What Is Serrapeptase?

The silkworm enzyme believed to reduce pain and inflammation

Serrapeptase capsules and tablets

Verywell / Anastasia Tretiak

Serrapeptase is an enzyme derived from Serratia E-15, an intestinal bacteria a silkworm uses to dissolve its cocoon once it transforms into a moth.

There's limited research on serrapeptase benefits, but some practitioners believe it exerts anti-inflammatory effects to reduce pain and swelling, especially in the upper respiratory tract. Serrapeptase is also used to relieve pain following minor surgery.

Serrapeptase was first isolated by scientists in Japan in the 1960s and soon after became a bestselling drug there (brand name Danzan), later finding its way onto drugstore shelves in Europe and North America as a dietary supplement.

Doubts about the drug's efficacy led its manufacturer, Takeda, to voluntarily withdraw it in 2011. Despite the recall, there are plenty of manufacturers that still produce serrapeptase supplements and point to their efficacy in clinical studies.

Also Known As

  • Butterfly extract
  • Serratiopeptidase
  • Silkworm enzyme

What Is Serrapeptase Used For?

Proponents of alternative medicine claim that serrapeptase can help treat a wide range of medical conditions. Chief among these are:

Claims of health benefits of alternative treatments often extend beyond a substance's intended use, encompassing what seems to be an almost encyclopedic range of medical conditions.

With serrapeptase, proponents claim the enzyme can dissolve blood clots, alleviate symptoms of arthritis, prevent atherosclerosis (hardening of the arteries), and treat diabetes, asthma, inflammatory bowel disease (IBD), leg ulcers, and fibrotic breast disease.

To date, there is no evidence that it can treat any of these conditions.

That is not to say there is no benefit to serrapeptase use. However, studies that make up the current body of research are often poorly designed or too small to be statistically relevant.

Here are a few that provide some of the more compelling pieces of evidence in support of serrapeptase use.

Oral Surgery

A small study published in the International Journal of Oral and Maxillofacial Surgery suggests that serrapeptase may help alleviate pain and swelling resulting from dental surgery.

The study involved 24 healthy people, all of whom underwent the surgical removal of impacted molars. Half were given 1,000 milligrams (mg) of Tylenol (acetaminophen) plus 5 mg of serrapeptase three times a day for seven days, while the other group received the same amount of Tylenol with a placebo.

According to the researchers, in the seven days following surgery, the serrapeptase group had less cheek swelling (as measured by calipers) and pain intensity (as measured by numeric scale) than those given the placebo.

Despite the promising results, the conclusions were limited by the size of the study and the subjective nature of pain measurements.

Upper Respiratory Symptoms

Serrapeptase has long been touted for its ability to alleviate throat pain, hoarseness, and sinus congestion associated with upper respiratory infections and illnesses.

According to a 2017 review published in the Asian Journal of Pharmacological Science, serrapeptase exerts effects similar to cyclooxygenase-1 (COX-1) and cyclooxygenase-1 (COX-2) inhibitor drugs like Aleve (naproxen) and Celebrex (celecoxib).

In addition to alleviating inflammation, serrapeptase also appears to break down exudates (fluids that seep out of tissue as a result of inflammation).

By exerting anti-inflammatory, anti-exudate, and analgesic (pain-relieving) properties, serrapeptase could very well alleviate common upper respiratory tract symptoms. However, to date, there is little qualitative evidence of such benefits.

Of the available research, a 2003 study in the journal Respiralogy reported that four weeks of serrapeptase given at a dose of 30 mg daily reduced the amount and thickness of mucus coughed up by people with chronic bronchitis.

Despite flaws in the study design, the findings were significant enough to suggest that serrapeptase may play an important role in mucus clearance in people with chronic obstructive pulmonary disease (COPD) and other respiratory diseases.

Possible Side Effects

While serrapeptase has been used for up to four weeks in clinical research, little is known about its long-term safety. Common side effects tend to be mild but may include:

  • Nausea
  • Stomach pain
  • Muscle and joint pain
  • Cough
  • Rash
  • Hypersensitivity (allergic) reactions
  • Pneumonitis
  • Increase in abscess size

Although it is said to alleviate upper respiratory symptoms, serrapeptase has been known to cause pneumonitis (lung inflammation) in some. The condition appears triggered by a sudden drop in white blood cells called eosinophils and occurs mostly in elderly adults.

A 2016 report in the Journal of Clinical and Diagnostic Research also suggests that serrapeptase may increase the size of an abscess, in part by breaking down exudates in surrounding tissues.

Serrapeptase should not be used if you have an abscess of any sort, including an abscessed tooth. Doing so may facilitate the further spread of infection.

The safety of serrapeptase in pregnant women, nursing mothers, and children has not been established. Given the potential harms and uncertain benefits, it may be best that these groups avoid serrapeptase.


Serrapeptase may interfere with blood clotting and should be avoided if you are taking blood thinners like Coumadin (warfarin) or Plavix (clopidogrel). Taking them together may cause easy bruising or bleeding.

For this same reason, you should stop using serrapeptase two weeks before a scheduled surgery to avoid excessive bleeding.

Serrapeptase tablets

Verywell / Anastasia Tretiak

Dosage and Preparation

There are no guidelines for the appropriate use of serrapeptase. Doses of up to 60 mg daily have been used safely in short-term studies.

Serrapeptase supplements are readily sourced online and in certain health food and nutritional supplement stores. Most are sold as capsules, gelcaps, or enteric-coated tablets with doses ranging from 34 mg (20,000 international units, or IU) to 500 mg (300,000 IU). However, a dose of 60,000 IU to 120,000 IU (about 100-200 mg) has been used in studies.

As a general rule, it is best to avoid high-dose formulations. Not only are they more costly, but there is no evidence that higher doses are any more effective than lower doses.

Always use the smallest dose possible and never exceed the recommended dose on the product label. If side effects persist or worsen, stop taking serrapeptase and advise your healthcare provider.

To avoid stomach upset, take this supplement with food or choose an enteric-coated tablet, which dissolves lower down in the intestinal tract. This can also help slow the breakdown and deactivation of serrapeptase by stomach acids.

What to Look For

Dietary supplements are not strictly regulated in the United States. To ensure the highest quality, opt for brands that have been tested by an independent certifying body like U.S. Pharmacopeia (USP), NSF International, or ConsumerLab.

If you are strictly vegetarian or vegan, double-check that gelcaps are made of a vegetable-based gelatins rather than animal-derived bovine or porcine gelatin.

Serrapeptase can be stored safely at room temperature. You should discard any supplement that has expired or shows signs of spoilage or deterioration (including changes in color, texture, or smell).

Frequently Asked Questions

  • What is serrapeptase?

    Serrapeptase (also known as serratiopeptidase and serralysin) is an enzyme that was discovered in the intestines of the Bombyx mori silkworm back in the 1960s. Alternative practitioners contend that it has medical properties and can be used to treat pain and inflammation.

  • What is serrapeptase used for?

    Serrapeptase was originally marketed under the brand name Danzan in the 1960s and is claimed by some to prevent or treat a wide range of health conditions, including:

  • How much serrapeptase should I take?

    There are no guidelines for the appropriate use of serrapeptase in any form. Doses of up to 60 milligrams (mg) daily have been used safely in short-term studies.

  • What are the side effects of serrapeptase?

    Serrapeptase appears well tolerated, although little is known about its long-term safety. Side effects may include:

    • Nausea
    • Stomach upset
    • Muscle aches
    • Joint pain
    • Cough
    • Rash (uncommon)
  • Who should not take serrapeptase?

    Serrapeptase should be avoided in people with an abscessed tooth as there is evidence it can promote the spread of infection to deeper tissues. Children and people who are pregnant or breastfeeding should also avoid serrapeptase due to the lack of safety research.

  • Are there drug interactions with serrapeptase?

    Because serrapeptase can inhibit blood clotting, it should be avoided in people who take anticoagulants like Coumadin (warfarin) and Plavix (clopidogrel), as the combination may increase the risk of bruising and bleeding.

  • Is there any evidence serrapeptase works?

    A 2013 review in the International Journal of Surgery involving 24 different studies concluded that "the existing scientific evidence for serrapeptase is insufficient to support its use as an analgesic and health supplement."

5 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Bhagat S, Agarwal M, Roy V. Serratiopeptidase: a systematic review of the existing evidence. Int J Surg. 2013;11(3):209-17. doi:10.1016/j.ijsu.2013.01.010

  2. Health Science Authority. HSA Updates on the Phasing-Out of Serratiopeptidase-Containing Preparations as Medicinal Products.Singapore: November 29, 2011.

  3. Monograph: Serrapeptase. Natural Health Products Ingredients Database. Health Canada. September 25, 2018.

  4. Jadhav SB, Shah N, Rathi A, Rathi V, Rathi A. Serratiopeptase: insights into therapeutic applications. Biotechnol Rep (Amst). 2020 Dec:28:e00544. doi:10.1016/j.btre.2020.e00544

  5. Rajaram P, Bhattarcharjee A, Ticku S. Serrotiopeptase - a cause for spread of infection. J Clin Diagn Res. 2016 Aug;10(8):ZD31-2. doi:10.7860/JCDR/2016/21388.8302

Additional Reading

By Cathy Wong
Cathy Wong is a nutritionist and wellness expert. Her work is regularly featured in media such as First For Women, Woman's World, and Natural Health.