Herb Safety References

How to use this document

For each herb in Grieve you want to verify, work down the **Recommended

starting points** section first, then move to specialised sources if

needed. Each source below lists:

• URL pattern — paste the herb's common name (or Latin binomial) into

the URL or use it in the site's own search box.

• What it covers — does the source mention safety at all, or just

identification?

• Authority — academic, regulatory, clinical, or community.
• Coverage of Grieve herbs — rough estimate of how many of Grieve's

1,017 herbs this source has entries for.

Recommended starting points

These three sources together cover most cases. Start here.

1. Drugs.com — Herb Database

• URL pattern: https://www.drugs.com/search.php?searchterm=<herb>

(then click "Herb" filter, or go direct via

https://www.drugs.com/npp/<herb>.html)

• What it covers: ~300 common herbs with a structured **"Safety"

/ "Pregnancy" / "Interactions" / "Side effects"** section per herb.

Each herb has a clean traffic-light style summary of evidence and

harm.

• Authority: Medical reference site used by US clinicians.
• Coverage of Grieve herbs: Medium. Major culinary/medicinal herbs

(yarrow, chamomile, foxglove, comfrey, St John's Wort) — most are

here. Less common herbs aren't.

• Notes: Fastest first check. Has a clear "Likely Safe / Possibly

Safe / Possibly Unsafe / Likely Unsafe" grading.

2. MedlinePlus — Herbs and Supplements (NIH)

• URL pattern: https://medlineplus.gov/druginfo/herb_All.html

(alphabetical list) — or

https://medlineplus.gov/search/?query=<herb>%20herb

• What it covers: ~100 major herbs, evidence-based, with explicit

"Warnings" / "Side effects" / "Interactions" sections. Includes

reliability ratings for the evidence.

• Authority: US National Library of Medicine (NIH).
• Coverage of Grieve herbs: Small-medium. Only the major ones.
• Notes: Conservative, well-cited. Read this for liability-grade

statements.

3. Plants For A Future (PFAF)

• URL pattern: https://pfaf.org/user/Plant.aspx?LatinName=<binomial>

(e.g. https://pfaf.org/user/Plant.aspx?LatinName=Digitalis+purpurea)

• What it covers: ~7,000 edible and medicinal plants, with **"Known

Hazards"** prominently listed for each species. Also notes

contraindications.

• Authority: UK-based educational charity; reviewed by botanists.
• Coverage of Grieve herbs: High. Most of Grieve's European /

North American temperate herbs are here.

• Notes: Best botanical coverage. Hazards field is concise but

reliable.

Regulatory and government sources

Authoritative; useful for legal/compliance-grade statements.

4. EMA — European Medicines Agency HMPC Monographs

• URL pattern: Browse at

https://www.ema.europa.eu/en/human-regulatory/herbal-medicicinal-products/european-union-monographs-and-list-entries

• What it covers: EU regulatory herbal assessments. Each monograph

lists traditional use, non-clinical safety data, clinical safety,

and contraindications.

• Authority: EU regulatory body.
• Coverage of Grieve herbs: Small-medium (~50 major herbs).

5. NIH Office of Dietary Supplements — Fact Sheets

• URL pattern: https://ods.od.nih.gov/factsheets/list-all/
• What it covers: Major herbs with safety, interactions, and

tolerable upper intake levels.

• Authority: NIH.
• Coverage of Grieve herbs: Small (~30 major herbs).

6. Health Canada — Natural Health Products

• URL pattern: https://www.canada.ca/en/health-canada/services/drugs-health-products/natural-non-prescription/applications-submissions/product-licensing/licensed-natural-health-products-database.html
• What it covers: Licensed natural health products in Canada, with

risk statements and warnings.

• Authority: Health Canada (regulatory).

7. TGA — Australian Therapeutic Goods Administration

• URL pattern: https://www.tga.gov.au/resources/search?f%5B0%5D=resource_search%3APublic+assessment+reports
• What it covers: Australian regulatory assessments of herbal

ingredients.

• Authority: TGA (regulatory).

Clinical and consumer references

Good for plain-language checks.

8. Mayo Clinic — Drugs & Supplements

• URL pattern: https://www.mayoclinic.org/drugs-supplements/<herb>/art-20366409
• What it covers: ~150 herbs, plain-language safety statements.
• Authority: Mayo Clinic (clinical).

9. WebMD — Herbs & Vitamins A-Z

• URL pattern: https://www.webmd.com/vitamins/ai/ingredientmono-<id>/<herb>.aspx

(search the WebMD vitamins index for the herb name)

• What it covers: Several hundred herbs with side effects,

interactions, and "When to use caution" sections.

• Authority: Medical reference site (consumer-facing).
• Notes: Good breadth but lighter on evidence grading.

10. LiverTox — NIH Liver Injury Database (Herbal section)

• URL pattern: https://www.ncbi.nlm.nih.gov/books/NBK547852/ (herbal

intro) or browse the table of contents for specific agents.

• What it covers: Drug-induced liver injury including many herbs

(kava, comfrey, germander, chaparral, etc.). Each entry has case

reports and severity grading.

• Authority: NIH / National Library of Medicine.
• Notes: Specialised for hepatotoxicity — invaluable if Grieve

claims liver-supporting use for a given herb.

Botanical and pharmacognosy references

Specialised depth for serious cross-checking.

11. NAPRALERT

• URL pattern: Subscription required (UIC, Chicago).

https://www.napralert.org/

• What it covers: Phytochemical and toxicology literature database.

Indexed literature on pharmacology, toxicology, ethnomedicine.

• Authority: University of Illinois at Chicago.
• Notes: Best academic database but subscription-based. Use via a

university library.

12. AHPA Botanical Safety Handbook

• URL pattern: Book (CRC Press); online via AHPA members.

https://www.ahpa.org/Resources/BotanicalSafetyHandbook

• What it covers: Industry-standard safety classification. Each

herb has a Class 1 / 2 / 3 / 4 safety rating and detailed notes.

• Authority: American Herbal Products Association (trade body).
• Notes: The gold-standard reference for herbal product

manufacturers.

13. HerbMed — American Botanical Council

• URL pattern: https://www.herbmed.org/ (registration required

for full access)

• What it covers: Evidence-based herbal information, peer-reviewed.

Summarises clinical trials and safety data.

• Authority: American Botanical Council.

14. Hager's Handbook (HagerROM)

• URL pattern: Springer database

https://link.springer.com/referencework/10.1007/978-3-642-16428-1

• What it covers: Pharmaceutical reference including herbal drugs;

chemical structures, pharmacology, toxicology.

• Authority: Pharmaceutical reference.
• Notes: Subscription.

Plant identification and natural product databases

Useful for taxonomic verification and cross-referencing.

15. USDA Plants Database

• URL pattern: https://plants.usda.gov/home/plantProfile?symbol=<symbol>
• What it covers: US-native plants, including some with

"Known Hazards" in the Plant Profile.

• Authority: USDA.
• Coverage of Grieve herbs: Medium for North American species.

16. POWO — Plants of the World Online (Kew Gardens)

• URL pattern: https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:<id>

or search https://powo.science.kew.org/results?q=<herb>

• What it covers: Taxonomic authority. Limited toxicity data, but

best taxonomic standard — useful for confirming the correct

Latin name before searching other sources.

• Authority: Royal Botanic Gardens, Kew.

17. Plants of the World (POWO) — toxicity annotations

• URL pattern: As above.
• What it covers: Some species records carry toxicity tags (e.g.

*Aconitum napellus*, *Digitalis purpurea*). Inconsistent — better

for taxonomy than for toxicity.

18. iNaturalist

• URL pattern: https://www.inaturalist.org/observations?verifiable=any&taxon_name=<binomial>
• What it covers: Crowdsourced photos + annotations. Community

toxicity flags exist but are not authoritative.

• Authority: Community / citizen science.
• Notes: Best for visual confirmation that you have the right

species; don't rely on its toxicity annotations.

Adverse-event reporting databases

For confirmed harm after the fact.

19. FDA Poisonous Plant Database

• URL pattern: https://www.cfsanappsexternal.fda.gov/scripts/plantox/index.cfm
• What it covers: Plants with FDA concerns — focuses on food plants

but covers medicinal herbs too.

• Authority: US FDA.

20. MHRA Yellow Card Scheme (UK)

• URL pattern: https://yellowcard.mhra.gov.uk/ (search by product

or substance)

• What it covers: UK adverse drug reaction reports, including

herbal products.

• Authority: UK Medicines and Healthcare products Regulatory Agency.

Tier-2 / less authoritative but useful for discovery

For breadth / discovery — use sparingly and cross-check before relying

on them.

21. Wikipedia — Category: Poisonous plants

• URL pattern: https://en.wikipedia.org/wiki/Category:Poisonous_plants

and subcategories.

• What it covers: Crowdsourced list of plants known to be toxic.

Useful for discovery ("did I miss that this species is poisonous?").

• Authority: Wikipedia (community).
• Notes: Variable quality — always verify against a Tier-1 source

above before quoting.

22. Practical Herbalism (and similar trade books)

• URL pattern: N/A (physical/digital book).
• What it covers: Practical herbal practice references, often

including safety notes.

• Authority: Trade book.
• Notes: Useful but not authoritative for medical claims.

23. Herbal Medicine (Ronald Hoffman, etc.)

• URL pattern: N/A (book).
• What it covers: Modern clinician-perspective references with

safety chapters.

• Authority: Clinician-authored.
• Notes: Plain-language; good for context.

24. Chinese Pharmacopoeia / TCM references

• URL pattern: N/A (book).
• What it covers: Traditional Chinese Medicine safety data, where

relevant to Grieve (some herbs overlap).

• Authority: Pharmacopoeial.
• Notes: Only useful for the small TCM overlap with Grieve.

Quick lookup workflow

For any given herb in Grieve:

1. Get the Latin binomial. Use POWO (#16) or Wikipedia to confirm.

2. Quick toxicity check. Drugs.com (#1), MedlinePlus (#2), or PFAF (#3).

3. Liver risk? Check LiverTox (#10) if the herb is taken internally.

4. Regulatory status? Check EMA (#4) or NIH ODS (#5).

5. Cross-reference with AHPA Botanical Safety Handbook (#12) if

available locally.

This covers ~90% of cases. For rare or contested herbs, escalate to

NAPRALERT (#11) or Hager's (#14).

Notes on usage for Grieve's 1931 text

• Grieve's book predates modern pharmacology. Many herbs she lists as

"harmless" or "useful" have since been reclassified. Don't take her

safety statements as authoritative.

• The strongest signal of contemporary harm is the combination of

{Drugs.com grade} + {LiverTox entry} + {EMA/HMPC monograph}.

• For "applied externally" herbs, PFAF's "Known Hazards" is usually

sufficient.

• For herbs described as useful in pregnancy, always check

MedlinePlus "Pregnancy" and LactMed (next to MedlinePlus) — Grieve's

pregnancy advice is unreliable by modern standards.

How to extend this list

If you find a useful source, add it with:

• URL pattern (with a worked example for one herb)
• What it covers
• Authority
• Coverage estimate
• Any caveats

Keep the table of contents at the top in sync.