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"What does black blood mean?"

ZocdocAnswersWhat does black blood mean?


I have an ugly mole on my arm that I sometimes pick at (I know it's a bad habit, can't help it) and recently when I scraped it raw, it bled. The freaky thing was that the blood was almost black. What does this mean? Is blcak blood a sign of some kind of infecetion or blood poisoning?


I do agree that you should not pick and your mole. I think that if you feel it is an annoying thing, that you have it removed by a qualified physician such as a dermatologist. The color of blood is related to the amount of oxygen bound to the red blood cells. The more oxygen in the blood, the brighter red it appears. As oxygenation of the blood gets lower the blood gets darker and darker. Blood that you normally see after a cut is venous blood which has the lowest oxygen levels in the blood vessels. Occasionally in certain light, or if the oxygen level is very low, the blood can appear almost black. Blood infections are very serious but cause more noticeable symptoms such as fever and loss of consciousness. There are certain blood poisons that can cause blood to become a rust color, but usually not black. I suggest that you schedule an appointment with your primary care physician. He or she can take a look at the mole and decide if it should be removed. You can also discuss your bleeding and see if there is any additional information you should know that is specific to you personal past medical history. Good luck.

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