Fibrinase

EnzymeBest taken away from food

What is it

Fibrinase is a generic term that can refer to enzymes that act on fibrin (blood clot protein). Supplements may include fibrinolytic enzymes such as nattokinase or serrapeptase, sometimes labeled as soy bean fibrinase when sourced from fermented soy.

Evidence for 1 use

AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.

Cardiovascular markers (nattokinase as primary evidence)

Limited Evidence

Small RCTs of nattokinase suggest modest blood pressure reduction and fibrinolytic effects. Direct evidence for generic 'fibrinase' supplements depends on the specific enzyme used.

How it works

Fibrinolytic enzymes are proposed to help break down fibrin in blood clots and inflammatory exudates. Nattokinase, the best-studied example, is derived from natto (fermented soybean) and has been studied for cardiovascular and circulatory effects. Clinical evidence is mixed; nattokinase has shown some lowering of blood pressure and modest fibrinolytic activity. Serrapeptase has been used in Japan and Europe for inflammation and post-surgical edema, though with mixed quality of evidence.

Dosage

Nattokinase: typically 2,000-4,000 FU per day. Serrapeptase: 10-60 mg per day. Other 'fibrinase' supplements vary.

When and how to take it

Often taken on an empty stomach (30 minutes before or 2 hours after meals) to maximize enzyme activity. Follow product label.

2 commercial forms

Compare the main delivery options and what they’re best suited for.

Nattokinase

Best-studied fibrinolytic supplement.

Enteric-coated to survive stomach acid

Serrapeptase

Used in some inflammation products.

Enteric-coated for intestinal release

Safety

Generally well-tolerated. Theoretically, fibrinolytic enzymes can increase bleeding risk, although clinical reports are rare. Stop before surgery and discuss with clinicians if you take blood thinners.

Who should be cautious

Avoid before surgery and in active bleeding conditions. Avoid in pregnancy and breastfeeding due to lack of data. People on anticoagulants should consult their clinician.

Interactions

Possible additive effects with anticoagulants and antiplatelet drugs (aspirin, warfarin, DOACs). Use caution with NSAIDs.

Food sources

Natto (fermented soybean)

Amount
1 oz
%DV
—

Frequently asked questions

Is fibrinase the same as nattokinase?⌄

Nattokinase is the most studied fibrinolytic enzyme supplement, derived from natto. 'Soy bean fibrinase' may refer to nattokinase or a related enzyme.

Can I take fibrinase with aspirin?⌄

Combining fibrinolytic enzymes with antiplatelet drugs may increase bleeding risk. Discuss with your clinician.

References

Fibrinase on Wikidata — Wikidata link

Fibrinase on NIH DSLD (US supplement label database) — NIH Dietary Supplement Label Database link

Research on Fibrinase (PubMed search) — PubMed link

Track Fibrinase with Pilora

Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.

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Evidence-based·How we grade evidence

Disclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you’re pregnant, breastfeeding, on medications, or managing a chronic condition.