Diet Chitosan 250 mg Ingredients & Drug Interactions
by Source Naturals
What is this page for?
First and foremost: checking Diet Chitosan 250 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
Diet Chitosan 250 mg is a dietary supplement by Source Naturals with 2 active ingredients. Its ingredients are commonly taken for constipation, diarrhea, high cholesterol.Based on those ingredients, 2,025 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Dietary Fiber, Chitosan. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against Diet Chitosan 250 mg by Source Naturals
Ask about any prescription or over-the-counter medication and we check it for interactions with Diet Chitosan 250 mg by Source Naturals — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of Diet Chitosan 250 mg by Source 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.
What’s inside
Full disclosure
Diet Chitosan 250 mg contains one active ingredient: chitosan, a fiber derived from shellfish shells. It's marketed as a weight-management supplement.
The capsule also contains microcrystalline cellulose, gelatin, magnesium stearate, and silica as inactive ingredients (binders and fillers).
Does it work?
Moderate evidence
Chitosan has possibly effective evidence for obesity and blood pressure support, according to the data we hold. For postoperative recovery, the evidence is also rated possibly effective.
However, for Crohn disease and dry eye, we don't have reliable evidence to rate its usefulness — the research is insufficient. Talk with your doctor about whether it fits your health goals.
How safe is it?
Well-documented data
Chitosan is generally well tolerated short-term, though quality evidence is limited. The most common side effects are constipation, diarrhea, flatulence, stomach discomfort, and nausea.
A few people have reported throat dryness or excessive fat in the stool (steatorrhea). Because chitosan comes from shellfish shells, anyone with a shellfish allergy should avoid it.
There isn't enough safety data to use chitosan during pregnancy or while breastfeeding — talk with your doctor or pharmacist about whether it's right for you.
Meds to double-check
Moderate interaction found
Before starting Diet Chitosan, double-check with your doctor or pharmacist if you take warfarin (Coumadin) — it may raise your bleeding risk — or acyclovir (Zovirax) — it may reduce how well the antiviral works. Both are Moderate-severity interactions.
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.
Diet Chitosan 250 mg may help with weight management or blood pressure, but it interacts with blood thinners and antiviral drugs. If you take warfarin or acyclovir, check with your doctor or pharmacist before adding it.
It's well tolerated for short-term use in most people, though digestive side effects are common. Run your exact medications through our checker on this page to be sure.
Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI
Assessment coverage: 2 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jan 25, 2020.
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
General information
Key facts about Diet Chitosan 250 mg, straight from the product label.
| Brand | Source Naturals |
|---|---|
| Barcode (UPC) | 021078012467 |
| Net contents | 240 Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Jan 25, 2020 |
| DSLD ID | 214124 |
| Product type | Fiber And Other Nutrients |
| Supplement form | Capsule |
| Dietary claims / uses | Nutrient, All Other, Structure/Function |
| Intended target group(s) | Adult (18 - 50 Years), Gluten Free, Dairy Free, Sugar Free |
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 Diet Chitosan 250 mg by Source Naturals, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| Calories | 10 Calorie(s) | -- |
| Total Carbohydrates | 1 Gram(s) | 1% |
| Dietary Fiber | 1 Gram(s) | 4% |
| Chitosan | 1 Gram(s) | -- |
Other ingredients: Microcrystalline Cellulose, Gelatin, Magnesium Stearate, Silica
Tap any ingredient to jump to its full detail below.
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.
Formula
Dietary Supplement
Breakthrough fiber
Chitosan, a fiber derived from chitin in shellfish, is a nondigsestible aminopolysaccharide. Chitosan is produced by removing acetyl groups from chitin through a process called deacetylation. This process enhances the activity of chitosan by improving its solubility in the acidic environment of the stomach. When taken in conjunction with the Maximum Metabolism Weight Loss Plan, body fat may be reduced.
Precautions
Contains shellfish (shrimp, crab, & lobster).
Do not use if either tamper-evident seal is broken or missing.
Keep out of the reach of children.
Caution: If you are pregnant, may become pregnant, breastfeeding, allergic to shellfish or taking any medication, consult your health care professional before using this product. Fat-soluble vitamins (A, E, D or K), essential fatty acids or medications should be taken 4 hours before or after ingesting chitosan to ensure absorption.
Caution: If you are pregnant, may become pregnant, breastfeeding, allergic to shellfish or taking any medication, consult your health care professional before using this product.
Take this product with large amounts of fluid. If you do not drink enough liquid, the product may cause constipation. Discontinue use if intestinal discomfort or constipation occurs.
Suggested/Recommended/Usage/Directions
Suggested Use: 4 capsules 1/2 hour before lunch and 4 capsules 1/2 hour before dinner with 8 ounces of liquid. Drink at least 8 glasses of fluid daily. For best results, take this product in conjunction with the enclosed Maximum Metabolism Weight Loss Plan and a multiple vitamin such as Source Naturals Life Force.
Storage
Store in a cool, dry place.
Formulation
Contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, starch, preservatives, or artificial color, flavor or fragrance.
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.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
Diet Chitosan 250 mg by Source Naturals label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in Diet Chitosan 250 mg by Source Naturals
These are the 2 active ingredients this product is made of. Select any to open its full monograph.
Serving size4 Capsule(s) Dosage formCapsule Servings per container60 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.
Dietary Fiber
Interacts with2,025 drugs
Black psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. I...
Dietary Fiber monograph & interactionsChitosan
Interacts with3 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 evi...
Chitosan monograph & interactionsOther (inactive) ingredients: Microcrystalline Cellulose, Gelatin, Magnesium Stearate, Silica. These complete the product’s ingredient list but are not active constituents.
Diet Chitosan 250 mg by Source Naturals Drug Interactions
HelloPharmacist Interaction Report
Diet Chitosan 250 mg by Source Naturals does interact with medications.
The main concern is through its chitosan content, which can interfere with two important drug types: the antiviral acyclovir (Zovirax) and the blood thinner warfarin (Coumadin). With acyclovir, chitosan reduces how much of the drug your body absorbs, which may make the medication less effective at fighting viral infections.
With warfarin, chitosan may increase bleeding risk — one patient's blood-thinning levels (INR) rose significantly after starting chitosan and normalized only after stopping it and taking vitamin K.
Read the full breakdown — every affected drug type, severity by severity
Both interactions are rated Moderate in severity. Altogether, these interactions span 3 individual medications.
If you take acyclovir or warfarin, or any other prescription medication, check your exact drugs with the search tool on this page before you start chitosan.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against Diet Chitosan 250 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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in Diet Chitosan 250 mg interact with 2,025 drugs. Click any drug to see the details.
2 of the 2 ingredients in Diet Chitosan 250 mg interact with drugs. Each result below shows which ingredient is responsible. Dietary Fiber Chitosan
AcyclovirAvaclyr, Sitavig, Zovirax, Zovirax Injection
How Acyclovir interacts with Diet Chitosan 250 mg — through 2 ingredients. Tap an ingredient for the detail:
ChitosanAcyclovir (zovirax) Moderate
Interaction Summary
Chitosan can reduce the absorption of acyclovir, potentially increasing the risk for treatment failure.
Read the full Chitosan + Acyclovir interactionDietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Acyclovir interactionAlogliptin, MetforminKazano
How Alogliptin, Metformin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Alogliptin, Metformin interactionCanagliflozin, MetforminInvokamet
How Canagliflozin, Metformin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Canagliflozin, Metformin interactionCanagliflozin, Metformin HydrochlorideInvokamet XR
How Canagliflozin, Metformin Hydrochloride interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Canagliflozin, Metformin Hydrochloride interactionCarbamazepineCarbatrol, Carnexiv, Equetro, Tegretol, Tegretol XR
How Carbamazepine interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Carbamazepine (tegretol) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Carbamazepine interactionDapagliflozin Propanediol, MetforminXigduo XR
How Dapagliflozin Propanediol, Metformin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Dapagliflozin Propanediol, Metformin interactionDapagliflozin, Metformin Hydrochloride, Saxagliptin HydrochlorideQternmet XR
How Dapagliflozin, Metformin Hydrochloride, Saxagliptin Hydrochloride interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Dapagliflozin, Metformin Hydrochloride, Saxagliptin Hydrochloride interactionEmpagliflozin, Linagliptin, Metformin HydrochlorideTrijardy XR
How Empagliflozin, Linagliptin, Metformin Hydrochloride interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Empagliflozin, Linagliptin, Metformin Hydrochloride interactionEmpagliflozin, MetforminSynjardy
How Empagliflozin, Metformin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Empagliflozin, Metformin interactionEmpagliflozin, Metformin HydrochlorideSynjardy XR
How Empagliflozin, Metformin Hydrochloride interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Empagliflozin, Metformin Hydrochloride interactionErtugliflozin, Metformin HydrochlorideSegluromet
How Ertugliflozin, Metformin Hydrochloride interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Ertugliflozin, Metformin Hydrochloride interactionGlipizide, MetforminMetaglip
How Glipizide, Metformin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Glipizide, Metformin interactionGlyburide, MetforminGlucovance
How Glyburide, Metformin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Glyburide, Metformin interactionLinagliptin, Metformin HydrochlorideJentadueto XR
How Linagliptin, Metformin Hydrochloride interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Linagliptin, Metformin Hydrochloride interactionLithium Carbonate (prescription Drug)Eskalith, Lithium Carbonate
How Lithium Carbonate (prescription Drug) interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Lithium Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Lithium Carbonate (prescription Drug) interactionMetforminGlucophage, Metformin
How Metformin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Metformin interactionMetformin HydrochlorideRiomet ER
How Metformin Hydrochloride interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Metformin Hydrochloride interactionMetformin, LinagliptinJentadueto
How Metformin, Linagliptin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Metformin, Linagliptin interactionMetformin, RosiglitazoneAvandamet
How Metformin, Rosiglitazone interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Metformin, Rosiglitazone interactionMetformin, SitagliptinJanumet, Janumet XR
How Metformin, Sitagliptin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Metformin, Sitagliptin interactionOlanzapineZyprexa
How Olanzapine interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Olanzapine (zyprexa) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Olanzapine interactionSaxagliptin, Metformin XrKombiglyze
How Saxagliptin, Metformin Xr interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Saxagliptin, Metformin Xr interactionSitagliptin, MetforminZituvimet
How Sitagliptin, Metformin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs, Metformin (glucophage) Moderate
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Sitagliptin, Metformin interactionWarfarinWarfarin
How Warfarin interacts with Diet Chitosan 250 mg — through 2 ingredients. Tap an ingredient for the detail:
ChitosanWarfarin (coumadin) Moderate
Interaction Summary
Theoretically, chitosan might increase the risk of bleeding when taken with warfarin.
Read the full Chitosan + Warfarin interactionDietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Warfarin interactionWarfarin SodiumCoumadin, Panwarfin, Sofarin
How Warfarin Sodium interacts with Diet Chitosan 250 mg — through 2 ingredients. Tap an ingredient for the detail:
ChitosanWarfarin (coumadin) Moderate
Interaction Summary
Theoretically, chitosan might increase the risk of bleeding when taken with warfarin.
Read the full Chitosan + Warfarin Sodium interactionDietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Warfarin Sodium interactionPioglitazone, MetforminActoPlus Met
How Pioglitazone, Metformin interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberMetformin (glucophage), Oral Drugs Moderate
Interaction Summary
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Read the full Dietary Fiber + Pioglitazone, Metformin interaction"phentolamineOraVerse, Rogitine, Ryzumvi
How "phentolamine interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + "phentolamine interaction6-mercaptopurinePurinethol
How 6-mercaptopurine interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + 6-mercaptopurine interactionAbacavirZiagen
How Abacavir interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Abacavir interactionAbacavir Sulfate, Dolutegravir, LamivudineTriumeq
How Abacavir Sulfate, Dolutegravir, Lamivudine interacts with Diet Chitosan 250 mg — through 1 ingredient. Tap an ingredient for the detail:
Dietary FiberOral Drugs Minor
Interaction Summary
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Read the full Dietary Fiber + Abacavir Sulfate, Dolutegravir, Lamivudine interactionEach ingredient & the kinds of drugs it affects
For each ingredient in Diet Chitosan 250 mg with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.
Dietary Fiber
Carbamazepine (Tegretol)
Theoretically, black psyllium might reduce the effects of carbamazepine and increase the risk for convulsions.
Theoretically, black psyllium might reduce carbamazepine absorption. A preliminary study using blond psyllium reported decreased carbamazepine bioavailability due to binding of the drug to psyllium, as well as reduction of available fluid in the gut for dissolution of the drug. This interaction may also occur with black psyllium.
Lithium
Theoretically, taking black psyllium at the same time as lithium might reduce lithium absorption.
The fiber in black psyllium might reduce lithium absorption and plasma levels. Some case reports describe a reduction in plasma lithium levels with concomitant administration of blond psyllium. This was reversed when psyllium was stopped. This interaction may also occur with black psyllium.
Metformin (Glucophage)
Theoretically, black psyllium might increase the therapeutic and adverse effects of metformin.
Animal research shows that concurrent consumption of blond psyllium with metformin slows and increases the absorption of metformin. This interaction may also occur with black psyllium. To avoid changes in absorption, take psyllium 30-60 minutes after metformin.
Olanzapine (Zyprexa)
Theoretically, taking black psyllium at the same time as olanzapine might reduce olanzapine absorption.
The fiber in black psyllium might decrease the absorption of olanzapine. A single case report describes a reduction in the effectiveness of olanzapine when it was concomitantly administered with an unspecified type of psyllium 3 grams orally twice daily. This effect was reversed when psyllium was stopped.
Digoxin (Lanoxin)
Theoretically, taking black psyllium at the same time as digoxin might reduce digoxin absorption and decrease digoxin levels.
Psyllium might bind digoxin in the gut. However, some clinical evidence suggests that psyllium does not impact digoxin absorption.
Ethinyl Estradiol
Theoretically, taking black psyllium at the same time as ethinyl estradiol might alter levels of estradiol.
Concurrent use of blond psyllium with ethinyl estradiol results in a slight increase in the extent of ethinyl estradiol absorption and a slower rate of absorption. This is unlikely to be clinically significant.
Oral Drugs
Theoretically, psyllium might increase, decrease, or have no effect on the absorption of oral drugs.
Psyllium seems to have variable effects on drug absorption. To avoid changes in absorption, take psyllium 30-60 minutes after oral medications. Animal research shows that blond psyllium delays and increases the absorption of metformin and ethinyl estradiol. Case reports and animal research suggest that blond psyllium might reduce absorption of lithium, digoxin, olanzapine, and carbamazepine. Finally, some pharmacokinetic studies show that psyllium does not affect the absorption of levothyroxine or warfarin. Although many of these studies evaluated blond psyllium, the fiber content in black psyllium may have similar effects.
Chitosan
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.
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.
Brand information
Manufacturer and brand details for Diet Chitosan 250 mg, from the product label.
Source Naturals
- Name
- Source Naturals, Inc.
- Street Address
- P. O. Box 2118
- City
- Santa Cruz
- State
- CA
- ZipCode
- 95062
- Web Address
- www.sourcenaturals.com
Diet Chitosan 250 mg by Source Naturals: Common Questions
Does Diet Chitosan 250 mg by Source Naturals interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Is Diet Chitosan safe if I have a shellfish allergy?
Can I take it while I'm pregnant or breastfeeding?
What side effects might I notice?
Does chitosan really help with weight loss?
Can it help my blood pressure?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if Diet Chitosan 250 mg is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind Diet Chitosan 250 mg’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Black Psyllium
Interacts with 2,025 drugsBlack psyllium is a soluble-fiber supplement made from the seeds of a Plantago plant, used mostly to ease constipation and support digestive health. It is best known and most studied for rel...
Read the full Black Psyllium monograph → Herb & supplement monographChitosan
Interacts with 3 drugsChitosan 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 & How We Checked
Diet Chitosan 250 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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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 35 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.
Black Psyllium 18 references
- McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
- Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
- Covington TR, et al. Handbook of Nonprescription Drugs. 11th ed. Washington, DC: American Pharmaceutical Association, 1996.
- Etman M. Effect of a bulk forming laxative on the bioavailablility of carbamazepine in man. Drug Dev Ind Pharm 1995;21:1901-6.
- Perlman BB. Interaction between lithium salts and ispaghula husk. Lancet 1990;335:416.
- Vaswani SK, Hamilton RG, Valentine MD, Adkinson NF. Psyllium laxative-induced anaphylaxis, asthma, and rhinitis. Allergy 1996;51:266-8. PubMed
- Lantner RR, Espiritu BR, Zumerchik P, Tobin MC. Anaphylaxis following ingestion of a psyllium-containing cereal. JAMA 1990;264:2534-6. DOI
- Kaplan MJ. Anaphylactic reaction to "Heartwise." N Engl J Med 1990;323:1072-3. DOI
- Nordstrom M, Melander A, Robertsson E, Steen B. Influence of wheat bran and of a bulk-forming ispaghula cathartic on the bioavailability of digoxin in geriatric in-patients. Drug Nutr Interact 1987;5:67-9..
- Robinson DS, Benjamin DM, McCormack JJ. Interaction of warfarin and nonsystemic gastrointestinal drugs. Clin Pharmacol Ther 1971;12:491-5. PubMed
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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.
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