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"Why does my vein look dark?"

ZocdocAnswersWhy does my vein look dark?


There is a large vein in my bicep on the left hand side that has always been kinda big, but now it looks dark too. What makes a vein turn a dark color? Is it serious?


It is most likely normal to have those large veins. There are numerous large veins that run pretty close to the surface of the skin, and they are also more prominent in males and also in those with low body fat or who are physically fit. The blood that runs through veins is dark in color, which is what gives veins their blue color. In most cases, the two most common reasons why people notice that their veins seem larger or more blue in color is either that they are working out more (causing enlargement of the veins) or that, as we age, our skin tends to become gradually thinner and more translucent allowing veins to appear larger and more blue. Nevertheless, there are a few medical conditions that could cause this symptom, including a blood clot in the vein, an inflammation of the vein (known as phlebitis), or a varicose vein. For this reason, you should go see your primary care doctor, who will be able to examine the vein in question and make sure that there is no serious problem that needs further treatment. Make an appointment to see your primary care doctor at your earliest convenience!

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