Extreme itching on the groins or the genitalia with scaling often could be because of psoriasis. In psoriasis there is a lot of these are actually because none or it can be severe, depending on the intensity of psoriasis. However dandruff like reaction can present with scaling, itching. Many at times these conditions are no constant but they fluctuate. So you need to consult a dermatologist wen the lesions are full blow. Do not apply any creams in that area because that alters the morphology. Arriving at a diagnosis might be difficult. Rarely applications of some creams or deo or some other things can give rise to irritant reactions where people can again present with itching and scaling. So itching and scaling has to be checked for these conditions and have to be treated for it appropriately.
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