Louse egg

Louse eggs, commonly known as nits, are the embryonic life stage of the head louse, Pediculus humanus capitis, and serve as a critical focal point in the treatment of pediculosis [1][2]. These eggs are encased in a protective chitinous shell and are cemented to hair shafts close to the host's scalp, where warmth facilitates incubation [1][3]. From a pharmacological perspective, louse eggs are targeted by pediculicides that possess ovicidal properties, which are essential for preventing the hatching of new nymphs and ensuring complete eradication of the infestation [2][4]. Ovicidal agents work through various mechanisms, including neurotoxic disruption of the developing embryo's nervous system or physical occlusion of the egg's respiratory structures, leading to asphyxiation [4][5]. Newer therapeutic approaches, such as metalloproteinase inhibitors, specifically target the biochemical processes necessary for egg hatching [6]. Because many standard treatments have limited efficacy against the egg stage, the presence of viable nits often necessitates repeat applications or the use of specialized formulations to achieve clinical success [1][5].

Other names

NitPediculus humanus capitis eggHead louse egg

Pediculicides target louse eggs through chemical neurotoxicity (e.g., malathion, spinosad), inhibition of metalloproteinases required for hatching (e.g., abametapir), or physical mechanisms such as suffocation and dehydration by coating the egg and blocking gas exchange (e.g., dimeticone) [2][4][6].