Interactions on record — worth a quick check against your medications. Based on 1 of 3 ingredients. Check your meds →
Dietary supplement

Chitoson Plus 1300 mg Ingredients & Drug Interactions

by Universal Nutrition / Universal Naturals

Chitoson Plus 1300 mg label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Chitoson Plus 1300 mg against your medications. The heart of this page is the interaction checker and the full interaction report — how this product’s ingredients may interact with prescription and over-the-counter medicines you may be taking.

Around that, we add a pharmacist’s high-level view of the product as a whole — what’s inside, the evidence for its stated use, how transparent the label is, and what safety data exists — so you can see the full picture in one place. It’s educational information from our licensed clinical databases and the clinical staff at HelloPharmacist — not medical advice — and we don’t sell or endorse products. Our editorial policy

The interaction bottom line Most serious interaction: Moderate

Chitoson Plus 1300 mg is a dietary supplement by Universal Nutrition / Universal Naturals with 3 active ingredients. Its ingredients are commonly taken for weight management, lowering cholesterol, wound care.Based on those ingredients, 3 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Chitosan. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Chitoson Plus 1300 mg by Universal Nutrition / Universal Naturals

Ask about any prescription or over-the-counter medication and we check it for interactions with Chitoson Plus 1300 mg by Universal Nutrition / Universal Naturals — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Chitoson Plus 1300 mg by Universal Nutrition / Universal Naturals

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 16, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains 3 active ingredients. Chitosan is a fiber derived from shellfish shells; it's used to support weight management and may help with recovery after surgery.

Psyllium and oat bran are both soluble fibers that support digestive health and cholesterol levels. The capsule also contains gelatin, magnesium stearate, and dicalcium phosphate as inactive ingredients that help hold the capsule together and improve how it flows during manufacturing.

Does it work?

Moderate evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Moderate

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: weight loss support.
  • We looked for evidence on: Obesity, weight management, cholesterol support.
  • The strongest evidence on file: Chitosan is rated "Possibly Effective" for Obesity (Natural Medicines).

Chitosan is possibly effective for weight management and for supporting recovery after surgery, according to clinical evidence. It may also help with blood pressure.

For Crohn disease and dry eye, there isn't enough reliable evidence yet to rate how well it works. Psyllium and oat bran have roles in digestive health, but effectiveness ratings for those ingredients are not on file in our data.

The evidence, ingredient by ingredient Chitosan

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Chitosan is generally well tolerated in the short term, though quality safety evidence is limited. The most common side effects are constipation, diarrhea, gas, stomach discomfort, and nausea.

Some people report dryness of the throat or fatty stools (steatorrhea). One person with kidney failure reported itching during treatment, though it's unclear if chitosan was the cause.

Because chitosan comes from shellfish shells, it's not suitable if you have a shellfish allergy. There isn't enough safety data to use this product during pregnancy or while breastfeeding — the facts advise against it.

Talk with your doctor or pharmacist about whether this product is right for you if you are pregnant, nursing, or planning to become pregnant.

Side effects, ingredient by ingredient Chitosan

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 1 of the 1 matched ingredient can interact with medications — Chitosan.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs.
  • For scale: 3 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Check with your doctor or pharmacist before taking this product if you use warfarin (a blood thinner), because chitosan may increase your bleeding risk. Also verify it's okay if you take acyclovir (an antiviral for herpes or shingles), since chitosan can reduce how much of that drug your body absorbs.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Chitoson Plus may be worth considering if you're interested in fiber supplementation for weight or digestive support, but you need to check your medications first — especially if you take warfarin or acyclovir. Shellfish allergies are a reason to skip it.

Before you start, talk with your doctor or pharmacist to make sure it fits your health picture and won't interfere with anything you're taking.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 1 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Oct 27, 2014.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Chitoson Plus 1300 mg, straight from the product label.

Brand Universal Nutrition / Universal Naturals
Barcode (UPC) 039442047403
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Oct 27, 2014
DSLD ID 38082
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Chitoson Plus 1300 mg by Universal Nutrition / Universal Naturals, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
30
UPC/BARCODE
039442047403
IngredientAmount% DV
Chitosan1 Gram(s)--
Psyllium150 mg--
Oat Bran150 mg--

Other ingredients: Gelatin, Magnesium Stearate, Dicalcium Phosphate

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Precautions

Not to exceed 6 capsules per day.

Contains shellfish (crab/shrimp shell), wheat.

WARNING: This product is not for use by anyone under the age of 18.

Do not take this if you have or are at risk for any medical condition or disease.

Please consult with a physician before using this product, especially if you are using any prescription drug, over-the-counter medication, or supplements.

Immediately discontinue use if any side effects occur. California Residents Proposition 65 Warning: This product contains a substance known to the State of California to cause birth defects or other reproductive harm.

Keep out of reach of children.

Athletes should consult with their sanctioning authority before use. Do not exceed recommended dose.

Made in a GMP facility on equipment that processes milk, soy, egg, peanuts, tree nuts, fish, shellfish, and wheat. Contains shellfish (crab/shrimp shell), wheat.

Suggested/Recommended/Usage/Directions

As with all weight loss regimens, be sure to maintain a well balanced diet, and to take plenty of fiber and water.

Recommended Use: Take 1-2 capsules with 12 oz. of water before each meal, or as directed by a Healthcare professional.

General

B2213-G-31474

Storage

Keep this bottle tightly closed in a cool, dry place away from direct heat, sunlight and moisture.

General Statements

100% GUARANTEE: If not completely satisfied, return remainder of product and receipt to place of purchase within 30 days for immediate refund or exchange.

Natural Dietary Fiber

USA

MADE IN THE U.S.A.

732-545-3130

FDA Disclaimer Statement

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

Brand IP Statement(s)

(C)2013UniversalNutrition

Formulation

Balanced Nutritional Formulas

FDA Statement of Identity

Dietary Supplement

Formula

Contains shellfish (crab/shrimp shell), wheat.

Is this label outdated? Report a formula or label change and our pharmacy team will review it.

See for yourself

Chitoson Plus 1300 mg by Universal Nutrition / Universal Naturals label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

Chitoson Plus 1300 mg label

Label images are published by the NIH Dietary Supplement Label Database for the version of this product on file. Always read your actual product label.

View the full label (PDF)
What’s inside

The Ingredients in Chitoson Plus 1300 mg by Universal Nutrition / Universal Naturals

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Servings per container30 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Chitosan

Interacts with
3 drugs
1 Gram(s) per serving

Chitosan is a fiber-like substance made from the shells of shrimp, crabs, and other shellfish, often marketed for weight loss and cholesterol. The evi...

Chitosan monograph & interactions

Psyllium

150 mg per serving

Oat Bran

150 mg per serving

Other (inactive) ingredients: Gelatin, Magnesium Stearate, Dicalcium Phosphate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Chitoson Plus 1300 mg by Universal Nutrition / Universal Naturals Drug Interactions

Want to check YOUR meds against Chitoson Plus 1300 mg?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

 Go to the checker
3Drugs
3 Moderate

Ingredients driving the most interactions

Chitosan 3

Individual Drug Interactions

The ingredients in Chitoson Plus 1300 mg interact with 3 drugs. Click any drug to see the details.

1 of the 3 ingredients in Chitoson Plus 1300 mg interact with drugs. Each result below shows which ingredient is responsible. Chitosan

Each ingredient & the kinds of drugs it affects

For each ingredient in Chitoson Plus 1300 mg with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

Chitosan2 drug types · 3 drugs

Acyclovir (Zovirax)

Chitosan can reduce the absorption of acyclovir, potentially increasing the risk for treatment failure.
Clinical research in humans shows that taking chitosan along with acyclovir 200 mg reduces acyclovir absorption. Concomitant administration of chitosan 400 mg or 1000 mg reduced the acyclovir area under the curve (AUC) and peak plasma concentration by about 30% and 40%, respectively, compared with control. Concomitant administration with chitosan 1000 mg also increased time to peak concentration from 1 hour to 2 hours. In vitro research suggests that the mechanism for reduced absorption is due to acyclovir entrapment in chitosan-mucus complexes, which reduces intestinal absorption.

Likelihood Possible Evidence B
Warfarin (Coumadin)

Theoretically, chitosan might increase the risk of bleeding when taken with warfarin.
In a case report, a patient taking warfarin had a significantly increased international normalized ratio (INR) after starting chitosan 1200 mg daily. The INR normalized after chitosan was discontinued and vitamin K was administered. The patient once again started taking chitosan and again had a significant increase in INR. The INR stabilized again once chitosan was discontinued. Researchers theorize that this interaction might occur because chitosan decreases absorption of fat-soluble vitamins, including vitamin K, which could increase the anticoagulant effect of warfarin.

Likelihood Possible Evidence D
Chitosan full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Chitoson Plus 1300 mg, from the product label.

Universal Nutrition / Universal Naturals

Pharmacist Counseling Corner

Chitoson Plus 1300 mg by Universal Nutrition / Universal Naturals: Common Questions

Does Chitoson Plus 1300 mg by Universal Nutrition / Universal Naturals interact with any medications?
Yes. Based on its ingredients, Chitoson Plus 1300 mg has a known interaction with 3 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Chitoson Plus 1300 mg contains 3 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
I have a shellfish allergy — can I take this?
No. Chitosan is made from shellfish shells, so this product isn't safe for you if you have a shellfish allergy. Talk with your pharmacist about fiber alternatives that don't come from shellfish.
What are the most common side effects?
The most common ones are constipation, diarrhea, gas, stomach discomfort, and nausea. Some people also report a dry throat or fatty stools. These tend to be mild and short-lived.
Can I take this while I'm pregnant or nursing?
Not based on the safety data we have. There isn't enough information to know whether it's safe during pregnancy or breastfeeding, so the facts advise against it. Talk with your doctor or pharmacist for personalized guidance.
Does this actually help with weight loss?
Chitosan is possibly effective for weight management according to clinical evidence, though the evidence isn't conclusive. Results vary from person to person, and it works best as part of a broader approach to diet and exercise.
Why does this product have psyllium and oat bran in it?
Both are soluble fibers that support digestive health and cholesterol levels. They work alongside chitosan to provide broad fiber supplementation.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Not sure if Chitoson Plus 1300 mg is safe with your meds?

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Chitoson Plus 1300 mg label
Go deeper

The Full Monographs Behind Chitoson Plus 1300 mg’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Herb & supplement monograph

Chitosan

Interacts with 3 drugs

Chitosan is a fiber-like substance made from the shells of shrimp, crabs, and other shellfish, often marketed for weight loss and cholesterol. The evidence for these benefits is weak, and an...

Read the full Chitosan monograph →
Sources

Sources & How We Checked

Chitoson Plus 1300 mg's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 17 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Chitosan 17 references
  1. Jing SB, Li L, Ji D, et al. Effect of chitosan on renal function in patients with chronic renal failure. J Pharm Pharmacol 1997;49:721-3. PubMed
  2. Pittler MH, Abbot NC, Harkness EF, Ernst E. Randomized, double-blind trial of chitosan for body weight reduction. Eur J Clin Nutr 1999;53:379-81. PubMed
  3. Ho SC, Tai ES, Eng PH, et al. In the absence of dietary surveillance, chitosan does not reduce plasma lipids or obesity in hypercholesterolaemic obese Asian subjects. Singapore Med J 2001;42:6-10.
  4. Bokura H, Kobayashi S. Chitosan decreases total cholesterol in women: a randomized, double-blind, placebo-controlled trial. Eur J Clin Nutr 2003;57:721-5. PubMed
  5. Mhurchu CN, Poppitt SD, McGill AT, et al. The effect of the dietary supplement, Chitosan, on body weight: a randomised controlled trial in 250 overweight and obese adults. Int J Obes Relat Metab Disord 2004;28:1149-56. PubMed
  6. Huang SS, Sung SH, Chiang CE. Chitosan potentiation of warfarin effect. Ann Pharmacother 2007;41:1912-4. PubMed
  7. Tsai, G. J. and Su, W. H. Antibacterial activity of shrimp chitosan against Escherichia coli. J Food Prot. 1999;62(3):239-243. PubMed
  8. Wuolijoki, E., Hirvela, T., and Ylitalo, P. Decrease in serum LDL cholesterol with microcrystalline chitosan. Methods Find.Exp Clin Pharmacol. 1999;21(5):357-361. PubMed
  9. Nelson, J. L., Alexander, J. W., Gianotti, L., Chalk, C. L., and Pyles, T. Influence of dietary fiber on microbial growth in vitro and bacterial translocation after burn injury in mice. Nutrition 1994;10(1):32-36.
  10. Schiller RN, Barrager E, Schauss EA, and et al. A randomized, double-blind, placebo-controlled study examining the effects of a rapidly soluble chitosan dietary supplement on weight loss and body composition in overweight and mildly obese individuals. J
  11. Koide, S. S. Chitin-chitosan: properties, benefits and risks. Nutrition Research 1998;8(6):1091-1101. DOI
  12. Maezaki Y, Tsuji K, Nakawa, and et al. Hypocholesterolaemic effect of chitosan in adult males. Biosc Biochem Biotech 1993;57:1439-1444.
  13. Kubbinga M, Nguyen MA, Staubach P, et al. The influence of chitosan on the oral bioavailability of acyclovir-a comparative bioavailability study in humans. Pharm Res 2015;32(7):2241-9. PubMed
  14. Jull AB, Ni Mhurchu C, Bennett DA, et al. Chitosan for overweight or obesity. Cochrane Database Syst Rev 2008;(3):CD003892. PubMed
  15. Schmidl D, Werkmeister R, Kaya S, et al. A Controlled, Randomized Double-Blind Study to Evaluate the Safety and Efficacy of Chitosan-N-Acetylcysteine for the Treatment of Dry Eye Syndrome. J Ocul Pharmacol Ther. 2017;33(5):375-382.
  16. Moraru C, Mincea MM, Frandes M, Timar B, Ostafe V. A meta-analysis on randomised controlled clinical trials evaluating the effect of the dietary supplement chitosan on weight loss, lipid parameters and blood pressure. Medicina (Kaunas). 2018;54(6):109. PubMed
  17. García MA, Hensler G, Al-Gousous J, Pielenhofer J, Wagner M, Lennernäs H, Langguth P. Novel food drug interaction mechanism involving acyclovir, chitosan and endogenous mucus. Drug Metab Pharmacokinet. 2023;49:100491. PubMed

See these in context on the Chitosan monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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