The idea of investigating the influence of colours on itching came from a team led by dermatologist Simon Mueller at the University Hospital Basel. The background of the study: Many people start to itch when they see images of parasites on the skin or something similarly repulsive. This phenomenon is referred to as ‘contagious itch’. If itching can be triggered merely by looking at an image, could it also be relieved in the same way? The Basel team investigated this question in a two-phase study on 72 patients.
Phase 1: The patients, all of whom suffered from chronic itching, were asked if they could assign a colour to their ailment. Nearly 95 per cent of them said the itching was ‘red.’ When asked which colour alleviates itching, 80 per cent chose blue or green.
Phase 2: The patients sat in a darkened room and looked at the colours they chose on a screen for ten minutes. The itching did in fact improve (or worsen) significantly.
The research team is considering various possible applications, such as colours in hospital rooms, product colours for itch relief ointments or packaging for dermatological medicines.
Individual patients could also use VR (virtual reality) glasses to achieve the optimal colour shade and saturation that alleviates their itching.
Drechsler N. Rot verstärkt, Blau und Grün lindern den Juckreiz (Red makes itching worse, while blue and green relieve it). Press release of the University Hospital Basel, 2 June 2020. (In German)