American Society of Hirudotherapy

Leech therapy: when once is not enough

Research article published in Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis (1991)

Last Updated: March 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Clinical TrialsWest B, Nichter L, Halpern D · Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis, 1991

Abstract

Venous congestion is a constant threat in the survival of free flaps, pedicled flaps, tissue replantations and traumatized tissue. Leech therapy has proved effective in salvaging much of these compromised tissues. To be effective, leeches must be both readily available and hungry, requirements not always easily met. Our investigation seeks to establish a means to return sated leeches to their previous unfed, hungry state for reuse. Sated leeches were purged of their blood meals by placement in 3% hypertonic saline or by gentle finger pressure, then exposed to serotonin 0 microM (control), 10 microM, 30 microM or 90 microM for 20 min. Subsequent rebiting/refeeding was observed and analysed. Leeches bathed in serotonin rebit or reattached at nearly four times the rate of unexposed leeches; 30% vs 8% respectively. Biting, however, is not refeeding. Overall, 41 leeches were treated with serotonin with four (10%) refeeding. Those that refed consumed a significantly smaller blood meal than the initial feeding; 50% +/- 47% SD vs 348% +/- 143% SD of original body weight. None of the control group refed. As a method for routinely reusing leeches, serotonin bathing cannot be recommended. In the immediate postoperative period with the sudden emergence of venous congestion requiring leech therapy, but with an inadequate number available, this 20% [corrected] refeed rate after 10 microM serotonin exposure could potentially determine the success or failure of the flap/replantation until fresh leeches are made available.

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

Publication typeComparative StudyJournal ArticleReview
Indexed MeSH termsAnimalsChild, PreschoolFeeding BehaviorHumansInfectionsLeechesRatsRats, Inbred StrainsReplantationSerotoninSolutionsThumb

Summary

Venous congestion is a constant threat in the survival of free flaps, pedicled flaps, tissue replantations and traumatized tissue. Leech therapy has proved effective in salvaging much of these compromised tissues.

Why This Matters for Hirudotherapy

Contributes clinical evidence for the therapeutic application of leech therapy.

Citation

Leech therapy: when once is not enough.

West B, Nichter L, Halpern D · Blood coagulation & fibrinolysis : an international journal in haemostasis and thrombosis, 1991

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

Leech therapy: when once is not enough | ASH