American Society of Hirudotherapy

Effectiveness of topical gel of medical leech (Hirudo medicinalis) saliva extract on patients with knee osteoarthritis: A randomized clinical trial

RCT published in Complementary Therapies in Clinical Practice (2017)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Randomized controlled trialClinical TrialsSalivary PharmacologyDrug DevelopmentShakouri A, Adljouy N, Balkani S et al. · Complementary therapies in clinical practice, 2017

Abstract

Leech saliva extract (LSE) in the liposome-based gel was used as a supplementary treatment to relief the signs and symptoms of osteoarthritis (OA). The saliva of medical leech was extracted and nano liposomes were used to formulate the supplement to enhance skin absorption. A clinical trial was designed to evaluate the therapeutic effects of LSE liposomal gel. Lenquesne and VAS questionnaires were used as indexes of this supplement therapy efficacy for 30 days. Questionnaires analysis showed that after one-month administration of LSE liposomal gel, patients' pain was relieved approximately up to 50%; also, due to reduction in joint inflammation and stiffness, the range of motion was increased and the patients' quality of life was enhanced (p < 0.001). LSE nano scaled liposomal gel as an innovative supplement therapy in OA patients, makes desirable therapeutic approach, which seems to make a significant impact on patient's quality of life and self-care capability.

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

Publication typeJournal ArticleRandomized Controlled Trial
Indexed MeSH termsAnimalsFemaleHirudo medicinalisHumansMaleMiddle AgedOsteoarthritis, KneePainPain ManagementQuality of LifeRange of Motion, ArticularSaliva

Summary

30-day RCT of a nanoliposomal leech-saliva-extract topical gel for knee osteoarthritis demonstrates approximately 50% pain reduction, decreased inflammation and stiffness, and improved range of motion and quality of life.

Why This Matters for Hirudotherapy

This clinical trial evaluated a topical liposomal gel containing medical leech saliva extract as supplementary treatment for osteoarthritis over 30 days, measuring outcomes via Lequesne and VAS questionnaires. The authors report approximately 50% pain reduction, decreased joint inflammation and stiffness, increased range of motion, and enhanced quality of life (p < 0.001). This is relevant to ASH as it explores a non-live-application formulation of the leech secretome, potentially extending hirudotherapy concepts into topical therapeutics. Caveats include that the abstract does not specify comparator groups, randomization details, or blinding, and the formulation is described as a supplement rather than a validated drug; the specific bioactive components responsible and long-term efficacy beyond one month are not established.

Citation

Effectiveness of topical gel of medical leech (Hirudo medicinalis) saliva extract on patients with knee osteoarthritis: A randomized clinical trial.

Shakouri A, Adljouy N, Balkani S et al. · Complementary therapies in clinical practice, 2017

DOI

Added to ASH library: May 26, 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.