Wella SP Clear Scalp Shampeeling. Experience long term freedom from dandruff with Wella SP Clear Scalp Shampeeling, a regulating intensive anti-dandruff treatment. It sustainably fights stubborn dandruff for up to two months, after regular treatments over a four week period. An essential component of the SP Clear Scalp line, Wella SP Clear Scalp Shampeeling is formulated with the Dermacalm Complex which effectively yet gently clears the hair and scalp of even the most stubborn dandruff while fighting the formation of new dandruff.