ZocdocAnswersWhat are these red spots on my legs that are warm to the touch but do not itch?

Question

What are these red spots on my legs that are warm to the touch but do not itch?

I took Benadryl thinking it was an allergic reaction but it did not go away. The largest is about an inch wide.

Answer

Thank you for this interesting question. In order to determine the cause, I would need more information. I would need to know the full details of your medical history and also perform a thorough physical exam, including a skin exam. Depending on these results, you may need additional testing, such as a biopsy of the affected area. Only after collecting this information would it be possible to provide a possible diagnosis. Therefore, I strongly encourage you to schedule an appointment with a dermatologist. There are many potential causes for these spots. It is possible this represents erythema nodosum, which is a buildup of fat cells beneath the skin. Often, the cause of this is idiopathic, meaning no clear cause is identified. It can also be caused by bacterial, viral, or fungal infection as well as cancer, autoimmune disorders, or a drug reaction. These could be purpuric lesions, which can be caused by hematologic disorders. Another potential cause is pyoderma gangrenosum, which can be caused by cancer or an autoimmune disorders. Many other drug reactions and allergic reactions can also cause similar findings. Unfortunately, it will not be able to provide a diagnosis without seeing these lesions, and I recommend you see a dermatologist.

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

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