In 1660, a German physician first described an itch as an unpleasant sensation that inevitably prompts the desire to scratch. Itching and scratching were believed inseparable from one another. Together they constitute a cycle whereby the former is the cause and the latter is the effect. This cycle can become viscous whereby scratching creates an inflammatory response, which induces more itching. Identifying the cause of an itch becomes paramount as the cycle must be broken and prevented if possible.