Discoloured patches on the skin can actually mean either it is a dark patch or it can be a white patch. Any of these things can be considered a discoloured. Whenever the colour is not normal, then rather an increase in the colour or a decrease in the colour is called as a discoloured patch. So commonly whenever it comes to a discoloured patch, people fear about the white patches. White patches are an allergic like reaction of the skin which gives you damage to the melanocytes which gives melanin and thereby gives you less of melanin. Once the melanin is less in the skin, it gives you a whitish in colour. So this is what is called as vitiligo. Vitiligo can be because of various reasons like allergies, sometimes acutely it can be induced by stress. It can be also be because of contact dermatitis where we are exposed to some chemicals or some metals, for example some artificial jewellery, if you can develop the white patches. Also sometimes rubber can also cause some irritation reaction and can give you depigmentation, for example rubber foot wear, it can give rise to white patches in the foot. So these are some common causes for white patches in the skin. Apart from that even sever sun allergy can give rise to white patches of the face, on the extensor aspects of the arms or the outer aspects of the arms and also on the ear lobes. White patches can happen also because of hot and humid climate, where there is lot of fungal infection, like for example pityriasis versicolor, that we refer to as a superficial fungal infection. This many at times may not give you itching, pain or any discomfort, where the skin looks whitish in colour. Part form these darker skin also, the patches of dark discoloration can also give rise to a discoloured skin and his can happen because of hormones. For example in melasma, people develop a lot of brown patches in the checks. So that again looks discoloured or it can be because of picking of the pimples. Sometime pimples are meddled and can give rise to a lot of skin pigmentation or it can be even because of fungal infection which has healed with a dark patch or it can be because of other various allergy like reaction, what we call it as pityriasis versicolor, pityriasis rosea or it can be because of lichen planus to even psoriasis when it heals, it gives rise to dark patches and most important thing is whenever these pigmentations are there, it is always important to check for the root cause and treat it. The treatment varies depending upon the etiology or the cause of the condition.
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