Benefits
Sinusitis and Upper Respiratory Inflammation
The only trial cited here is a 1990 multicentre, double-blind, placebo-controlled study in people being treated for acute or chronic inflammation of the ear, nose and throat, where symptoms such as pain, secretion, blockage and swelling improved more with the enzyme than with placebo. That study is now 35 years old, was run in patients under medical care rather than healthy people, and has not been repeated in a modern large trial. Thinning mucus and breaking down inflammatory proteins is the proposed explanation, and it comes from laboratory work, not from anything measured in those patients.
Post-Surgical Edema and Pain
The evidence cited here is one randomized controlled trial from 2021 in adults having impacted wisdom teeth surgically removed, where the enzyme group had less swelling and pain after the operation. No orthopedic surgery trial is cited on this page. Recovering from oral surgery under dental care is a specific medical situation and does not tell you what the supplement does for everyday aches or puffiness in a healthy person.
Fibrocystic Breast Disease
This claim traces back to an older study in women with a diagnosed breast condition, but that study is not among the references on this page. It reaches the page second hand, through a 2017 review, and it has not been replicated. Breast pain or lumps are a reason to see a doctor for a proper diagnosis, not something to self-treat with a supplement.
Carpal Tunnel Symptoms (No Trial Cited Here)
A small study is sometimes quoted for this, but no such trial appears in this page's reference list, so treat it as unverified rather than as weak-but-real evidence. Carpal tunnel syndrome is a medical diagnosis, and it is managed with wrist splinting, medication, steroid injections or surgery. Serrapeptase is not a substitute for that care.
Arterial Plaque (Untested Marketing Theory)
The idea that serrapeptase dissolves arterial plaque is a marketing story built on what the enzyme does to proteins in a test tube. There is no study in people showing it changes plaque, heart attacks, strokes or any other heart outcome. Treat it as an untested theory, not as a reason to take the product for your heart.
Mechanism of action
Protein-Breaking Activity (Laboratory Finding)
In laboratory testing the enzyme breaks down proteins involved in inflammation and clotting, such as fibrin and bradykinin. The often repeated claim that it attacks only damaged tissue and leaves healthy tissue untouched comes from that lab work and from product marketing, not from anything measured in people taking capsules.
Bradykinin Reduction
Bradykinin is a major inflammatory mediator causing pain, edema, vasodilation. In the laboratory serrapeptase breaks bradykinin down, and that is the proposed explanation for the reduced swelling and pain seen in the ENT and dental surgery trials. Nobody has confirmed it by measuring bradykinin in people taking the supplement.
Mucolytic Activity
Laboratory studies show it can break apart the proteins that make airway mucus thick, which is the proposed reason it has been tried for congestion. None of the references on this page tested it in lung conditions such as bronchitis or COPD.
Stomach Acid, Enteric Coating and the Absorption Question
Serrapeptase is a protein, and stomach acid destroys proteins, which is why capsules are usually enteric coated to hold the enzyme until it reaches the intestine. The larger unsettled question is whether an intact enzyme of this size is then absorbed into the bloodstream in amounts that could do anything, and that has never been convincingly shown. It is the main reason to stay cautious about every claim on this page, and it is why a product without an enteric coating is unlikely to be worth taking at all.
Clinical trials
Multicentre, double-blind, randomized trial versus placebo in people with acute or chronic inflammation of the ear, nose and throat, published in the Journal of International Medical Research in 1990.
193 patients being treated for acute or chronic ear, nose and throat inflammation.
Symptoms such as pain, secretion, blockage and swelling improved more with the enzyme than with placebo. The limits matter: this is a 1990 study in patients under medical care, no modern trial of similar size has repeated it, and it says nothing about what the supplement does for a healthy person.
Randomized controlled trial of serratiopeptidase after surgical removal of impacted third molars (wisdom teeth), published in BMC Oral Health in 2021.
Adults having impacted wisdom teeth surgically removed.
Swelling and pain after the operation were lower in the serratiopeptidase group. This is a single trial in one narrow surgical setting, so it does not show that the supplement reduces everyday swelling or pain in healthy people.