Brief Answer:
Needs to be looked at by a dermatologist.

Detailed Answer:
Hello Mr. XXXXXXX

Thanks for posting your query.

I'm Dr. Yogesh answering your query.

From the limited information provided by you in the query, I presume that you been having this red rash on the left leg since some time, what I would like to know is, since how long has this rash been present, and does it itch or pain.

Are there any other symptoms along with this rash, is it getting any bigger, how do the margins of the rash look, is it well demarcated and are the margins and the rash itself a bit elevated than the surrounding skin. Is there any discharge from this rash. Are you allergic to anything? How many distinct rashes can you see? Is it just one big rash or are there multiple rashes elsewhere as well?

A clinical exam would give a better idea as to what this rash might be.

Please do write back with the requested information so that I can assist you further, and if possible take a photo of the rash in normal lighting with clear focus and attach the photograph with the query so that I can see it.

There are many reason for persisting red rashes on the skin, most common of these are insect bites and allergic rashes, but they would clear out within a week's time.

Persistent rashes need to be looked at by a dermatologist to confirm the diagnosis.

I hope this will help you.

Awaiting your response.

Kind regards.

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