Pediculosis is a skin infestation due to blood-feeding ectoparasitic insects. It is more commonly caused by Pediculus humanus var. capitis (head lice), which affects the scalp, or by Pthirus pubis (pubic lice), usually detected in hair bearing genital and axillary areas in adults or, less frequently, on the eyelashes in children. The diagnosis in both cases is generally clinical. Dermatoscopy allows a clear, definitive visualization of parasites and nits fixed to the hair shaft and a more detailed differentiation of full versus empty nits, providing useful information about therapeutic response. Pseudonits (hair casts, debris of hair spray or gel, or scales) can be unequivocally identified with this technique.