American Society of Hirudotherapy

Piscicolin

Small direct thrombin inhibitor described in the fish leech Piscicola geometra secretome.

Preclinical / mechanisticLast updated: 2026-05-26 · Reviewed by ASH Editorial Board
Molecular weight of Piscicolin compared with other characterized leech-derived compoundsHementerin80 kDaHementin80 kDaHementin-Like Protein (HLP-1)80 kDaLeech Collagenase70 kDaHaemadipsa yanyuanensis Progr…70 kDaLeech Apyrase67 kDaCalin65 kDaHyaluronidase60 kDaAntithrombin III binding prot…58 kDaCollagenolytic Fibrinolysin55 kDaLeech Thrombospondin-Like Pro…50 kDaPiscicolin5.5 kDa
Molecular weight (kilodaltons) of Piscicolin (highlighted) alongside other characterized leech salivary compounds. Smaller proteins/peptides generally diffuse and act faster.

Mechanistic Evidence Box

Preclinical / mechanistic
Page type
Compound profile
Evidence type
Small direct thrombin inhibitor described in the fish leech Piscicola geometra secretome.
Evidence level
Mechanistic discussion
Drug vs leech
Purified natural compound
Safety domains
Bleeding

Clinical translation limit

Piscicolin is documented mechanistically only; no human evidence. Piscicola geometra is not used clinically on humans, and piscicolin has no FDA-approved derivative.

Molecular Profile

Category
Anticoagulant
Evidence tier
Preclinical
Molecular weight
5,500 Da
Source species
Piscicola geometra
Discovered
2015
Piscicolin molecular structure

Biological Targets

  • → thrombin (Factor IIa)

External Resources

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    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.