American Society of Hirudotherapy

Complete Indications List

Comprehensive catalog of documented hirudotherapy indications with evidence classification

Last Updated: March 1, 2026Reviewed by: Andrei Dokukin, MDRegulatory Status: FDA-Cleared (Tier 1)

This page catalogs all documented indications for hirudotherapy with regulatory tier classification based on the strength of published evidence and FDA clearance status. Each indication is classified using the ASH three-tier system.

Classification System

Tier A (FDA-Cleared): Supported by FDA 510(k) clearance and systematic review evidence. Tier B (Clinical Evidence): Supported by RCTs or controlled studies; not FDA-cleared. Tier C (Investigational): Documented in international clinical literature (case series, expert experience); requires investigational framing and appropriate disclaimers.

Tier A — FDA 510(k)-Cleared Indications

FDA-Cleared Indication

These are the only indications included in the FDA 510(k) clearance for medicinal leeches.

ConditionEvidenceSpecialtyTier
Venous congestion — microsurgical flap salvageOnly FDA 510(k)-cleared indicationSystematic reviews (n=277, n=407); 78% salvageSurgeryTier A
Venous congestion — digit/tissue replantationIncluded in 510(k) K040187 languageCase series; prophylactic 92% vs reactive 67%SurgeryTier A

Tier B — Clinical Evidence (Not FDA-Cleared)

Clinical Evidence — Not FDA-Evaluated

These indications are supported by controlled clinical studies but are not included in the FDA 510(k) clearance. Use requires off-label disclosure in informed consent.

ConditionEvidenceSpecialtyTier
Knee osteoarthritisLevel I: Michalsen 2003 (n=51 RCT), Andereya 2008 (n=113 sham-RCT)RheumatologyTier B
Chronic venous insufficiencyLevel III: Multiple comparative cohortsVascularTier B
Acute thrombophlebitisLevel III: n=46+87 comparativeVascularTier B
Post-thrombotic syndromeLevel III: n=87 comparative cohortVascularTier B
Wound healingLevel III: Multiple controlled studiesDermatologyTier B
Pain syndromes (localized)Level I-II: Some RCT data for OA, epicondylitisPain MedicineTier B

Tier C — Investigational / International Evidence

Investigational / Research Priority

These indications are documented in international clinical literature, primarily case series and expert clinical experience. ASH supports controlled clinical investigation of these applications.

ConditionEvidenceSpecialtyTier
Coronary artery diseaseLevel IV: Case series (n=97, n=530)CardiologyTier C
HypertensionLevel III-IV: Gantimurova 2001 (n=94+20), Baskova cohort (n=42)CardiologyTier C
Congestive heart failureLevel IV: Case series (n=65)CardiologyTier C
Cerebrovascular diseaseLevel III: Comparative cohort (n=197+)NeurologyTier C
Acute angle-closure glaucomaLevel III: n=302 comparativeOphthalmologyTier C
Chronic glaucomaLevel III: n=340 comparativeOphthalmologyTier C
Osteoarthritis (non-knee)Level IV: Case series (n=162)RheumatologyTier C
Sensorineural hearing lossLevel IV: Case series (n=104)OtolaryngologyTier C
SinusitisLevel IV: Case series (n=60)OtolaryngologyTier C
Vasomotor rhinitisLevel IV: Case series (n=55)OtolaryngologyTier C
Inflammatory eye diseaseLevel IV: >300/yr clinical experienceOphthalmologyTier C
Inflammatory gynecological conditionsLevel IV: Case seriesGynecologyTier C
Hepatobiliary diseaseLevel IV: Case seriesGastroenterologyTier C
Endocrine/metabolic conditionsLevel IV: Limited dataEndocrinologyTier C
Dental/oral surgery congestionLevel IV: Case reportsDentistryTier C
Urological inflammatory conditionsLevel IV: Case seriesUrologyTier C
Pediatric applicationsLevel IV: Limited data; relative CI age <6PediatricsTier C

Absolute Contraindications

  • Hemophilia or severe hemorrhagic diatheses
  • Severe anemia (Hb <8 g/dL)
  • Hemodynamic instability
  • Arterial insufficiency at application site
  • Cachexia
  • Documented allergy to leech SGSry gland secretion
  • Patient refusal

Relative Contraindications

  • Concurrent anticoagulant therapy
  • Alcohol intoxication
  • Active fever
  • Pregnancy
  • Immunocompromised state
  • Children under 6 years of age

High-Risk Drug Interactions

Thrombolytics: Absolute Contraindication

Concurrent use of thrombolytic agents with medicinal leech therapy is absolutely contraindicated due to extreme hemorrhagic risk. Other anticoagulants (warfarin, DOACs, heparin) represent high-risk interactions requiring close monitoring.

Related Resources

Clinical Specialties

Evidence organized by medical discipline.

Learn more →

Safety & Infection Control

Contraindications, drug interactions, and safety protocols.

Learn more →

Regulatory Framework

FDA clearance details and scope of practice.

Learn more →

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.