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Dietary supplement

Reishi Ingredients & Drug Interactions

by Host Defense Mushrooms

Reishi label
See full label image
Capsule Category: Non-nutrient/non-botanical
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 Reishi 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

Reishi is a dietary supplement by Host Defense Mushrooms with 1 active ingredient. Its ingredients are commonly taken for immune support, fatigue and general well-being, stress and sleep.Based on those ingredients, 375 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Reishi. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Reishi by Host Defense Mushrooms

Ask about any prescription or over-the-counter medication and we check it for interactions with Reishi by Host Defense Mushrooms — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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Computed from our clinical databases

HelloPharmacist Scorecard of Reishi by Host Defense Mushrooms

Four independent checks of what is known — a summary of the available information, not a grade of the product itself.

Evidence for Intended Use
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
Not assessable

None of the active ingredients could be matched to our evidence database, so intended use can't be graded.

Why this rating?
  • None of the active ingredients could be matched to a HelloPharmacist monograph, so intended use can't be graded against our evidence data.
Ingredient Transparency
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 2 of its 2 active ingredients.
  • “Reishi” is listed as a grouped ingredient — the label gives one combined amount (1 Gram(s)) without saying how much of each component you get.
Known Interaction Concern
Not assessable

None of the active ingredients could be matched to our interaction database.

Why this rating?
  • We couldn't match any ingredient to a HelloPharmacist monograph, so there was nothing to check interactions against.
Safety Information
Unable to assess

None of the active ingredients could be matched to our safety data.

Why this rating?
  • We couldn't match any ingredient to a HelloPharmacist monograph, so there was no safety data to measure.

HelloPharmacist summaryFully disclosed formula with no assessable stated purpose. Medication interactions could not be assessed, and safety information could not be assessed.

Assessment coverage: 0 of 2 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 24, 2021.

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 Reishi, straight from the product label.

Brand Host Defense Mushrooms
Net contents 120 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Sep 24, 2021
DSLD ID 255169
Product type Non-nutrient/non-botanical
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Organic
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 Reishi by Host Defense Mushrooms, 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:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
60
IngredientAmount% DV
Polysaccharides550 mg--
Fatty Acids5 mg--
Reishi1 Gram(s)--

Other ingredients: dried myceliated Brown Rice, Pullulan

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.
General Statements

Host Defense is the #1 Best-Selling Mushroom Brand in the U.S.: The highest quality and scientifically validated

From the Forest, to our Farm, to You

Source: SPINSscan Natural/Natural Products Supermarkets > $2MM/Total US - Natural Channel/Mushrooms Ingredient Report/52 Wks Ending 3/20/2016

Formulation

Guaranteed, accurate identity of each mushroom Heat treated to proper temperature to ensure safety & bioavailability U.S. grown and processed Produced under the direct supervision of Paul Stamets, D.Sc. Proceeds help to save bees, trees, people & planet

Identity Guaranteed

Made with certified organic ingredients

Non GMO Project Verified Nongmoproject.org

Non-GMO verified ingredients

Bee Friendly

Made with U.S. grown organic mushrooms

Supports a healthy heart

Gluten free

Host Defense Reishi This popular species, used for more than two millennia in Asia, has been respectfully called the "Mushroom of Immortality". Reishi grows throughout the world and is found primarily on hardwood trees. This mushroom is well known as a tonic for supporting general wellness and vitality.

Certified Organic by the Washington State Department of Agriculture.

Seals/Symbols

Producer Certified Organic Washington State Dept. of Agriculture

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Directions for use: As a dietary supplement, take 2 capsules once per day. Can be taken with food or without, on an empty stomach or as recommended by your healthcare advisor.

Precautions

Consult your healthcare advisor regarding the use of this product during pregnancy.

Keep out of reach of children.

Formula

Host Defense Reishi uses activated, optimally dried, Certified Organic mushroom mycelium, with a full spectrum of constituents: >55% (550mg/serving) polysaccharides, .5% (5mg/serving) fatty acids, and an array of extracellular constituents, including enzymes, antioxidants, and prebiotics for the microbiome, essential for Supporting Natural Immunity.

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.

See for yourself

Reishi by Host Defense Mushrooms label

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

Reishi 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 Reishi by Host Defense Mushrooms

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Reishi

Interacts with
375 drugs
1 Gram(s) per serving

Reishi is a traditional Asian mushroom widely used to support the immune system and overall wellness. Human evidence for most of its claimed benefits...

Reishi monograph & interactions
  • › Polysaccharides
  • › Fatty Acids

Other (inactive) ingredients: Dried myceliated Brown Rice, Pullulan. These complete the product’s ingredient list but are not active constituents.

Interaction report

Reishi by Host Defense Mushrooms Drug Interactions

Reishi contains a single active ingredient, and it has known interactions with 375 medications. Here’s the picture, then you can look up your own drug.

Want to check YOUR meds against Reishi?

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
375Drugs
375 Moderate

Ingredients driving the most interactions

Reishi 375

Individual Drug Interactions

The ingredients in Reishi interact with 375 drugs. Click any drug to see the details.

1 of the 1 ingredient in Reishi interact with drugs. Each result below shows which ingredient is responsible. Reishi

Each ingredient & the kinds of drugs it affects

For each ingredient in Reishi 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.

Reishi3 drug types · 375 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, high doses of reishi mushroom might increase the risk of bleeding.
A dose of 1.5 grams daily of reishi mushroom does not seem to decrease platelet aggregation, but a higher dose of 3 grams daily does.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, reishi mushroom might have additive effects with antidiabetes drugs.
Animal research suggests that reishi mushroom decreases blood sugar. However, in patients with type 2 diabetes, taking reishi mushroom does not reduce fasting glucose levels, and its effects on glycated hemoglobin are inconsistent.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, concurrent use of reishi mushroom with antihypertensive drugs might increase the risk of hypotension.
Reishi mushroom has shown hypotensive activity in animal research. Clinical evidence suggests that reishi mushroom reduces blood pressure in some, but not all, patients with hypertension.

Likelihood Possible Evidence D
Reishi full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Reishi, from the product label.

Host Defense Mushrooms

See all Host Defense Mushrooms products
Name
Fungi Perfecti, LLC
Street Address
PO Box 7634
City
Olympia
State
WA
ZipCode
98507
Phone Number
877-504-6926
Web Address
Hostdefense.com
Pharmacist Counseling Corner

Reishi by Host Defense Mushrooms: Common Questions

Does Reishi by Host Defense Mushrooms interact with any medications?
Yes. Based on its ingredients, Reishi has a known interaction with 375 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Reishi contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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.

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

Not sure if Reishi is safe with your meds?

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Ask a pharmacist

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.

Reishi label
Go deeper

The Full Monographs Behind Reishi’s Ingredients

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

Herb & supplement monograph

Reishi Mushroom

Interacts with 375 drugs

Reishi is a traditional Asian mushroom widely used to support the immune system and overall wellness. Human evidence for most of its claimed benefits is limited or low-quality, so it should...

Read the full Reishi Mushroom monograph →
Sources

Sources & How We Checked

Reishi'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.

Reishi Mushroom 17 references
  1. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  2. Tao J, Feng KY. Experimental and clinical studies on inhibitory effect of ganoderma lucidum on platelet aggregation. J Tongji Med Univ 1990;10:240-3. PubMed
  3. Singh AB, Gupta SK, Pereira BM, Prakash D. Sensitization to Ganoderma lucidum in patients with respiratory allergy in India. Clin Exp Allergy 1995;25:440-7.
  4. Lee SY, Rhee HM. Cardiovascular effects of mycelium extract of Ganoderma lucidum: inhibition of sympathetic outflow as a mechanism of its hypotensive action. Chem Pharm Bull (Tokyo) 1990;38:1359-64. PubMed
  5. Kwok Y, Ng KFJ, Li, CCF, et al. A prospective, randomized, double-blind, placebo-controlled study of the platelet and global hemostatic effects of Ganoderma lucidum (Ling-Zhi) in healthy volunteers. Anesth Analg 2005;101:423-6. PubMed
  6. Wanmuang, H., Leopairut, J., Kositchaiwat, C., Wananukul, W., and Bunyaratvej, S. Fatal fulminant hepatitis associated with Ganoderma lucidum (Lingzhi) mushroom powder. J Med Assoc Thai. 2007;90(1):179-181.
  7. Seto, S. W., Lam, T. Y., Tam, H. L., Au, A. L., Chan, S. W., Wu, J. H., Yu, P. H., Leung, G. P., Ngai, S. M., Yeung, J. H., Leung, P. S., Lee, S. M., and Kwan, Y. W. Novel hypoglycemic effects of Ganoderma lucidum water-extract in obese/diabetic (+db/+db
  8. Chu, T. T., Benzie, I. F., Lam, C. W., Fok, B. S., Lee, K. K., and Tomlinson, B. Study of potential cardioprotective effects of Ganoderma lucidum (Lingzhi): results of a controlled human intervention trial. Br.J.Nutr. 2012;107(7):1017-1027.
  9. Jin, X., Ruiz, Beguerie J., Sze, D. M., and Chan, G. C. Ganoderma lucidum (Reishi mushroom) for cancer treatment. Cochrane.Database.Syst.Rev. 2012;6:CD007731.
  10. Kabir, Y., Kimura, S., and Tamura, T. Dietary effect of Ganoderma lucidum mushroom on blood pressure and lipid levels in spontaneously hypertensive rats (SHR). J Nutr Sci Vitaminol.(Tokyo) 1988;34(4):433-438. PubMed
  11. Kanmatsuse, K., Kajiwara, N., Hayashi, K., Shimogaichi, S., Fukinbara, I., Ishikawa, H., and Tamura, T. [Studies on Ganoderma lucidum. I. Efficacy against hypertension and side effects]. Yakugaku Zasshi 1985;105(10):942-947. PubMed
  12. Gao, Y., Lan, J., Dai, X., Ye, J., and Zhou, S. A Phase I/II Study of Ling Zhi Mushroom Ganoderma lucidum(W.Curt: Fr.) Lloyd (Aphyllophoromycetideae) Extract in Patients with Type II Diabetes Mellitus. International Journal of Medicinal Mushrooms 2004;6. DOI
  13. Jin H, Zhang G, Cao X, and et al. Treatment of hypertension by linzhi combined with hypotensor and its effects on arterial, arteriolar and capillary pressure and microcirculation. In: Niimi H, Xiu RJ, Sawada T, and et al. Microcirculatory Approach to Asi
  14. Klupp NL, Chang D, Hawke F, Kiat H, Cao H, Grant SJ, Bensoussan A. Ganoderma lucidum mushroom for the treatment of cardiovascular risk factors. Cochrane Database Syst Rev. 2015 Feb 17;2:CD007259. PubMed
  15. Zhao H, Zhang Q, Zhao L, Huang X, Wang J, Kang X. Spore Powder of Ganoderma lucidum Improves Cancer-Related Fatigue in Breast Cancer Patients Undergoing Endocrine Therapy: A Pilot Clinical Trial. Evid Based Complement Alternat Med. 2012;2012:809614.
  16. Pazzi F, Adsuar JC, Domínguez-Muñoz FJ, García-Gordillo MA, Gusi N, Collado-Mateo D. Ganoderma lucidum effects on mood and health-related quality of life in women with fibromyalgia. Healthcare (Basel) 2020;8(4):520. PubMed
  17. Kogure T, Koiwai A, Fukushi D, et al. Hypereosinophilia with hepatic nodule formation caused by Ganoderma lucidum. Intern Med 2021;60(24):3897-3903.

See these in context on the Reishi Mushroom 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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