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Dietary supplement

Reishi 500 mg Ingredients & Drug Interactions

by Nature's Answer

Reishi 500 mg label
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Capsule Category: 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 500 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

Reishi 500 mg is a dietary supplement by Nature's Answer 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 Mushroom. 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 500 mg by Nature's Answer

Ask about any prescription or over-the-counter medication and we check it for interactions with Reishi 500 mg by Nature's Answer — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Reishi 500 mg by Nature's Answer

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 Sep 10, 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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains one active ingredient: reishi mushroom at 500 mg per capsule. Reishi is a fungal supplement used in traditional medicine for a variety of purposes.

The capsule also contains inactive ingredients — vegetable cellulose (the capsule itself), rice flour, and calcium silicate — which are fillers and binders that help hold the supplement together.

Does it work?

Not established
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
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use — see Reishi Mushroom's own graded uses on its monograph.

Why this rating?
  • The label markets this product for: Supports healthy immune function.
  • We looked for evidence on: Asthma, Bronchitis, Cancer, Cancer-related fatigue, Coronavirus disease 2019 (COVID-19), Genital herpes — and 4 related terms.
  • The closest evidence on file: Reishi Mushroom is rated "Insufficient Reliable Evidence To Rate" for Bronchitis (Natural Medicines).
  • Also on file: Reishi Mushroom is rated "Insufficient Reliable Evidence To Rate" for Asthma, Lung cancer, Herpes labialis (cold sores), Cancer-related fatigue, and more.

The evidence for reishi's effectiveness is mixed and incomplete. For high cholesterol (hyperlipidemia), the data suggests it's possibly ineffective.

For other uses — including altitude sickness, Alzheimer disease, and athletic performance — we don't have enough reliable evidence in our data to rate how well it works. If you're considering reishi for a specific health goal, talk with your doctor or pharmacist about what the current evidence shows for your particular situation.

The evidence, ingredient by ingredient Reishi Mushroom

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.

Reishi mushroom is generally well tolerated in the short term, but long-term safety hasn't been well studied, so we don't know what happens with extended use. The most common side effects from taking it by mouth are dizziness, dry mouth, itching, nausea, rash, and stomach upset.

A small number of people have reported sore throat, runny nose, or respiratory allergy to reishi spores, and rare cases of insomnia and headache have been noted. There isn't enough safety data to know whether reishi is safe during pregnancy or while breastfeeding.

Talk with your doctor or pharmacist for personalized advice if you're pregnant, planning to become pregnant, or nursing.

Side effects, ingredient by ingredient Reishi Mushroom

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 — Reishi Mushroom.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications.
  • For scale: 375 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.

Before taking this product, check with your doctor or pharmacist if you take blood thinners or antiplatelet drugs, blood pressure medications, or diabetes medications. These are the three medication types documented to interact with reishi mushroom.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.

Reishi may be worth considering if you're interested in traditional mushroom supplements, but the evidence for most uses is thin or absent. If you take blood pressure medications, blood thinners, or diabetes drugs, check with your doctor or pharmacist before starting this product — the interactions are real.

Keep in mind that long-term safety data is limited, and common side effects include dizziness and nausea.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated May 19, 2022.

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 500 mg, straight from the product label.

Brand Nature's Answer
Barcode (UPC) 083000163227
Net contents 90 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD May 19, 2022
DSLD ID 264271
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Kosher, Gluten Free
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 500 mg by Nature's Answer, 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:
1 Capsule(s)
Servings per container
90
UPC/BARCODE
083000163227
IngredientAmount% DV
Reishi Mushroom500 mg--

Other ingredients: Vegetable Cellulose, Rice Flour, Calcium Silicate

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.
Brand IP Statement(s)

Discover Nature’s Answer and trust the Difference... The True Nature of Our Standards goes way beyond the herb…

Nature's Answer Since 1972

Nature's Answer Discover Nature's Answer

Copyright 2019 Nature's Answer

Precautions

Prop. 65 Warning for California Residents Warning: Consuming this product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov/food.

Warning: Keep out of reach of children.

Do not use if safety seal is damaged or missing.

If you are pregnant, nursing, taking any medications, planning any medical procedure or have a medical condition, consult with your healthcare practitioner before use.

Storage

Store in a cool, dry place.

Formula

K Parve (Kosher)

Ganoderma lucidum

Seals/Symbols

K Parve (Kosher)

Formulation

Gluten Free

Supports Healthy Immune Function

Vegan

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Suggested use: As a dietary supplement, take one (1) capsule per day, or as desired, with food or water.

FDA Disclaimer Statement

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

General Statements

For product information, call (800) 439-2324.

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

See for yourself

Reishi 500 mg by Nature's Answer label

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

Reishi 500 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 Reishi 500 mg by Nature's Answer

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

Serving size1 Capsule(s) Dosage formCapsule Servings per container90 Amounts shown are per serving.

Reishi Mushroom

Interacts with
375 drugs
500 mg 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 Mushroom monograph & interactions

Other (inactive) ingredients: Vegetable Cellulose, Rice Flour, Calcium Silicate. These complete the product’s ingredient list but are not active constituents.

Interaction report

Reishi 500 mg by Nature's Answer Drug Interactions

Want to check YOUR meds against Reishi 500 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
375Drugs
375 Moderate

Ingredients driving the most interactions

Reishi Mushroom 375

Individual Drug Interactions

The ingredients in Reishi 500 mg interact with 375 drugs. Click any drug to see the details.

1 of the 1 ingredient in Reishi 500 mg interact with drugs. Each result below shows which ingredient is responsible. Reishi Mushroom

Each ingredient & the kinds of drugs it affects

For each ingredient in Reishi 500 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.

Reishi Mushroom3 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 Mushroom full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Reishi 500 mg, from the product label.

Nature's Answer

See all Nature's Answer products
Name
Nature's Answer
Street Address
85 Commerce Drive
City
Hauppauge
State
NY
ZipCode
11788
Phone Number
(800) 439-2324
Web Address
www.naturesanswer.com
Pharmacist Counseling Corner

Reishi 500 mg by Nature's Answer: Common Questions

Does Reishi 500 mg by Nature's Answer interact with any medications?
Yes. Based on its ingredients, Reishi 500 mg 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 500 mg 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.
What is reishi mushroom, and what is it used for?
Reishi is a fungal supplement with a long history in traditional medicine. The facts on file don't specify what reishi is claimed to do, but the evidence shows it's possibly ineffective for high cholesterol and there isn't enough reliable data to rate it for altitude sickness, Alzheimer disease, or athletic performance.
Is reishi safe to take long-term?
Reishi is generally well tolerated in the short term, but long-term safety hasn't been well studied. We don't have solid data on what happens if you take it for months or years, so caution is warranted.
Can I take reishi while pregnant or breastfeeding?
There isn't enough safety data, so it's best to avoid reishi during pregnancy and while breastfeeding. Talk with your doctor or pharmacist about whether it's right for you in these situations.
What side effects might I experience?
The most common side effects are dizziness, dry mouth, itching, nausea, rash, and stomach upset. A small number of people have reported sore throat, runny nose, or allergy to reishi spores, and rare cases of insomnia and headache.
Why does reishi interact with so many medications?
Reishi doesn't interact with 375 different drugs — that's the deduplicated total of individual medications affected by all the product's ingredients combined. The interactions occur because reishi has effects on blood pressure, blood clotting, and blood sugar, which overlap with how certain drug classes work.

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

Not sure if Reishi 500 mg is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

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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.

Reishi 500 mg label
Go deeper

The Full Monographs Behind Reishi 500 mg’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 500 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.

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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