Health Guide


What is it?

Natto is a common food in Japan. It is helpful for heart disease. It may also be used to prevent osteoporosis ("brittle bones") and can be used with other cancer treatments.

Other names for natto include: nattokinase, subtilisin NAT, and sutilains.

Ask your doctor, nurse, or pharmacist if you need more information about this medicine or if any information in this leaflet concerns you.

Before Using:

Tell your doctor if you

  • are taking medicine or are allergic to any medicine (prescription or over-the-counter (OTC) or dietary supplement)
  • are pregnant or plan to become pregnant while using this medicine
  • are breastfeeding
  • have other health problems, such as high blood pressure or heart or blood vessel disease


Talk to your caregivers about how much natto you should take. The amount depends on the strength of the medicine and the reason you are taking natto. If you are using this medicine without instructions from your caregiver, follow the directions on the medicine bottle. Do not take more medicine or take it more often than the directions tell you to.

To store this medicine:

Keep all medicine locked up and away from children. Store medicine away from heat and direct light. Do not store your medicine in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down and not work the way it should work. Throw away medicine that is out of date or that you do not need. Never share your medicine with others.

Drug and Food Interactions:

Do not take natto without talking to your doctor first if you are taking:

  • Blood thinning medicine (example: heparin, warfarin (Coumadin(R)))


  • Before taking natto, tell your doctor if you are pregnant or breastfeeding

Side Effects:

Stop taking your medicine right away and talk to your doctor if you have any of the following side effects. Your medicine may be causing these symptoms which may mean you are allergic to it.

  • Breathing problems or tightness in your throat or chest
  • Chest pain
  • Skin hives, rash, or itchy or swollen skin

Other Side Effects:

You may have the following side effects, but this medicine may also cause other side effects. Tell your doctor if you have side effects that you think are caused by this medicine.

  • Any unusual bleeding or bruising


Fujita M, Hong K, Ito Y et al: Thrombolytic effect of nattokinase on a chemically induced thrombosis model in rat. Biol Pharm Bull 1995; 18(10):1387-1391.

Sumi H, Kubota H, Yanagisawa Y et al: Vitamin K (menaquinone-7) and nattokinase activity in the traditional fermented soybeans food "Natto." Fibrinolysis and Proteolysis 2000; 14(s1):62.

Urano T, Ihara H, Umemura K et al: The pro-fibrinolytic enzyme subtilisin NAT purified from Bacillus subtilis cleaves and inactivates plasminogen activator inhibitor type 1. J Bio Chem 2001; 276(27):24690-24696.

Last Updated: 7/4/2018
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