Pediculosis is very common in school environments and should not be considered a cause of poor hygiene: it depends on a small parasite, the louse, which lives only on the human head and feeds on his blood. The nits (eggs) which are mostly laid behind the ears and on the nape of the neck, adhere to the hair thanks to a sticky substance: the remedy recommended by Derbe is Pid Oil. Pid oil is not a shampoo: it is a real oil that washes the hair, sanitizes and creates an environment unfavorable to the settlement of unwanted guests. Its characteristic smell comes from the natural essences it contains.