What causes vein in bicep to ball up to a size of large bean?
Patient: My right Bicep vein seems to ball up to the size of a large lima bean at the location of the bicep vein where it meets and disappears under the shoulder muscle. No pain. No redness or swelling of the arm. No unusual sensations at all.  Seems to have become bigger over the last 2 months and only occurs when working out (lifting weights/ cardio). When i am at rest it is not visible. Afraid its a clog or clot or maybe the blood is pooling up here and could burst the vein? Doctor: Hello,  The vein at Biceps is known as cephalic vein.This is one of major draining vessel from upper limb.During exercises output from limb increases,this is reason why this vein swelled up during exercise.It is a normal phenomenon.  Veins do not burst during exercises instead they open other channels in hard workers.So please do not bother about that.  Hope I have answered your query. Let me know if I can assist you further.  Take care  Regards, Dr. Mukesh Tiwari