Other Name(s):

Ascorbate de Chitosane, Chitosan Ascorbate, Chitosane, Chitosane Déacétylé, Chitosane Mono-Carboxyméthylé, Deacetylated Chitosan, Enzymatic Polychitosamine Hydrolisat, HEP-30, Hydrolisat Enzymatique de Polychitosamine, Mono-Carboxymethylated Chitosan, N-Carboxybutyl Chitosan, N-Carboxybutyl Chitosane, N,O-Sulfated Chitosan, O-Sulfated N-Acetylchitosan, Quitosano, Sulfated N-Carboxymethylchitosan, Sulfated O-Carboxymethylchitosan, Trimethyl Chitosan Chloride.


Chitosan is a sugar that is obtained from the hard outer skeleton of shellfish, including crab, lobster, and shrimp. It is used for medicine.

Chitosan is used to treat obesity, high cholesterol, and Crohn's disease. It is also used to treat complications that kidney failure patients on dialysis often face, including high cholesterol, “tired blood” (anemia), loss of strength and appetite, and trouble sleeping (insomnia).

Some people apply chitosan directly to their gums to treat inflammation that can lead to tooth loss (periodontitis), or chew gum that contains chitosan to prevent “cavities” (dental caries).

In an effort to help “donor tissue” rebuild itself, plastic surgeons sometimes apply chitosan directly to places from which they have taken tissue to be used elsewhere.

In pharmaceutical manufacturing, chitosan is used as a filler in tablets; as a carrier in controlled-release drugs; to improve the way certain drugs dissolve; and to mask bitter tastes in solutions taken by mouth.

How does it work?

Chitosan is extracted from the shells of shrimp, lobster, and crabs. It is a fibrous substance that might block absorption of dietary fat and cholesterol.


What causes tooth decay? See Answer

Uses & Effectiveness

Possibly Effective for...

  • Gum disease (periodontitis). Some research suggests that applying chitosan ascorbate directly to the gums seems to help in the treatment of periodontitis.
  • Plastic surgery. Some research suggests that applying N-carboxybutyl chitosan directly to the affected area seems to help wound healing and reduce scar formation after plastic surgery.
  • Kidney failure. Some research suggests that taking chitosan by mouth may reduce high cholesterol, help to correct anemia, and improve physical strength, appetite, and sleep in people with kidney failure who are receiving long-term hemodialysis.

Insufficient Evidence to Rate Effectiveness for...

  • Crohn's disease (an intestinal disorder). Early research shows that taking a combination of chitosan and ascorbic acid by mouth might help people with Crohn's disease.
  • Dental cavities. There is some evidence that a chewing gum containing chitosan or using a mouthwash containing chitosan can decrease the number of cavity-causing bacteria in the mouth. However, there is no reliable evidence that these products actually prevent cavities.
  • Dental plaque. Early research suggests that rinsing with a chitosan mouth wash for 2 weeks reduces formation of plaque.
  • High cholesterol. There is conflicting evidence about the effectiveness of chitosan for lowering cholesterol. Some research shows that taking chitosan does not seem to significantly decrease total cholesterol or “bad” low-density lipoprotein (LDL) in people with high cholesterol. However, other research shows that chitosan seems to lower cholesterol in people with or without high cholesterol. Also, some combination products containing chitosan also seem to reduce cholesterol levels in obese people with or without high cholesterol. Those combination products include: a supplement containing chitosan, garcinia, and chromium and another supplement containing chitosan, guar meal, ascorbic acid, and other micronutrients.
  • Weight loss. There is conflicting evidence about the effectiveness of chitosan for weight loss. Some research suggests that combining chitosan with a calorie-restricted diet might result in a small amount of weight loss. But taking chitosan, without cutting calories, doesn't seem to cause weight loss.
    Many studies on chitosan have design flaws that make their results questionable. When only the higher quality studies are analyzed, the effect of chitosan on weight loss is minimal, only about 0.5 kg (about 1.1 pounds) when taken for 1-6 months. This may not make much difference to health.
  • Wound healing. Early research suggests that applying chitosan to skin grafts might improve wound healing and help nerves regrow.
  • Other conditions.
More evidence is needed to rate the effectiveness of chitosan for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).

Side Effects

Chitosan is POSSIBLY SAFE for most people when taken by mouth for up to six months or when applied to the skin. When taken by mouth, chitosan might cause mild stomach upset, constipation, or gas.


Mouth Problems: TMJ, Canker Sores, Painful Gums and More See Slideshow

Special Precautions & Warnings

Pregnancy and breast-feeding: There is not enough reliable information about the safety of taking chitosan by mouth if you are pregnant or breast-feeding. Stay on the safe side and avoid use.

Shellfish allergy: Chitosan is taken from the outer skeleton of shellfish. There is a concern that people with allergies to shellfish might also be allergic to chitosan. However, people who are allergic to shellfish are allergic to the meat, not the shell. So some experts believe that chitosan may not be a problem for people with shellfish allergy.


Warfarin (Coumadin)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Warfarin is a blood thinner. There is some concern that taking chitosan might increase the blood-thinning effects of warfarin (Coumadin). Taking chitosan with warfarin (Coumadin) could increase the chance of bruising or bleeding. If you take warfarin, avoid taking chitosan.


The following doses have been studied in scientific research:


  • For reducing high cholesterol and improving anemia, physical strength, appetite, and sleep in people with renal failure who are undergoing hemodialysis: 1.35 grams of chitosan three times daily.

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