Pediculus humanus capitis (head lice) are obligate ectoparasites that live on the human scalp. While common, head lice infestations usually present with scalp itchiness and are rarely associated with hematologic abnormalities. A 30-year-old woman presented with a generalized itchy rash persisting for three months. Her medical history was unremarkable. Examination revealed erythematous papules and plaques on the trunk and upper limbs, along with yellowish crusted patches on the upper back and neck suggestive of impetigo. Scalp examination uncovered a heavy infestation of nits, adult lice, and nymphs. Laboratory findings showed a hemoglobin level of 15.2 g/dl, a white blood cell count of 12,490 /μL, and significant eosinophilia with an absolute eosinophil count of 1,873 /μL. The patient was treated with dimethicone solution, manual nit removal, fexofenadine, amoxicillin/clavulanate, and emollients. Follow-up after four weeks showed complete resolution of the rash and elimination of head lice. This case highlights the unusual presentation of eosinophilia associated with head lice infestation. Pediculid reactions, secondary to Pediculosis capitis, can present as generalized eczematous rashes. It is crucial to consider head lice in differential diagnoses, especially when unexplained hematologic changes such as eosinophilia are present. Further research is needed to explore the relationship between eosinophilia and Pediculosis capitis.