Chitosan

Snapshot

Indications	Contraindications
Weight management¹ Lipid profile support¹ Glycemic regulation¹ Dental bleeding control² Donor-site bleeding³	Shellfish allergy⁴ Pregnancy or breastfeeding⁵ Warfarin therapy¹

Chitosan is a derivative of chitin extracted from crustacean shells and reishi mushroom cell walls¹. It acts as an insoluble dietary fiber, though human studies suggest its marketed fat-binding effect is unlikely¹. People take it for lipid lowering, glycemic control, and weight management, where results are mixed¹. Topical dressings are used for bleeding control, including in patients on antiplatelet or anticoagulant therapy².

For wound healing, a systematic review found chitosan does not slow healing, with benefit over gauze in only some trials⁶. In healthy adults, a 2026 pilot controlled study found oral crustacean-derived chitosan lowered circulating microplastics versus placebo, and the authors call the evidence preliminary⁷. Products listing chitosan are mostly capsules and powders; see Form comparison.

Shellfish allergy is the most consequential caution because most products derive from crustacean shells; product labels in the United States carry this warning⁴. Memorial Sloan Kettering Cancer Center (MSKCC) cites a case report of increased warfarin effect, so anticoagulated patients are a group for prescriber awareness rather than a settled exclusion¹.

Last updated October 16, 2026. Read how we make monographs.

In the full monograph

40 sources, 36 studies

When to useThe situations practitioners use it for, each with the reason and the study behind it.
SafetyWho should avoid it, who needs extra care, and the side effects reported in studies.
InteractionsThe medicines and supplements it interacts with, the effect of each, and what labeling says to watch.
Protocol notesThe doses used in studies, how and when they were taken, and how the forms on the market compare.
How it worksWhat it is and how it works in the body, in plain terms.
Published studiesThe studies behind each use, popular claims checked against them, and trials still under way.
Word of mouthWhat patients and practitioners report online, kept separate from the clinical evidence.
Clinical perspectiveA closing read of where the evidence is solid, where it is thin, and what has not been studied.

Snapshot

In the full monograph

Sources