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"What would cause one to cough up blood?"


I've had a persistent, wet cough for some weeks. I'm a healthy, young guy and it didn't seem that bad. So I was pretty surprised last night when I coughed up a little blood. What could possibly cause this? Should I get to a doctor or can I wait and see? It wasn't much blood..


Coughing up blood can happen for a number of different reasons and can be a sign of serious underlying disease. It is best evaluated and treated by a primary care physician or pulmonologist (lung doctor). Coughing up blood can be caused by many different infections, including pneumonia, bronchitis, and tuberculosis.

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It can also be due to problems with the blood clotting in the lungs, either when the blood clots too easily or not well enough and is too thin. Sometimes heart disease causes too much fluid to accumulate in the lungs and leads to coughing up blood. However, the most concerning and serious cause of coughing up blood is lung cancer. To differentiate between the different causes, a full evaluation is warranted. Your doctor will want to know how much and how often you are coughing up blood as well as any problems with your breathing and your heart. It is not possible to come to a diagnosis without examining the patient. It is therefore recommended that you see your primary care physician or get a referral to a pulmonologist.

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