Pediculus humanus capitis (Head louse)

The head louse (Pediculus humanus capitis) is an obligate ectoparasite that specifically infests the human scalp and hair, where it feeds on host blood multiple times daily [1, 2]. It is the primary cause of pediculosis capitis, a highly prevalent condition characterized by scalp pruritus and secondary skin infections, primarily affecting children [2, 3]. While the head louse is not a vector for systemic bacterial diseases like the body louse, its presence causes significant social distress and physical discomfort [1, 4]. Pharmacological management involves the use of pediculicides that target various physiological processes within the louse, most notably the nervous system [5]. Common molecular targets include voltage-gated sodium channels (targeted by permethrin), acetylcholinesterase (targeted by malathion), and glutamate-gated chloride channels (targeted by ivermectin) [5, 6]. The emergence of widespread resistance to traditional neurotoxic agents has necessitated the development of newer treatments, including physical suffocants and metalloproteinase inhibitors [6, 7].

Other names

Head licePediculus capitisHuman head louse

Pediculicides target the louse through several mechanisms: disruption of voltage-gated sodium channels (Permethrin, Pyrethrins), inhibition of acetylcholinesterase (Malathion), activation of glutamate-gated chloride channels (Ivermectin), overexcitation of nicotinic acetylcholine receptors (Spinosad), and inhibition of metalloproteinases (Abametapir) [5, 6, 7].