Well, it could be a rash. Or, it could be a circulation problem. Only a physical examination by a health care provider can say for sure what's going on.
I'd advise you to get this checked out sooner rather than later. If it's a rash, your health care provider can recommend a treatment. If it's a sign of a larger problem, your healthcare provider can get a jump on treating it, which means a better outcome for you. There's simply no downside to getting a doctor to look at this.
Researchers in the Department of Dermatology at St. Vincent's Hospital in Australia first identified golfer's vasculitis in the February 2005 "Australasian Journal of Dermatology." The rash is named because it appeared on the lower legs of golfers who had been playing in high temperatures. The rash is reddish-purple in color and does not itch. It is caused by inflammation of the blood vessels and is not an allergic reaction. The researchers reported that the patients who had golfer's vasculitis were typically over 50 years old and otherwise healthy. As of July, 2011 there are no specific treatments or preventative measures recommended, but the rash should eventually go away on its own. If it does not go away after several days, consult a doctor.
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