Interactions on record — worth a quick check against your medications. Based on 4 of 5 ingredients. Check your meds →
Dietary supplement

N-W Ingredients & Drug Interactions

by Pure Herbs

N-W label
See full label image
Liquid 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 N-W 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

N-W is a dietary supplement by Pure Herbs with 5 active ingredients. Its ingredients are commonly taken for asthma and breathing problems, cough and bronchitis, smoking cessation aid.Based on those ingredients, 930 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Valerian root extract, Hops flower extract, Skullcap aerial parts extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against N-W by Pure Herbs

Ask about any prescription or over-the-counter medication and we check it for interactions with N-W by Pure Herbs — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of N-W by Pure 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 27, 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 5 active ingredients.
  • “Proprietary Blend” is a proprietary blend — the label gives one combined amount (1,874 mg) without saying how much of each component you get.

Pure Herbs N-W is a liquid containing five active ingredients in a proprietary blend. Lobelia aerial parts extract, blue vervain aerial parts extract, skullcap aerial parts extract, hops flower extract, and valerian root extract make up the formula.

There are no other inactive ingredients listed.

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: nervous system support and calmness.
  • We looked for evidence on: Anxiety, Stress, Insomnia, Pre-procedural anxiety, nervousness, tension — and 1 related terms.
  • The strongest evidence on file: Valerian is rated "Possibly Effective" for Insomnia (Natural Medicines).
  • Also on file: Hops is rated "Insufficient Reliable Evidence To Rate" for Anxiety, Insomnia.
  • Also on file: Valerian is rated "Insufficient Reliable Evidence To Rate" for Pre-procedural anxiety, Tension headache, Stress.

The evidence for what this blend does is limited. Valerian root shows possibly effective evidence for insomnia — some trial data backs its use for sleep.

For the other ingredients and uses, the facts show insufficient reliable evidence to rate them, meaning we don't have solid trial data to say whether they work. Lobelia is rated possibly ineffective for smoking cessation.

The evidence, ingredient by ingredient Lobelia Skullcap Hops Valerian

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 4 of the 4 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 4 of 4.
  • General safety write-ups exist for 4 of 4.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

These ingredients are generally well tolerated short-term, but lobelia carries a caution: it can be toxic and cause serious effects at higher doses — symptoms include sweating, fast heartbeat, tremors, and in severe cases, coma or death. Nausea, vomiting, diarrhea, dizziness, and throat irritation are possible with any dose, even as low as 50 mg.

Skullcap and hops may cause drowsiness, cognitive impairment, and mild digestive upset. Valerian can cause dizziness, drowsiness, mental slowness, headache, and vivid dreams; if you take it long-term and stop abruptly, withdrawal symptoms like agitation and insomnia may occur — taper slowly instead.

Rare reports link valerian-containing products to liver injury, though most cases involved multi-ingredient formulas. Regarding pregnancy and breastfeeding: lobelia is rated likely unsafe and should be avoided in both pregnancy and breastfeeding.

Skullcap and hops lack enough safety data — they are best avoided during pregnancy and breastfeeding. Valerian safety has not been established — it is best avoided in pregnancy and breastfeeding as well.

Talk with your doctor or pharmacist about whether this product is right for you if you are pregnant, breastfeeding, or planning either.

Side effects, ingredient by ingredient Lobelia Skullcap Hops Valerian

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?
  • 4 of the 4 matched ingredients can interact with medications — Lobelia, Hops, Valerian, Skullcap.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: lithium.
  • For scale: 931 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 using this product if you take lithium — lobelia may raise its level. Also check if you take any CNS depressants (sedatives, sleep aids, anxiety drugs, or narcotic painkillers), alprazolam (Xanax), or drink alcohol regularly — skullcap, hops, and valerian can add to drowsiness and cognitive slowing.

If you take drugs broken down through a glucuronidation pathway or certain blood pressure or heart medications, ask before starting as well.

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. Moderate medication interactions have been identified, and safety information is well characterized.

This product may help with sleep, though the evidence is modest and depends partly on its valerian content. It's not for use if you take lithium, sedatives, or certain other medications without checking first.

Lobelia carries real toxicity risk at higher doses. If you're pregnant, breastfeeding, or take any regular medications, talk with your doctor or pharmacist before starting.

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

Assessment coverage: 4 of 5 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Nov 22, 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 N-W, straight from the product label.

Brand Pure Herbs
Net contents 4 Fluid Ounce(s); 120 mL
Market status On market
Date entered into DSLD Nov 22, 2022
DSLD ID 280543
Product type Botanical
Supplement form Liquid
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 N-W by Pure 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 mL
Maximum serving Sizes:
2 mL
Servings per container
60
IngredientAmount% DV
Proprietary Blend1874 mg--
Lobelia Aerial Parts Extract0 NP--
Blue Vervain Aerial Parts Extract0 NP--
Skullcap aerial parts extract0 NP--
Hops flower extract0 NP--
Valerian root extract0 NP--

Other ingredients: None

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.
Suggested/Recommended/Usage/Directions

Directions: For adults, mix 2 mL (abt. 1/2 tsp) of extract in 2 fl. oz (60 mL) water one time daily preferably with a meal.

Shake well before use

Formulation

Beneficial for nervous system support. Helps to promote a feeling of calmness.

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.

Precautions

Warning: Not intended for use by pregnant or nursing women. If you have a medical condition or are taking medication, consult your doctor prior to use.

Discontinue use and consult with your doctor if any adverse reactions occur.

Keep out of reach of children

Brand IP Statement(s)

Pure Herbs, Ltd. Natural Herbal Extracts

FDA Statement of Identity

Dietary Supplement

General Statements

"No expense has been spared to provide the finest nature has to offer."

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

See for yourself

N-W by Pure Herbs label

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

N-W 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 N-W by Pure Herbs

These are the 5 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 mL Dosage formLiquid 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.

Proprietary Blend

1874 mg per serving

Other (inactive) ingredients: None. These complete the product’s ingredient list but are not active constituents.

Interaction report

N-W by Pure Herbs Drug Interactions

Want to check YOUR meds against N-W?

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.

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930Drugs
371 Moderate 559 Minor

Ingredients driving the most interactions

Valerian root extract 902
Hops flower extract 863
Skullcap aerial parts extract 248
Lobelia Aerial Parts Extract 1

Individual Drug Interactions

The ingredients in N-W interact with 930 drugs. Click any drug to see the details.

4 of the 5 ingredients in N-W interact with drugs. Each result below shows which ingredient is responsible. Valerian root extract Hops flower extract Skullcap aerial parts extract Lobelia Aerial Parts Extract

Each ingredient & the kinds of drugs it affects

For each ingredient in N-W 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.

Valerian root extract6 drug types · 902 drugs

Alcohol (Ethanol)

Valerian can have additive sedative effects when used concomitantly with alcohol.
Valerian has sedative effects. Theoretically, valerian might have an additive sedative effect when combined with alcohol. Excessive sedation has been reported in an alcohol-abusing individual who took valerian and Gingko biloba. However, the potential interaction between valerian and alcohol has been disputed in other research. Limited evidence suggests that a combination of valerian 160 mg and lemon balm 80 mg (Euvegal) does not cause further deterioration in reaction ability and reaction rate when taken with alcohol as compared to the effects of alcohol alone.

Likelihood Possible Evidence B
Alprazolam (Xanax)

Valerian can have additive sedative effects when used with alprazolam. Also, valerian in high doses might modestly increase alprazolam levels, though this is not likely to be clinically significant.
Valerian has sedative effects. Theoretically, valerian might cause additive sedation when combined with alprazolam. Also, a small pharmacokinetic study shows that taking valerian extract 1000 mg daily (providing 11 mg valerenic acid) might increase alprazolam levels by about 19%. This might be due to valerian's mild inhibition of cytochrome P450 3A4 (CYP3A4). Despite being statistically significant, this increase is not likely to be clinically significant.

Likelihood Possible Evidence B
Cns Depressants

Valerian can have additive sedative effects when used concomitantly with CNS depressant drugs.
Theoretically, concomitant use of valerian and drugs with sedative and anesthetic properties may cause additive therapeutic and adverse effects.

Likelihood Possible Evidence D
Glucuronidated Drugs

Valerian might weakly inhibit glucuronidation and increase concentrations of drugs metabolized by UGT1A1 and UGT2B7.
In vitro research shows that methanolic valerian extract and valerenic acid might competitively inhibit UDP-glucuronosyltransferase (UGT) 1A1 (UGT1A1) and UGT2B7.

Likelihood Possible Evidence D
Cytochrome P450 2D6 (Cyp2D6) Substrates

Valerian does not seem to have a clinically relevant effect on levels of drugs metabolized by CYP2D6.
Although some in vitro evidence suggests that valerian affects CYP2D6, clinical pharmacokinetic (PK) studies show that valerian is unlikely to affect the CYP2D6 enzyme. In one PK study, taking valerian 1000 mg (providing about 11 mg valerenic acid) nightly for 14 days did not affect the metabolism of dextromethorphan, a CYP2D6 substrate. In another PK study, taking valerian 125 mg three times daily for 28 days did not affect metabolism of debrisoquine, an accepted CYP2D6 probe-substrate.

Likelihood Unlikely Evidence B
Cytochrome P450 3A4 (Cyp3A4) Substrates

Valerian does not seem to have a clinically relevant effect on levels of drugs metabolized by CYP3A4.
Although some in vitro evidence suggests that valerian extract might inhibit or induce CYP3A4, clinical pharmacokinetic (PK) studies show that valerian does not have a clinically significant effect on the CYP3A4 enzyme. In one PK study, taking valerian 125 mg three times daily for 28 days did not affect metabolism of midazolam, an accepted CYP3A4 probe-substrate. In another PK study, taking valerian 1000 mg (providing about 11 mg valerenic acid) nightly for 14 days modestly increases levels of alprazolam, a CYP3A4 substrate, suggesting mild inhibition of CYP3A4. However, this mild inhibition is unlikely to be clinically relevant.

Likelihood Possible Evidence B
Valerian root extract full monograph & interactions

Hops flower extract4 drug types · 863 drugs

Cns Depressants

Theoretically, concomitant use of hops with sedative drugs might cause additive sedation.
Some animal research shows that hops has sedative effects.

Likelihood Possible Evidence D
Estrogens

Theoretically, concomitant use of large amounts of hops might interfere with hormone replacement therapy due to competition for estrogen receptors.
In vitro research suggests that certain hops constituents can competitively bind to estrogen receptors. However, most hops extracts contain very small amounts of these constituents.

Likelihood Possible Evidence D
Cytochrome P450 1A2 (Cyp1A2) Substrates

Hops extract does not seem to affect the metabolism of CYP1A2 substrates.
In vitro research suggests that flavonoid constituents of hops inhibit CYP1A2 enzyme activity. However, a pharmacokinetic study in healthy postmenopausal patients shows that taking a standardized extract of spent hops containing prenylated phenols, as 59.5 mg twice daily for 2 weeks, does not affect levels of caffeine, a CYP1A2 probe substrate.

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

Theoretically, hops extract might alter metabolism of CYP3A4 substrates; however, this effect may not be clinically significant.
Animal research suggests that specific constituents of hops, called lupulones, can induce hepatic CYP3A4 enzyme activity. However, a pharmacokinetic study in healthy postmenopausal patients with normal metabolism shows that taking a standardized extract of spent hops containing prenylated phenols, as 59.5 mg twice daily for 2 weeks, decreases the concentration of alprazolam, a CYP3A4 probe substrate, by 7.6%. This reduction is unlikely to be clinically relevant.

Likelihood Possible Evidence D
Hops flower extract full monograph & interactions

Skullcap aerial parts extract1 drug type · 248 drugs

Cns Depressants

Theoretically, skullcap can have additive effects when used with other CNS depressants.
Animal and clinical research suggests that skullcap can cause sedation and cognitive impairment.

Likelihood Possible Evidence D
Skullcap aerial parts extract full monograph & interactions

Lobelia Aerial Parts Extract1 drug type · 1 drug

Lithium

Lobelia is thought to have diuretic properties. Theoretically, due to these potential diuretic effects, lobelia might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Probable Evidence D
Lobelia Aerial Parts Extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for N-W, from the product label.

Pure Herbs

See all Pure Herbs products
Name
Pure Herbs, Ltd.
City
Sterling Heights
State
MI
Phone Number
(800) 860-4372
Web Address
www.pureherbs.com
Pharmacist Counseling Corner

N-W by Pure Herbs: Common Questions

Does N-W by Pure Herbs interact with any medications?
Yes. Based on its ingredients, N-W has a known interaction with 930 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
N-W contains 5 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 lobelia safe to use?
Lobelia can be toxic, especially at higher doses. Even low doses (as little as 50 mg) can cause nausea, vomiting, diarrhea, and throat irritation. At 600 mg or higher, it can cause serious toxicity with symptoms like sweating, fast heartbeat, tremors, low blood pressure, and even death. Use this product only as directed and talk with your pharmacist about whether it's right for you.
Can I take this while pregnant or breastfeeding?
No. Lobelia is rated likely unsafe for both pregnancy and breastfeeding. Skullcap, hops, and valerian lack enough safety data, so they are best avoided during pregnancy and breastfeeding as well. Talk with your doctor or pharmacist before use if you are pregnant, planning to become pregnant, or breastfeeding.
Will this make me drowsy?
Yes, it's possible. Skullcap, hops, and valerian can all cause drowsiness, cognitive impairment, and mental slowness. Avoid driving or operating machinery until you know how you respond, and don't combine it with alcohol or other sedating drugs without talking to your doctor first.
Does this really help with sleep?
Valerian, one of the ingredients, is rated possibly effective for insomnia based on some trial data. The other ingredients don't have enough evidence to say whether they work for any specific use.
What if I stop taking this after a while?
If you've been taking this long-term, especially the valerian, don't stop suddenly. Abrupt cessation can cause withdrawal symptoms like agitation, insomnia, and anxiety. Taper your dose slowly instead, or ask your pharmacist for guidance.
Can this hurt my liver?
There are rare case reports of liver injury linked to products containing valerian, but they involved multi-ingredient formulas and the connection isn't certain. Still, if you have liver disease or notice yellowing of skin or eyes, dark urine, or unusual fatigue, stop and contact your doctor right away.

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

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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.

N-W label
Go deeper

The Full Monographs Behind N-W’s Ingredients

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

Herb & supplement monograph

Lobelia

Interacts with 1 drug

Lobelia is a traditional herb once used for breathing problems and to help people quit smoking, but reliable evidence supporting these uses is lacking. It can be toxic in higher amounts, cau...

Read the full Lobelia monograph → Herb & supplement monograph

Skullcap

Interacts with 248 drugs

American skullcap is an herb traditionally used to calm anxiety and promote relaxation, but solid human evidence is very limited. It is generally considered relatively safe for short-term us...

Read the full Skullcap monograph → Herb & supplement monograph

Hops

Interacts with 863 drugs

Hops are most often used for sleep and mild anxiety, frequently combined with valerian, but the human evidence is limited and not very strong. They are generally well tolerated when used sho...

Read the full Hops monograph → Herb & supplement monograph

Valerian

Interacts with 902 drugs

Valerian is an herb whose root is widely used as a natural sleep aid and for calming nerves. The evidence is mixed and often weak, so it may help some people sleep but does not work reliably...

Read the full Valerian monograph →
Sources

Sources & How We Checked

N-W'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 61 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.

Lobelia 6 references
  1. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  2. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  3. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  4. McChargue DE, Collins FL Jr, Cohen LM. Effect of non-nicotinic moist snuff replacement and lobeline on withdrawal symptoms during 48-h smokeless tobacco deprivation. Nicotine Tob Res 2002;4:195-200. PubMed
  5. Stead LF, Hughes JR. Lobeline for smoking cessation. Cochrane Database Syst Rev 2000;2:CD000124. PubMed
  6. Plakun, A. L., Ambrus, J., Bross, I., Graham, S., Levin, M. L., and Ross, C. A. Clinical factors in smoking withdrawal: preliminary report. Am J Public Health Nations.Health 1966;56(3):434-441. PubMed

See these in context on the Lobelia monograph →

Skullcap 3 references
  1. Wolfson P, Hoffmann DL. An investigation into the efficacy of Scutellaria lateriflora in healthy volunteers. Altern Ther Health Med 2003;9:74-8.
  2. Awad, R., Arnason, J. T., Trudeau, V., Bergeron, C., Budzinski, J. W., Foster, B. C., and Merali, Z. Phytochemical and biological analysis of skullcap (Scutellaria lateriflora L.): a medicinal plant with anxiolytic properties. Phytomedicine. 2003;10(8):6 PubMed
  3. Brock C, Whitehouse J, Tewfik I, Towell T. American skullcap (Scutellaria lateriflora): a randomised, double-blind placebo-controlled crossover study of its effects on mood in healthy volunteers. Phytother Res 2014;28(5):692-8.

See these in context on the Skullcap monograph →

Hops 15 references
  1. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  2. McGuffin M, Hobbs C, Upton R, Goldberg A, eds. American Herbal Products Association's Botanical Safety Handbook. Boca Raton, FL: CRC Press, LLC 1997.
  3. Zava DT, Dollbaum CM, Blen M. Estrogen and progestin bioactivity of foods, herbs, and spices. Proc Soc Exp Biol Med 1998;217:369-78. PubMed
  4. Milligan SR, Kalita JC, Heyerick A, et al. Identification of a potent phytoestrogen in hops (Humulus lupulus L.) and beer. J Clin Endocrinol Metab 1999;84:2249-52.. PubMed
  5. Milligan SR, Kalita JC, Pocock V, et al. The endocrine activities of 8-prenylnaringenin and related hop (Humulus lupulus L.) flavonoids. J Clin Endocrinol Metab 2000;85:4912-5.. DOI
  6. Henderson MC, Miranda CL, Stevens JF, et al. In vitro inhibition of human P450 enzymes by prenylated flavonoids from hops, Humulus lupulus. Xenobiotica 2000;30:235-51.. PubMed
  7. Mannering, G. J., Shoeman, J. A., and Deloria, L. B. Identification of the antibiotic hops component, colupulone, as an inducer of hepatic cytochrome P-4503A in the mouse. Drug Metab Dispos 1992;20(2):142-147. DOI
  8. Skorska, C., Mackiewicz, B., Gora, A., Golec, M., and Dutkiewicz, J. Health effects of inhalation exposure to organic dust in hops farmers. Ann.Univ Mariae.Curie Sklodowska [Med] 2003;58(1):459-465.
  9. Schiller, H., Forster, A., Vonhoff, C., Hegger, M., Biller, A., and Winterhoff, H. Sedating effects of Humulus lupulus L. extracts. Phytomedicine. 2006;13(8):535-541. PubMed
  10. van Hunsel, F. P. and Kampschoer, P. [Postmenopausal bleeding and dietary supplements: a possible causal relationship with hop- and soy-containing preparations]. Ned.Tijdschr.Geneeskd. 2012;156(41):A5095.
  11. Fenselau, C. and Talalay, P. Is oestrogenic activity present in hops? Food Cosmet.Toxicol. 1973;11(4):597-602. PubMed
  12. Godnic-Cvar, J., Zuskin, E., Mustajbegovic, J., Schachter, E. N., Kanceljak, B., Macan, J., Ilic, Z., and Ebling, Z. Respiratory and immunological findings in brewery workers. Am J Ind Med 1999;35(1):68-75. DOI
  13. Lee KM, Jung JS, Song DK, and et al. Effects of Humulus lupulus extract on the central nervous system in mice. Planta Med 1993;59(Suppl):A691.
  14. Assessment report on Humulus lupulus L., flos. European Medicines Agency, 2014. Available at: https://www.ema.europa.eu/en/documents/herbal-report/final-assessment-report-humulus-lupulus-l-flos_en.pdf. Accessed September 29, 2021.
  15. van Breemen RB, Chen L, Tonsing-Carter A, et al. Pharmacokinetic Interactions of a Hop Dietary Supplement with Drug Metabolism in Perimenopausal and Postmenopausal Women. J Agric Food Chem. 2020;68(18):5212-5220. PubMed

See these in context on the Hops monograph →

Valerian 37 references
  1. Willey LB, Mady SP, Cobaugh DJ, Wax PM. Valerian overdose: a case report. Vet Hum Toxicol 1995;37:364-5.
  2. Kuhlmann J, Berger W, Podzuweit H, Schmidt U. The influence of valerian treatment on "reaction time, alertness and concentration" in volunteers. Pharmacopsychiatry 1999;32:235-41. PubMed
  3. Klepser TB, Klepser ME. Unsafe and potentially safe herbal therapies. Am J Health Syst Pharm 1999;56:125-38. PubMed
  4. Houghton PJ. The scientific basis for the reputed activity of Valerian. J Pharm Pharmacol 1999;51:505-12. PubMed
  5. Garges HP, Varia I, Doraiswamy PM. Cardiac complications and delirium associated with Valerian root withdrawal. [Letter to the Editor]. JAMA 1998;280:1566-7. PubMed
  6. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed
  7. MacGregor FB, Abernethy VE, Dahabra S, et al. Hepatotoxicity of herbal remedies. BMJ 1989;299:1156-7. PubMed
  8. Leathwood PD, Chauffard F. Aqueous extract of valerian reduces latency to fall asleep in man. Planta Med 1985;2:144-8. PubMed
  9. Hadley S, Petry JJ. Valerian. Am Fam Physician 2003;67:1755-8..
  10. Glass JR, Sproule BA, Herrmann N, et al. Acute pharmacological effects of temazepam, diphenhydramine, and valerian in healthy elderly subjects. J Clin Psychopharmacol 2003;23:260-8. PubMed
  11. Lefebvre T, Foster BC, Drouin CE, et al. In vitro activity of commercial valerian root extracts against human cytochrome P450 3A4. J Pharm Pharmaceut Sci 2004;7:265-73.
  12. Yuan CS, Mehendale S, Xiao Y, et al. The gamma-aminobutyric acidergic effects of valerian and valerenic acid on rat brainstem neuronal activity. Anesth Analg 2004;98:353-8. PubMed
  13. Donovan JL, DeVane CL, Chavin KD, et al. Multiple night-time doses of valerian (Valeriana officinalis) had minimal effects on CYP3A4 activity and no effect on CYP2D6 activity in healthy volunteers. Drug Metab Dispos 2004;32:1333-6. PubMed
  14. Gurley BJ, Gardner SF, Hubbard MA, et al. In vivo effects of goldenseal, kava kava, black cohosh, and valerian on human cytochrome P450 1A2, 2D6, 2E1, and 3A4/5 phenotypes. Clin Pharmacol Ther 2005;77:415-26. 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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