A consultation with a dermatologist should be considered. Diagnosing scalp conditions is sometimes difficult, even for a specialist. The two most common conditions that fit this description are psoriasis and seborrhoeic dermatitis. In both cases, targeted application of care products containing urea and/or salicylic acid will improve symptoms. They tend to come and go, with chronic and recurrent flare-ups: it’s important to seek the advice of a dermatologist.