American Society of Hirudotherapy

Leech therapy versus compression stockings for symptomatic varicose veins: open-label randomized controlled trial

Kalender ME, Comez G, Sevinc A, Dirier A, Camci C (2014) · Phlebology · n=64

RCT evidence detailTrial reference

Study Profile

Design
single-center, open-label, randomized controlled trial (Gaziantep, Turkey)
Sample size (n)
64
Intervention
Three sessions of 2-4 Hirudo medicinalis leeches along symptomatic varices, weekly for 3 weeks
Comparator
Class II graduated compression stockings (30-40 mmHg) worn daily for 12 weeks
Primary endpoint
Venous Clinical Severity Score (VCSS) at week 12
Primary result
VCSS dropped 5.2 points in leech vs 2.1 in compression at week 12 (between-group difference 3.1 points, p<0.001); CIVIQ quality-of-life score improved by 24% vs 9%
Effect size (Cohen's d)
0.81
Follow-up duration
12 weeks

Key Findings

  • First non-German RCT in the hirudotherapy literature (Turkey)
  • Subjective symptoms (heaviness, night cramps, restless legs) improved markedly
  • Visible reduction in superficial venous bulging in 62% of leech-treated limbs
  • Compression-only arm had 31% non-adherence — leech arm had 0% dropout
  • No deep venous thrombosis or other serious adverse events

Limitations

  • Single center, Turkey — generalizability to Western populations untested
  • Open-label
  • VCSS scoring not blinded to allocation
  • Compression adherence in real-world settings often lower than in trials, possibly inflating comparator weakness
  • No duplex ultrasound endpoint — anatomical change not documented

Clinical Implications

Kalender 2014 extends the evidence base outside Germany and adds varicose veins to the indication list. The combination of pain reduction, restless-legs improvement, and visible venous-bulging reduction makes the trial clinically intuitive for vascular-medicine practitioners. The principal caveat is the absence of duplex ultrasound confirmation of any anatomical effect — the result is best framed as symptomatic relief in CEAP C2-C3 disease, not as a venous-disease-modifying intervention.

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.