Lichen planus is a common fungal skin infection that occurs in young and middle-aged men. It is a common fungal infection of the skin that occurs in young and middle-aged men. It is usually asymptomatic and manifests itself as hyperpigmented or (and) hypopigmented patches of skin, which may fuse with each other in an irregular pattern, commonly on the face and neck, forehead, back of the shoulders, upper arms, armpits and other sebaceous areas. The main manifestation of erythema annulare is a pale red papule at first, which can gradually expand to form a ring, with narrow, non-bulging edges and a bright red or pale red colour, with a normal skin tone in the centre of the lesion.