Major Warning Signs You Have Lung Cancer

5. Unexplained Muscle Weakness & Fatigue

Beyond just feeling tired, unexplained muscle weakness and profound fatigue that doesn't improve with rest can be a subtle sign. Lung cancer tumors can release antibodies that inadvertently attack the body's own muscles and nerves, leading to conditions like Lambert-Eaton Myasthenic Syndrome. Furthermore, the body's fight against cancer can deplete energy reserves, or the cancer might affect red blood cell production, leading to anemia. If simple tasks like climbing stairs become unusually challenging, or you experience persistent weakness for no clear reason, this could indicate a deeper problem beyond simple exhaustion.

6. A Chronic, Nagging Cough

A cough is your body's natural defense, but a cough that simply won't quit—lasting eight weeks or more—is the most common symptom of lung cancer. This isn't just a lingering "smoker's cough"; it can affect anyone. The lung cancer cough can be dry or productive (with mucus), occur day or night, and often interferes with sleep. Unlike a typical cough, it doesn't improve with cold remedies or antibiotics. If your cough changes in nature (e.g., becomes deeper, more painful, or produces different-looking mucus), or if it's accompanied by other symptoms like shortness of breath or chest pain, do not dismiss it.