Livedo reticularis is thought to be due to spasms of the blood vessels or a problem of the blood flow near the skin surface. It makes the skin look mottled in sort of a net pattern with clear borders. The condition most often shows up on the legs.

Sometimes livedo reticularis is simply the result of being chilled. And it may occur as a side effect of certain medications. A rarer, related condition called livedo racemosa may be caused by a serious underlying condition.

When to see a doctor

The condition usually clears up without treatment. See your health care provider if:

• The discolored, mottled skin doesn't go away with warming
• You have discolored, mottled skin along with other symptoms that concern you
• Painful lumps develop in the affected skin
• Sores develop in the affected skin
• You also have a condition that affects the blood flow in your limbs
• Your skin symptoms are new and you have a connective tissue disease