White spots on lips can one be because of mechanical trauma. Lot of people have the habit of picking the lips and peeling off a little bit of dead skin that is accumulated on the lips. What happens in this process is there is recurrent injury to the lips and then because of that there is a white patch. Commonly this type of damage happens on the centre portion of the lips where they tend to peel it off like this and when it happens they cause damage to the skin recurrently and you are not allowing the skin to heal and during these times there can be some amount of discolouration of the lips, and commonly it gives you a white patch and in addition to that, second thing is a contact dermatitis. Sometimes smokers, it is well known that whenever people smoke, their lips tend to be dark, but occasionally it can also give rise to a central white patch. So if you have a habit of smoking and you see a white patch, better you quit smoking. Third thing is whenever there is a condition called as vitiligo, means it is an autoimmune condition, an allergy like reaction where there is some damage to the colour producing cell, that is melanocyte and because of that, the area that is supplied by that cell goes white and that is what is called as vitiligo or what people call it commonly as leucoderma. These are some causes for white lips In addition to that rarely we get conditions like discoid lupus erythematosus where there is an allergy like reaction of the skin in the centre and people develop a white patch in the centre, with periphery with a little bit of a violaceous stain and this can also look similar to a vitiligo patch. These are some common causes for whitening of the lips.
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