Major interaction on record — check this product against your medications before combining. Based on 6 of 7 ingredients. Check your meds →
Dietary supplement

Hair, Skin & Nail Support Ingredients & Drug Interactions

by Gaia Herbs

Hair, Skin & Nail Support label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Hair, Skin & Nail Support 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: Major

Hair, Skin & Nail Support is a dietary supplement by Gaia Herbs with 7 active ingredients. Its ingredients are commonly taken for enlarged prostate (bph) symptoms, seasonal allergies, joint pain and arthritis.Based on those ingredients, 1,389 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Astaxanthin, Alfalfa Leaf Extract, Gotu Kola leaf extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Hair, Skin & Nail Support by Gaia Herbs

Ask about any prescription or over-the-counter medication and we check it for interactions with Hair, Skin & Nail Support by Gaia Herbs — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Hair, Skin & Nail Support by Gaia Herbs

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 Aug 6, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

Most active ingredients don't disclose an individual amount — you can't tell how much of each you're getting.

Why this rating?
  • The label discloses an exact amount for 0 of its 7 active ingredients.
  • “Proprietary Extract Blend” is a proprietary blend — the label gives one combined amount (1,240 mg) without saying how much of each component you get.

This product contains 7 active ingredients: stinging nettle leaf extract, gotu kola leaf extract, burdock root extract, horsetail extract, a proprietary extract blend, astaxanthin, and alfalfa leaf extract. Each plays a traditional role in skin, hair, and nail health formulations.

The capsule itself is made from vegetable glycerin and a vegan capsule material, with water as an inactive ingredient.

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: Hair, skin and nail health support.
  • We looked for evidence on: Acne, Aging skin, Atopic dermatitis (eczema), Dry skin, Androgenic alopecia, Scarring — and 4 related terms.
  • The strongest evidence on file: Gotu Kola is rated "Possibly Effective" for Burns (Natural Medicines).
  • Also on file: Burdock is rated "Insufficient Reliable Evidence To Rate" for Acne, Aging skin, Atopic dermatitis (eczema), Dry skin.
  • Also on file: Gotu Kola is rated "Insufficient Reliable Evidence To Rate" for Aging skin, Atopic dermatitis (eczema).

The evidence for what this product actually does is sparse. Stinging nettle is possibly effective for diabetes, but the other uses listed—allergic rhinitis, anemia, asthma, benign prostatic hyperplasia, and gingivitis—have insufficient evidence.

Gotu kola is possibly effective for venous insufficiency and burns, but possibly ineffective for cognitive function and radiation dermatitis, with insufficient evidence for Alzheimer's and anxiety. Burdock, horsetail, astaxanthin, and alfalfa all lack sufficient reliable evidence for their claimed uses—acne, aging skin, cancer, eczema, urinary incontinence, cognitive decline, and others.

In short, we have limited data showing this formula works for hair, skin, and nail support specifically.

The evidence, ingredient by ingredient Stinging Nettle Gotu Kola Burdock Horsetail Astaxanthin Alfalfa

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 6 of the 6 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 6 of 6.
  • General safety write-ups exist for 6 of 6.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Stinging nettle and gotu kola are generally well tolerated short-term but carry warnings about liver concerns in rare cases; common side effects include constipation, diarrhea, or nausea. Horsetail may cause abdominal bloating, increased bowel movements, and nausea, and crude forms contain thiaminase, which can cause thiamine deficiency with long-term use.

Burdock is well tolerated as a food but allergic reactions including anaphylaxis have been reported rarely. Astaxanthin is generally well tolerated; at higher doses, abdominal pain and color changes in stool have occurred.

Alfalfa may cause abdominal discomfort, diarrhea, and flatulence, and a lupus-like syndrome has been reported rarely after chronic use. Pregnancy: stinging nettle is likely unsafe; gotu kola is possibly safe; burdock, horsetail, astaxanthin, and alfalfa all lack enough safety data, so avoid medicinal amounts.

Breastfeeding: stinging nettle, horsetail, astaxanthin, and alfalfa all lack safety data; gotu kola's lactation safety is unknown but best avoided; no data on file for burdock.

Side effects, ingredient by ingredient Stinging Nettle Gotu Kola Burdock Horsetail Astaxanthin Alfalfa

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 6 of the 6 matched ingredients can interact with medications — Alfalfa, Burdock, Stinging Nettle, Gotu Kola, Horsetail, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; lithium.
  • For scale: 1,390 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 or other blood thinners (Major interaction with alfalfa), antidiabetes drugs, diuretics, lithium, HIV antiretroviral drugs (especially efavirenz), central nervous system depressants, drugs that make you sensitive to sunlight, hormonal contraceptives, estrogen therapy, immunosuppressants, or any drug that depends on liver enzymes CYP3A4 or CYP2B6 to be broken down.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with some supporting evidence for its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

This is a multi-ingredient supplement with limited evidence for hair, skin, and nail support. It's generally well tolerated short-term by healthy adults, but if you take blood thinners, antidiabetes drugs, HIV medications, diuretics, lithium, immunosuppressants, hormonal contraceptives, or estrogen therapy, you need to check your exact medications with the tool on this page before starting.

Talk with your own doctor or pharmacist before taking this product, especially if you're pregnant, breastfeeding, or managing a chronic condition.

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

Assessment coverage: 6 of 7 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 21, 2023.

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 Hair, Skin & Nail Support, straight from the product label.

Brand Gaia Herbs
Net contents 60 Vegan Liquid Phyto-Cap(s)(R)
Market status On market
Date entered into DSLD Apr 21, 2023
DSLD ID 272275
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Women (not pregnant or lactating), 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 Hair, Skin & Nail Support by Gaia Herbs, 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
30
IngredientAmount% DV
Calories5 Calorie(s)--
Total Carbohydrates2 Gram(s)1%
Stinging Nettle leaf extract0 NP--
Gotu Kola leaf extract0 NP--
Burdock root extract0 NP--
Horsetail extract0 NP--
Proprietary Extract Blend1240 mg--
Astaxanthin0 NP--
Triphala Extract0 NP--
Alfalfa Leaf Extract0 NP--

Other ingredients: Vegetable Glycerin, vegan Capsule, Water

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.
Formulation

New look same formula

Beauty & radiance support Traditionally for supporting healthy growth & radiance

Natural separation may occur. This does not affect product quality.

Vegan

Gluten-free Soy-free

Formula

With horsetail, gotu kola & gaia-grown nettle

Each 2 capsules contain 3,350 mg dry herb equivalent.

FDA Statement of Identity

Herbal Supplement

Suggested/Recommended/Usage/Directions

Suggested Use Adults take 2 capsules 2 times daily between meals.

Precautions

Not for use during pregnancy or lactation. If you have a medical condition or take medications, please consult with your doctor before use.

Store away from children.

Use only as directed on label. Safety-sealed for your protection.

Storage

Keep bottle capped at all times and store in a cool, dry place.

General Statements

Meetyourherbs.com Gaia Herbs delivers unprecedented traceability by screening every product and sharing the results online. See for yourself, and learn more about your herbs, by entering the unique ID # below at meetyourherbs.com

Gaia Farm, Brevard NC Purity - Keep it clean All products are screened for pesticides, microbes & heavy metals. Integrity - Keep it real See the proof at meetyourherbs.com, the world's first herb traceability platform. Potency - Keep it strong Concentrated plant extracts are delivered in our patented Phyto-Caps technology. Discover our guiding truths at: Facebook Instagram @gaiaherbs

Seals/Symbols

EST 1987 USA Integrity Purity Potency Certified B Corporation

Brand IP Statement(s)

Gaia Herbs Connecting plants & people since 1987

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

Hair, Skin & Nail Support by Gaia Herbs label

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

Hair, Skin & Nail Support 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 Hair, Skin & Nail Support by Gaia Herbs

These are the 7 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 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.

Proprietary Extract Blend

1240 mg per serving

Other (inactive) ingredients: Vegetable Glycerin, Vegan Capsule, Water. These complete the product’s ingredient list but are not active constituents.

Interaction report

Hair, Skin & Nail Support by Gaia Herbs Drug Interactions

Want to check YOUR meds against Hair, Skin & Nail Support?

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
1,389Drugs
2 Major 1,387 Moderate

Ingredients driving the most interactions

Astaxanthin 671
Alfalfa Leaf Extract 583
Gotu Kola leaf extract 579
Horsetail extract 188
Stinging Nettle leaf extract 164

Individual Drug Interactions

The ingredients in Hair, Skin & Nail Support interact with 1,389 drugs. Click any drug to see the details.

6 of the 7 ingredients in Hair, Skin & Nail Support interact with drugs. Each result below shows which ingredient is responsible. Astaxanthin Alfalfa Leaf Extract Gotu Kola leaf extract Horsetail extract Stinging Nettle leaf extract Burdock root extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Hair, Skin & Nail Support 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.

Astaxanthin2 drug types · 671 drugs

Cytochrome P450 2B6 (Cyp2B6) Substrates

Theoretically, astaxanthin may decrease levels of drugs metabolized by CYP2B6.
In vitro research shows that astaxanthin induces cytochrome CYP2B6 enzyme activity in human hepatocytes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 3A4 (Cyp3A4) Substrates

Theoretically, astaxanthin may decrease levels of drugs metabolized by CYP3A4.
In vitro research shows that astaxanthin induces CYP3A4 enzyme activity in human hepatocytes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Astaxanthin full monograph & interactions

Alfalfa Leaf Extract6 drug types · 583 drugs

Warfarin (Coumadin)

Theoretically, alfalfa might reduce the anticoagulant activity of warfarin.
Alfalfa contains a large amount of vitamin K. This could theoretically interfere with the activity of warfarin.

Likelihood Probable Evidence D
Antidiabetes Drugs

Theoretically, alfalfa might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research suggests that alfalfa decreases blood sugar in diabetic mice. Also, in one case report, a diabetic patient experienced hypoglycemia after consuming alfalfa extract. Monitor blood glucose levels closely. Dose adjustments might be necessary.

Likelihood Possible Evidence D
Contraceptive Drugs

Theoretically, alfalfa might interfere with the activity of contraceptive drugs.
Alfalfa contains coumestrol, a phytoestrogen, and isoflavonoids, which have estrogenic effects.

Likelihood Possible Evidence D
Estrogens

Theoretically, alfalfa might interfere with hormone therapy.
Alfalfa contains coumestrol, a phytoestrogen, and isoflavonoids, which have estrogenic effects.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, alfalfa might decrease the efficacy of immunosuppressive therapy.
In vitro research and human case reports suggest that alfalfa may have immunostimulant effects.

Likelihood Possible Evidence D
Photosensitizing Drugs

Theoretically, concomitant use of alfalfa with photosensitizing drugs might have additive effects.
Animal research suggests that excessive doses of alfalfa may increase photosensitivity, possibly due to its chlorophyll content. It is unclear if this effect would be clinically relevant in humans.

Likelihood Possible Evidence D
Alfalfa Leaf Extract full monograph & interactions

Gotu Kola leaf extract2 drug types · 579 drugs

Cns Depressants

Theoretically, taking gotu kola might increase the sedative effects of CNS depressants.
In vitro research suggests that gotu kola may have sedative effects via binding of GABA receptors.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, taking gotu kola with hepatotoxic drugs might have additive adverse effects.
There are at least four case reports of hepatotoxicity associated with the use of gotu kola. However, more information is needed to determine if gotu kola was the causative factor in these cases.

Likelihood Possible Evidence D
Gotu Kola leaf extract full monograph & interactions

Horsetail extract5 drug types · 188 drugs

Antidiabetes Drugs

Theoretically, taking horsetail with antidiabetes drugs might increase the risk of hypoglycemia.
Equisetum myriochaetum has demonstrated hypoglycemic activity in clinical research. In an animal diabetic model, Equisetum giganteum had hypoglycemic effects. It is unclear whether other horsetail species have hypoglycemic effects.

Likelihood Possible Evidence D
Diuretic Drugs

Theoretically, taking horsetail with diuretic drugs might increase potassium loss and the risk of hypokalemia.
Laboratory research shows that various species of horsetail have diuretic properties. Due to its diuretic effects, there has been concern that taking horsetail along with potassium-depleting diuretics might increase the risk for hypokalemia. However, pharmacokinetic research in humans shows that taking horsetail 900 mg daily for 4 days does not affect urinary excretion of electrolytes, including potassium and sodium, despite having a diuretic effect similar to taking hydrochlorothiazide 25 mg daily. It is unclear if taking horsetail for a longer duration would affect electrolyte levels. Until more is known, use with caution.

Likelihood Possible Evidence D
Efavirenz (Sustiva)

Theoretically, horsetail might decrease the levels and clinical effects of efavirenz.
In two case reports, patients were found to have detectable viral loads when taking horsetail-containing supplements along with an antiretroviral regimen that included efavirenz. In one case, the antiretroviral regimen included zidovudine, lamivudine, and efavirenz; in the other case, the regimen consisted of emtricitabine, tenofovir disoproxil fumarate, and efavirenz. One month after discontinuing horsetail, the viral loads became undetectable in both cases. The exact mechanism of this interaction is unknown. It is also unclear if this interaction is specific to efavirenz or if it is related to various components of antiretroviral therapy.

Likelihood Possible Evidence D
Lithium

Theoretically, horsetail might increase the levels and adverse effects of lithium.
Animal research suggests that horsetail has diuretic properties. Theoretically, due to these potential diuretic effects, horsetail might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Possible Evidence D
Nucleoside Reverse Transcriptase Inhibitors (Nrtis)

Theoretically, horsetail might decrease the levels and clinical effects of NRTIs.
In two case reports, patients were found to have detectable viral loads when taking horsetail-containing supplements along with an antiretroviral therapy. In one case, the antiretroviral regimen included zidovudine, lamivudine, and efavirenz; in the other case, the regimen consisted of emtricitabine, tenofovir disoproxil fumarate, and efavirenz. One month after discontinuing the supplement, the viral loads became undetectable in both cases. The exact mechanism of these interactions is unknown. It is also unclear if these interactions are specific to NRTIs or if they are related to various components of antiretroviral therapy.

Likelihood Possible Evidence D
Horsetail extract full monograph & interactions

Stinging Nettle leaf extract4 drug types · 164 drugs

Antidiabetes Drugs

Theoretically, stinging nettle might have additive effects with antidiabetes drugs.
Clinical research shows that stinging nettle might decrease blood glucose levels in patients with diabetes.

Likelihood Possible Evidence B
Diuretic Drugs

Theoretically, combining stinging nettle with diuretic drugs may have additive effects.
Animal research suggests that the above ground parts and roots of stinging nettle may have a diuretic effect.

Likelihood Possible Evidence D
Lithium

Theoretically, stinging nettle might reduce excretion and increase levels of lithium.
Animal research suggests that stinging nettle has diuretic and natriuretic properties, which could alter the excretion of lithium. The dose of lithium might need to be decreased.

Likelihood Possible Evidence D
Warfarin (Coumadin)

There is some concern that stinging nettle might decrease the effects of anticoagulant drugs such as warfarin.
Stinging nettle contains a significant amount of vitamin K. When taken in large quantities, this might interfere with the activity of warfarin.

Likelihood Possible Evidence D
Stinging Nettle leaf extract full monograph & interactions

Burdock root extract1 drug type · 122 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, taking burdock with anticoagulant or antiplatelet drugs might increase the risk of bleeding.

In vitro research shows that lignans from burdock reduce rabbit platelet aggregation by inhibiting platelet activating factor. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Burdock root extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Hair, Skin & Nail Support, from the product label.

Gaia Herbs

See all Gaia Herbs products
Name
Gaia Herbs, Inc.
Street Address
101 Gaia Herbs Dr.
City
Brevard
State
NC
ZipCode
28712
Web Address
GaiaHerbs.com
Pharmacist Counseling Corner

Hair, Skin & Nail Support by Gaia Herbs: Common Questions

Does Hair, Skin & Nail Support by Gaia Herbs interact with any medications?
Yes. Based on its ingredients, Hair, Skin & Nail Support has a known interaction with 1,389 medications, including 2 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Hair, Skin & Nail Support contains 7 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.
Is this safe to take while pregnant?
No. Stinging nettle is likely unsafe in pregnancy. Gotu kola is possibly safe, but burdock, horsetail, astaxanthin, and alfalfa all lack enough safety data, so medicinal amounts should be avoided. Talk with your doctor before taking any supplement during pregnancy.
Can I take this while breastfeeding?
The safety data aren't there. Stinging nettle, horsetail, astaxanthin, and alfalfa should all be avoided while breastfeeding due to insufficient safety information. Gotu kola's lactation safety is unknown. Check with your doctor or pharmacist for personalized advice.
What are the most common side effects?
The most common are digestive—constipation, diarrhea, nausea, abdominal discomfort, and flatulence. Astaxanthin at higher doses can cause abdominal pain and color changes in stool. These are usually mild, but if they persist or worsen, stop taking it and talk with your pharmacist.
Does this actually work for hair, skin, and nails?
The evidence is limited. Stinging nettle is possibly effective for diabetes, and gotu kola is possibly effective for venous insufficiency and burns, but we don't have solid evidence that the ingredients in this formula work specifically for hair, skin, and nail health.
What is astaxanthin, and why is it in here?
Astaxanthin is a red pigment from algae and seafood, often used in anti-aging formulas because of its antioxidant reputation. In this product, it's meant to support skin health, though the reliable evidence for that specific use is insufficient.
Can horsetail cause any serious problems?
Crude horsetail contains thiaminase, which can deplete thiamine (vitamin B1) with prolonged use. This is rare but serious. Canadian products are required to be thiaminase-free, so check the label. Also, horsetail may dangerously interact with HIV medications and blood sugar drugs, so check with your doctor first if you use either.

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

Not sure if Hair, Skin & Nail Support 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.

Hair, Skin & Nail Support label
Go deeper

The Full Monographs Behind Hair, Skin & Nail Support’s Ingredients

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

Herb & supplement monograph

Stinging Nettle

Interacts with 164 drugs

Stinging nettle is a common plant used as food and in traditional medicine, most often for prostate symptoms, allergies, and joint pain. The evidence is mixed and mostly preliminary, so it i...

Read the full Stinging Nettle monograph → Herb & supplement monograph

Gotu Kola

Interacts with 579 drugs

Gotu kola is a traditional Ayurvedic and Asian herb that people use for wound healing, circulation, skin problems, and as a calming or memory-supporting herb. Some early studies suggest poss...

Read the full Gotu Kola monograph → Herb & supplement monograph

Burdock

Interacts with 122 drugs

Burdock is a traditional herb most often used for skin problems and as a so-called 'blood purifier,' but high-quality human studies are lacking and most claims are not well proven. It is wid...

Read the full Burdock monograph → Herb & supplement monograph

Horsetail

Interacts with 188 drugs

Horsetail is a traditional herb most often used as a mild diuretic and for hair, nail, and bone support, but high-quality human evidence is limited. It can cause thiamine (vitamin B1) loss w...

Read the full Horsetail monograph → Herb & supplement monograph

Astaxanthin

Interacts with 671 drugs

Astaxanthin is a reddish carotenoid pigment with strong antioxidant activity in the lab, and it is widely promoted for skin, eye, heart, and exercise benefits. Early human studies are promis...

Read the full Astaxanthin monograph → Herb & supplement monograph

Alfalfa

Interacts with 583 drugs

Alfalfa is a nutrient-rich legume that people use for high cholesterol, menopause symptoms, and general wellness, but solid human evidence for most of these uses is limited. It is best avoid...

Read the full Alfalfa monograph →
Sources

Sources & How We Checked

Hair, Skin & Nail Support'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 101 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.

Stinging Nettle 23 references
  1. Monographs on the medicinal uses of plant drugs. Exeter, UK: European Scientific Co-op Phytother, 1997.
  2. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  3. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  4. Schulz V, Hansel R, Tyler VE. Rational Phytotherapy: A Physician's Guide to Herbal Medicine. Terry C. Telger, transl. 3rd ed. Berlin, GER: Springer, 1998.
  5. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  6. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  7. Mittman P. Randomized, double-blind study of freeze-dried Urtica dioica in the treatment of allergic rhinitis. Planta Med 1990;56:44-7.
  8. Vontobel HP, Herzog R, Rutishauser G, Kres H. [Results of a double-blind study on the effectiveness of ERU (extractum radicis Urticae) capsules in conservative treatment of benign prostatic hyperplasia]. (Abstract). Urologe A 1985;24:49-51.
  9. Randall C, Randall H, Dobbs F, et al. Randomized controlled trial of nettle sting for treatment of base-of-thumb pain. J R Soc Med 2000;93:305-9. PubMed
  10. Caliskaner Z, Karaayvaz M, Ozturk S. Misuse of a herb: stinging nettle (Urtica urens) induced severe tongue oedema. Complement Ther Med 2004;12:57-8. PubMed
  11. Krzeski, T., Kazon, M., Borkowski, A., Witeska, A., and Kuczera, J. Combined extracts of Urtica dioica and Pygeum africanum in the treatment of benign prostatic hyperplasia: double-blind comparison of two doses. Clin Ther 1993;15(6):1011-1020.
  12. Randall, C., Meethan, K., Randall, H., and Dobbs, F. Nettle sting of Urtica dioica for joint pain--an exploratory study of this complementary therapy. Complement Ther Med 1999;7(3):126-131. PubMed
  13. Tahri, A., Yamani, S., Legssyer, A., Aziz, M., Mekhfi, H., Bnouham, M., and Ziyyat, A. Acute diuretic, natriuretic and hypotensive effects of a continuous perfusion of aqueous extract of Urtica dioica in the rat. J Ethnopharmacol 2000;73(1-2):95-100. PubMed
  14. Sahin, M., Yilmaz, H., Gursoy, A., Demirel, A. N., Tutuncu, N. B., and Guvener, N. D. Gynaecomastia in a man and hyperoestrogenism in a woman due to ingestion of nettle (Urtica dioica). N.Z.Med.J. 2007;120(1265):U2803.
  15. Randall, C., Dickens, A., White, A., Sanders, H., Fox, M., and Campbell, J. Nettle sting for chronic knee pain: a randomised controlled pilot study. Complement Ther.Med. 2008;16(2):66-72. PubMed
  16. Rayburn, K., Fleischbein, E., Song, J., Allen, B., Kundert, M., Leiter, C., and Bush, T. Stinging nettle cream for osteoarthritis. Altern.Ther.Health Med. 2009;15(4):60-61.
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Gotu Kola 18 references
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Burdock 11 references
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Horsetail 14 references
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Astaxanthin 3 references
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Alfalfa 32 references
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