Serrapeptase is a proteolytic enzyme that has attracted sustained scientific and clinical interest since its isolation in the 1970s. Unlike many popular supplement ingredients whose reputations rest primarily on traditional use, serrapeptase has an identifiable mechanism of action and a growing body of clinical and laboratory research. It is not a vitamin or mineral — it is an enzyme, and understanding what enzymes actually do in the body is the key to understanding why serrapeptase's properties are genuinely interesting. Here is a clear-eyed account of what it is, what the research shows, who might benefit, and what precautions apply.
What Is Serrapeptase?
Serrapeptase (also written as serratiopeptidase) is a proteolytic — protein-digesting — enzyme originally isolated from bacteria of the genus Serratia, specifically Serratia marcescens E-15, found in the gut of the Japanese silkworm (Bombyx mori). In its natural context, the enzyme helps the silkworm digest tough mulberry leaves and, crucially, dissolve the hardened silk cocoon during metamorphosis — a function that requires breaking down structural proteins without damaging surrounding living tissue.
This selectivity — the ability to digest non-living or structurally abnormal protein material while leaving healthy tissue intact — is what makes serrapeptase pharmacologically interesting. When taken orally in enteric-coated form (coating that protects the enzyme from stomach acid and allows it to be absorbed intact in the small intestine), serrapeptase enters systemic circulation bound to alpha-2-macroglobulin, a carrier protein that may help direct it to sites of inflammation and protein deposition.
Serrapeptase is measured in SPU (Serrapeptase Units) or SU — units of enzymatic activity rather than weight. Higher SPU values indicate higher enzymatic activity. Common supplemental doses range from 40,000 to 120,000 SPU per day.
How Serrapeptase Acts in the Body
As a protease, serrapeptase catalyses the hydrolysis of proteins. Its proposed mechanisms of action include:
- Reduction of viscous secretions — by breaking down the mucoprotein components of mucus, serrapeptase may help reduce the viscosity of secretions in the respiratory tract, making them easier to clear
- Anti-inflammatory effects — research has demonstrated that serrapeptase modulates acute-phase proteins involved in the inflammatory response, including effects on complement components C3 and C4 and C-reactive protein (CRP)
- Analgesic activity — by blocking the release of bradykinin and other pain-mediating amines from inflamed tissue, serrapeptase may help reduce pain associated with inflammation
- Fibrinolytic activity — serrapeptase can break down fibrin, the protein that forms blood clots and scar tissue; this underlies interest in its role in cardiovascular contexts and post-surgical recovery
- Biofilm disruption — laboratory research has found serrapeptase may enhance antibiotic penetration of bacterial biofilms, including those formed by Staphylococcus aureus
What the Evidence Shows
Serrapeptase has been studied in multiple clinical trials, particularly in European and Asian contexts. The evidence base, while not as extensive as for well-established pharmaceuticals, includes controlled trials with meaningful findings:
Post-surgical swelling and inflammation: Several controlled studies have found serrapeptase to be significantly more effective than placebo in reducing post-operative oedema and pain — most notably in oral and maxillofacial surgery. Its classification as a standard anti-oedemic agent in several European countries reflects this clinical recognition.
Respiratory conditions: Studies in conditions involving excess mucus production — including chronic sinusitis and chronic bronchitis — have shown reductions in secretion viscosity and volume in serrapeptase groups compared to placebo.
Breast engorgement: A double-blind controlled trial reported significant reduction in breast pain and swelling in patients receiving serrapeptase compared to placebo, with positive outcomes in the majority of the treatment group.
Cardiovascular interest: Preclinical and observational data have generated interest in serrapeptase's fibrinolytic properties in the context of arterial plaque and vascular health. This area remains an active subject of research rather than a clinically established application, and serrapeptase should not be considered a replacement for medical management of cardiovascular disease.
It is important to note that serrapeptase does not have approved EU health claims. The evidence base — while promising — does not yet meet EFSA's threshold for authorised claims. Long-term safety studies are also limited, which is why most practitioners recommend use limited to defined periods.
[tip:Serrapeptase must be taken in enteric-coated form on an empty stomach — at least 30 minutes before meals or 2 hours after. Enteric coating protects the enzyme from being denatured by stomach acid, allowing it to reach the small intestine intact for absorption. Taking serrapeptase with food significantly reduces its bioavailability.]Serrapeptase and Nattokinase: A Common Pairing
In the supplement market, serrapeptase is frequently combined with nattokinase — a different proteolytic enzyme extracted from natto (fermented soya beans). The two enzymes have complementary mechanisms: serrapeptase is better studied for anti-inflammatory and mucolytic applications, while nattokinase has stronger research support specifically for fibrinolytic (clot-dissolving) activity and cardiovascular applications. Combined formulas are popular among people seeking systemic enzyme support for circulation and inflammation simultaneously.
Nattokinase has its own body of clinical research, particularly for blood flow and cardiovascular parameters, and is covered in more detail in our broader cardiovascular supplement category. Both enzymes carry anticoagulant properties that require careful consideration if you take blood-thinning medications — see the contraindications section below.
Serrapeptase Supplements at Medpak
We carry serrapeptase in multiple potencies from established brands. Doctor's Best and Now Foods offer enteric-coated formulas in both standard and high-potency formats:
[products:doctors-best-serrapeptase-40-000-spu-90-capsules, doctors-best-serrapeptase-120-000-spu-90-veg-capsules, now-foods-serrapeptase-60000-spu-60-veg-capsules, haya-labs-serrapeptase-60000-spu-60-veg-capsules, haya-labs-serrapeptase-40000-spu-90-veg-capsules]Nattokinase Supplements at Medpak
For those interested in nattokinase — either alongside or instead of serrapeptase — we carry several options from trusted brands, including the clinically studied NSK-SD® form. Nattokinase is also of particular relevance for cardiovascular health support; explore our full cardiovascular supplements collection for broader context:
[products:doctors-best-nattokinase-2-000-fus-90-veg-capsules, aliness-nattokinase-nsk-sd®-100-mg-60-capsules, healthy-origins-nattokinase-2000-fus-60-capsules, haya-labs-nattokinase-2000-fu-90-capsules, invent-farm-nattokinase-300-mg-60-capsules]Who May Be Interested in Serrapeptase
Based on its researched properties, serrapeptase is most commonly used by people managing chronic inflammatory conditions, those recovering from surgery or physical injury, people with respiratory conditions involving excess mucus, and individuals with an interest in systemic enzyme support as part of a broader health maintenance approach. It appears in the supplement routines of both active adults and older individuals, and its vegan origin — derived from bacterial culture rather than animal sources — makes it compatible with plant-based diets. For complementary digestive enzyme and gut health support, our digestive system collection provides additional options.
