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"What causes blood to appear in one's phlregm?"

ZocdocAnswersWhat causes blood to appear in one's phlregm?


This morning I spat into my bathroom sink and found a small amount of blood in my phlegm. This was pretty disconcerting. What conditions or types of illness can cause blood to appear in one's mucus?


First of all, I wouldn't be too worried about small amounts or streaks of blood in your phlegm especially if this has only happened one or rarely. There are many potential causes for this. Some of the most common include rupture of small blood vessels that can occur where you blow your nose, pick your nose, sneeze, or especially cough. Seasonal allergies can cause the mucous membranes in your nose and mouth to dry out, and this can facilitate small blood vessel breakage. Additionally, dental or gum disease can lead to small amounts of blood appearing in your saliva/phlegm. This is a normal occurrence; your body will heal on its own. Since this occurred first thing in the AM, I imagine that you, like most people, have some phlegm that pools throughout the night and isn't completely cleared until you cough it up. As such, you made see more blood than during the day because it has had time to accumulate. Conditions that are more concerning include pneumonia, tuberculosis, vascular (vessel) disease, and infections of the nose/mouth/sinuses. Unrelenting cough, fever, shaking chills, pain with breathing, drenching night sweats, coughing up large amounts of blood (with minimal phlegm), frequent nose bleeds are all concerning symptoms that should be evaluated by a doctor. If your current symptoms continue to frequently occur or if you have continued blood in your phlegm, I recommend that you be evaluated by a doctor as well. She/he will be able to evaluate and examine you to confirm that nothing is going on.

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