Treatment for Diffuse Pruritus with Eosinophilia

Introduction to Treatment

The American College of Physicians recommends that treatment for diffuse pruritus with eosinophilia should first focus on identifying and treating the underlying cause, with empirical therapy of albendazole 400 mg plus ivermectin 200 μg/kg as first-line treatment for possible helminth infection in patients with travel history to endemic regions 1

The Infectious Diseases Society of America suggests that travel history is essential to guide testing for parasitic infections 1
A complete blood count is necessary to confirm and quantify eosinophilia, as recommended by the American Society of Hematology 1
Stool studies, including concentrated stool microscopy and PCR for parasites, are crucial in diagnosing parasitic infections, according to the Centers for Disease Control and Prevention 7, 1

For parasitic infections, the World Health Organization recommends empiric treatment with albendazole 400 mg single dose plus ivermectin 200 μg/kg single dose for patients with travel history to endemic regions and negative initial workup 1
The National Institute of Allergy and Infectious Diseases suggests specific parasitic treatments, such as praziquantel 40 mg/kg as a single dose for schistosomiasis, and ivermectin 200 μg/kg daily for 1-2 days for strongyloidiasis 8, 1
For hematologic causes, the American Society of Hematology recommends cytoreductive therapy, aspirin, or interferon-α for polycythemia vera-associated pruritus, and cimetidine, carbamazepine, gabapentin, or mirtazapine for lymphoma-associated pruritus 6, 5
The Society for Immunotherapy of Cancer suggests that for immune checkpoint inhibitor-related pruritus, grade 1 (mild) cases can continue immunotherapy with topical emollients and mild-moderate potency corticosteroids, while grade 2 (moderate) cases may require holding immunotherapy and using oral antihistamines and medium-high potency topical corticosteroids 3, 4

The American Academy of Dermatology recommends topical treatments, including emollients and topical anti-itch remedies, for generalized pruritus of unknown origin 5
Systemic treatments, such as oral antihistamines, gabapentin, pregabalin, or mirtazapine, may be necessary for severe cases, as suggested by the European Academy of Dermatology and Venereology 5, 6
The British Association of Dermatologists recommends UVB phototherapy as an effective treatment for many forms of pruritus 5