Hemoptysis or coughing out of blood may be due to any of the following: irritation of the throat from violent coughing, blood clot in the lung, bronchiectasis, bronchitis, cancer, cystic fibrosis, inflammation of the blood vessels in the lung, nosebleeds, pneumonia, tuberculosis or inhaling blood into the lungs. Are there any other signs or symptoms present? Chest x-ray, complete blood count and complete medical and physical examination is needed to help with the diagnosis. It would be best to see your doctor to rule out any differentials and to reach a complete diagnosis.
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Why I vomit blood from my throat