American Society of Hirudotherapy

The medicinal leech: a page from the annelids of internal medicine

Historical review published in Annals of Internal Medicine (1988)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Preclinical (animal)Drug DevelopmentAdams SL · Annals of internal medicine, 1988

Abstract

Leeches have been used in health care since ancient times by physician and layman alike. As just one of several methods of bloodletting, the leech became the focus of a science that included such subjects as indications, modes of attachment, complications, and relative contraindications. The popularity of leeching has varied immensely over the years. In the 19th century, this annelid saw its numbers decimated because of protean medicinal indications. The leech lost its hold on the practice of medicine in the early 20th century. Recently, the use of leeches has resurged in both the lay and the scientific communities.

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

Publication typeHistorical ArticleJournal Article
Indexed MeSH termsAnimalsBloodlettingEuropeHistory, 18th CenturyHistory, 19th CenturyHistory, 20th CenturyHistory, AncientLeechesUnited States

Summary

Historical review of medicinal leech use covering ancient times through the 19th-century European peak (1830-1850) decline and modern resurgence in microsurgery.

Why This Matters for Hirudotherapy

This historical article surveys the medicinal leech's role in health care from antiquity through the 20th century, framing it within the broader practice of bloodletting that encompassed indications, modes of attachment, complications, and relative contraindications. It traces the dramatic fluctuation in leeching's popularity—especially the 19th-century surge in demand that decimated leech populations—and notes a recent resurgence in both lay and scientific interest. For ASH, this provides cultural and historical context for the leech's enduring place in medicine. Caveat: this is a historical/narrative article with no original scientific data, clinical findings, or secretome characterization.

Citation

The medicinal leech: a page from the annelids of internal medicine.

Adams SL · Annals of internal medicine, 1988

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.