How Do You Tell the Difference Between a Blood Blister and a Melanoma?

By Staff WriterLast Updated Mar 30, 2020 2:03:55 PM ET

Despite a superficial resemblance to blood blisters, nodular melanomas continue to grow after two to three weeks, warns the Melanoma Education Foundation. Melanomas occur in locations without injury, while blood blisters are usually the result of damaged blood vessels or skin tissue.