Hello,
Welcome to XXXXXXX

According to your description only your lower lip suddenly turned black.
-     Can you clarify whether it became red first and then black or by red you are describing your natural lip color?
-     Was it itchy or burning in the initial stage of discolouration?
-     Did you take any new medicines before this discolouration happened?
-     Did you apply anything new on the lip?
-     Did you expose yourself excessively to sunlight?
-     Do you smoke?

There is an option on the right side of your query page to upload your photo. Please make use of it so that I can better answer your query.

I am thinking of a lot of conditions like Fixed drug eruption, sunburn, contact dermatitis etc.
The details asked especially the photo will be very helpful.

Waiting to hear from you,
Regards
Dr Johny Chacko.
Take care.

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Hello,
Welcome back.
Saw the picture that you sent. In the picture I can see blackish color of the lower lip, but what interests me is a scaly / dry well defined area over the lip which is slightly violaceous. I want to know whether lip is actually scaly or is it just an artifact because of the flash.

If it is scaly and slightly violaceous I am thinking of two conditions.
One is mucosal lichen planus, the second one is a collagen vascular disease called DLE or dermatology consultation as the treatment for these conditions should be by a specialist and it requires long term follow up. A skin biopsy from the lip will help to confirm the disease.

I will be happy to clarify any further doubts you have.
Wish you good health.

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