American Society of Hirudotherapy

Icaridin-Loading Nitrocellulose As a New Repellent Against Aquatic Leech with Waterproof and Long-Acting Properties

Basic science / preclinical published in Vector borne and zoonotic diseases (Larchmont, N.Y.) (2022)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Safety & Infection ControlZeng W et al. · Vector borne and zoonotic diseases (Larchmont, N.Y.), 2022

Abstract

Leech attachment is a common nuisance to outdoor recreationists and farmers in aquatic environments. Consequences include bleeding, infection, and, rarely, death. Methods to prevent leech attachment are anecdotal and individual; effective repellent formulations with universal applicability are needed. In this study, icaridin is demonstrated to be repellent and toxic to aquatic leech, and formulation of icaridin loading nitrocellulose (Icar-Nitr) is proposed as a new leech repellent. The nitrocellulose provided sustained drug release and waterproof properties. One optimal formulation, 10-Icar-Nitr, proved effective for leech repelling in aquatic environment. Using a rat model, the same formulation also showed removal and killing after leech attachment. The nitrocellulose reduced percutaneous absorption of icaridin, and 10-Icar-Nitr showed good biocompatibility. This study provides a potential new and practicable strategy for prevention and removal against leech attachment and bites.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal Article
Indexed MeSH termsAnimalsBites and StingsCollodionInsect RepellentsPiperidinesRats

Summary

Leech attachment is a common nuisance to outdoor recreationists and farmers in aquatic environments. Consequences include bleeding, infection, and, rarely, death.

Why This Matters for Hirudotherapy

This study examined an icaridin-loaded nitrocellulose formulation (Icar-Nitr) designed to repel, remove, and kill aquatic leeches, evaluating its sustained-release, waterproof, and biocompatibility properties using a rat model. For ASH's domain, the connection is limited and inverse: the work concerns preventing and eliminating nuisance leech attachment rather than any therapeutic application of leeches or their salivary secretome. While it touches on leech–host skin interactions, it does not involve medicinal leech therapy, and the aquatic leech context and prophylactic aim differ substantially from controlled hirudotherapy. The findings are preclinical, based on an animal model, and oriented toward anti-leech repellency, making their direct relevance to therapeutic leeching essentially negligible.

Citation

Icaridin-Loading Nitrocellulose As a New Repellent Against Aquatic Leech with Waterproof and Long-Acting Properties.

Zeng W et al. · Vector borne and zoonotic diseases (Larchmont, N.Y.), 2022

DOI

Added to ASH library: March 18, 2026 · Site last updated: June 18, 2026

This website provides educational information and does not constitute medical advice, diagnosis, or treatment recommendations. Medicinal leech therapy carries clinically meaningful risks and should be performed only by qualified clinicians under institutionally approved protocols. FDA 510(k) clearance for medicinal leeches is limited to specific indications; investigational and off-label discussions are labeled accordingly. For patient-specific guidance, consult a qualified healthcare provider.