fatigue, or swollen lymph nodes in the neck area. A doctor may order diagnostic tests like X-rays or low-dose computed tomography (LDCT) to evaluate lung tissue clearly and detect any abnormal nodules. Additionally, sputum tests, bronchoscopy, or other specialized tests may be considered.

You should not self-medicate with antibiotics or cough suppressants without a clear diagnosis. At 40 years old, and with a 10-year smoking history, you are in a high-risk group. Therefore, regular lung cancer screening using low-dose computed tomography is recommended to detect the disease at an early stage. If abnormal images appear on the scans, your doctor will order additional necessary exploratory tests to obtain accurate results.

Doctor Nguyen Van Ngan

Department of Respiratory Medicine

Tam Anh General Hospital Ha Noi

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