The acupuncturist says, "...try this: instead of scratching the itch slap it". The relief afforded by the slap is not quite the same. To scratch makes a sort of crescendo of sensation that is orgasmic in a tumescent kind of way. Slapping, on the other hand, works in the way of a plateau - one could go on forever - for the slap excites the cells more slowly and with no damaging tears to the skin.