American Society of Hirudotherapy

Clinical Efficacy of Leech Therapy (Ta'liq al-'Alaq) in Eczema (Nar Farsi): An Open-Label Single-Arm Clinical Study

Ulla P BS, Aaisha B, Bokhari S, Zabiulla P, Alam MA, Nikhat S (2025) · Alternative Therapies in Health and Medicine · n=20

RCT evidence detailTrial reference
GRADE Very LowInsufficient evidenceCondition: Knee Osteoarthritis
Sample size of this trial compared with other Knee Osteoarthritis trialsWang H 2018264Lauche R 2025240Lauche R 2014237Farzali S 2025181Cui Y 2024144Andereya S 2008113Andereya S 2008113Sarbaev IS 201996Isik M 201790Ulla P BS 202520
This trial (highlighted) by sample size alongside other indexed Knee Osteoarthritis trials. Larger trials generally carry more statistical weight.

Study Profile

Design
single-center, open-label, single-arm clinical study of leech therapy for eczema in the Unani medicine tradition (India)
Sample size (n)
20
Intervention
Four sessions of leech therapy with one-week intervals; standardized Ta'liq al-'Alaq (leech therapy) protocol per Unani medicine practice
Comparator
Within-subject pre/post comparison using standardized Eczema Area and Severity Index (EASI) - no randomized control arm
Primary endpoint
Eczema Area and Severity Index (EASI) score - components for redness, edema, excoriation, lichenification, and total area
Primary result
Statistically significant improvement in eczema severity: redness (p=0.0001), edema (p=0.0001), excoriation (p=0.0022), lichenification (p=0.0001); total area involved did not show statistically significant decrease (p=0.24); all 20 patients completed the trial with no dropouts
Follow-up duration
4 weekly sessions (~28 days)

Key Findings

  • First PubMed-indexed Unani medicine clinical trial of leech therapy for eczema (Nar Farsi)
  • Significant within-subject improvements in three of four EASI components (redness, edema, excoriation, lichenification)
  • Total skin area involvement did not significantly decrease - suggests symptomatic improvement without disease-modifying area reduction
  • 100% completion rate (no dropouts) signals patient acceptability of multi-session leech protocol
  • Provides hypothesis-generating signal for leech therapy in inflammatory dermatologic conditions

Limitations

  • Single-arm design with no randomized control - entire effect could reflect natural fluctuation, placebo, or attention
  • Small sample (n=20)
  • Open-label evaluation by treating clinicians who knew the intervention
  • Single Unani medicine institution - selection bias toward CAM-favorable patient population
  • Eczema is a relapsing-remitting condition - 4-week follow-up cannot assess durability

Clinical Implications

Ulla 2025 is the only PubMed-indexed Unani-medicine clinical study of leech therapy for eczema and provides exploratory evidence that leech application may improve inflammatory eczema parameters. The single-arm uncontrolled design limits causal inference, and the lack of total-area improvement suggests symptomatic-only effect. For ASH editorial purposes, this study is cited only as preliminary cross-cultural evidence; it does not support routine use in eczema. The trial illustrates the broader Unani medicine application of leech therapy across dermatologic indications - a use case largely absent from the Western evidence base.

Related Trials

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.