ZocdocAnswersCan sun exposure cause red spots to form on the legs below the knees?

Question

Can sun exposure cause red spots to form on the legs below the knees?

I've been having red spots crop up on my legs below the knees, and I'm wondering if it could be due to sun exposure. Is this possible? I only recenly put the pieces together when I noticed that the rash always seemed to rise up after a lot of time outside in the sun.

Answer

Sun reactions on the skin are a very common reason for seeking medical advice. The doctors who will be well qualified to discuss this issue with you include your primary care doctor and your dermatologist. Sun allergy, or sensitive skin reactions to the sun, usually manifest as red, itchy, and flaking skin. Crucially, this occurs on sun exposed areas. So if you are not sun bathing your legs, of if this does not occurs on other areas exposed to sun, then it is unlikely to be a sun reaction. Sometimes, heavy sweating and overheating can cause 'heat rash' to form on affected areas of skin. These areas of skin do not have to be areas directly exposed to sun, so could involve the legs. The treatment is generally just to cool down the skin and apply a moisturizing cream. There can be rarely general medical conditions that cause spots on the lower legs. In particular if the red areas are firm and tender, this could be erythema nodosum which can signal an underlying problem and should be investigated. As always the diagnosis and the management of your particular condition will require a physical examination by your personal physician. Setting up an office visit with your primary care doctor or dermatologist might be advised.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

If you think you may have a medical emergency, call your doctor or (in the United States) 911 immediately. Always seek the advice of your doctor before starting or changing treatment. Medical professionals who provide responses to health-related questions are intended third party beneficiaries with certain rights under Zocdoc’s Terms of Service.