Interactions on record — worth a quick check against your medications. Based on 2 of 3 ingredients. Check your meds →
Dietary supplement

Varen Forest Beta-Sitosterol Ingredients & Drug Interactions

by Raw Forest Foods

Varen Forest Beta-Sitosterol label
See full label image
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 Varen Forest Beta-Sitosterol 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

Varen Forest Beta-Sitosterol is a dietary supplement by Raw Forest Foods with 3 active ingredients. Its ingredients are commonly taken for flavoring and culinary use, digestive complaints like bloating and indigestion, boosting absorption of other supplements.Based on those ingredients, 1,085 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Black Pepper Fruit Extract, Stinging Nettle Root 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 Varen Forest Beta-Sitosterol by Raw Forest Foods

Ask about any prescription or over-the-counter medication and we check it for interactions with Varen Forest Beta-Sitosterol by Raw Forest Foods — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
Prefer a human? Send your question to our licensed pharmacists — free, answered by email within 24 hours.

HelloPharmacist Scorecard of Varen Forest Beta-Sitosterol by Raw Forest Foods

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 Jul 11, 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 3 of its 3 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

This product contains 3 active ingredients. Black Pepper Fruit Extract brings piperine, which may enhance how your body absorbs other compounds.

Swedish Flower Pollen Extract and Stinging Nettle Root Extract round out the formula. The capsule itself is made with cellulose, an inert filler.

Does it work?

Insufficient 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
Insufficient

There isn't enough reliable clinical evidence to rate this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Prostate health and urinary function support.
  • We looked for evidence on: Benign prostatic hyperplasia (BPH), Urinary tract infections (UTIs), Urinary symptoms, Lower urinary tract symptoms.
  • The closest evidence on file: Stinging Nettle is rated "Insufficient Reliable Evidence To Rate" for Benign prostatic hyperplasia (BPH) (Natural Medicines).
  • Also on file: Stinging Nettle is rated "Insufficient Reliable Evidence To Rate" for Urinary tract infections (UTIs).

Evidence for what this product actually does is limited. Black pepper has insufficient evidence to rate it for hay fever, asthma, athletic performance, headache, depression, or diarrhea.

Stinging nettle is possibly effective for blood sugar control in diabetes, but the evidence for hay fever, anemia, asthma, prostate health, and gum health is insufficient. We hold no effectiveness data for Swedish Flower Pollen Extract.

The evidence, ingredient by ingredient Black Pepper Stinging Nettle

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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Black pepper is generally well tolerated in food amounts, though concentrated supplements warrant caution — burning aftertaste, indigestion, and reduced taste perception are the most common side effects. Allergic reactions are rare but possible in sensitive people.

Stinging nettle is generally well tolerated for most adults, with constipation or diarrhea being typical. However, stinging nettle is not recommended in pregnancy due to traditional concerns about uterine effects and lack of safety data, and breastfeeding safety is not established — talk with your doctor or pharmacist before use if you're pregnant or nursing.

Side effects, ingredient by ingredient Black Pepper Stinging Nettle

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?
  • 2 of the 2 matched ingredients can interact with medications — Stinging Nettle, Black Pepper.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; lithium.
  • For scale: 1,086 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 before you take this product if you use seizure medications (like phenytoin), blood-pressure drugs (like propranolol), diabetes medications, diuretics, lithium, blood thinners (like warfarin), or antibiotic or HIV drugs. All of these have documented moderate interactions with the black pepper and stinging nettle in this product.

If you're not sure whether your medications are on that list, use the search tool below to verify your exact prescriptions.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with insufficient evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This product is worth a careful medication check before you start. If you take seizure drugs, blood-pressure medications, diabetes pills, diuretics, lithium, or blood thinners, your pharmacist needs to review your list first.

Even if you're on other prescriptions, a quick look at the interaction checker on this page can save you headaches.

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

Assessment coverage: 2 of 3 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Apr 23, 2024.

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 Varen Forest Beta-Sitosterol, straight from the product label.

Brand Raw Forest Foods
Barcode (UPC) 850004627372
Net contents 120 Capsule(s)
Market status On market
Date entered into DSLD Apr 23, 2024
DSLD ID 309831
Product type Botanical
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Seniors/Mature (>50 Years) - Men ONLY, Dairy 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 Varen Forest Beta-Sitosterol by Raw Forest Foods, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
60
UPC/BARCODE
850004627372
IngredientAmount% DV
Black Pepper Fruit Extract10 mg--
Swedish Flower Pollen Extract300 mg--
Stinging Nettle Root Extract400 mg--

Other ingredients: Cellulose

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.
Formula

Our Varen Forest Elevated Beta-Sitosterol Capsules contain clinical grade stinging nettle root extract that has been standardized to contain 45% Beta-Sitosterol, which is then elevated and synergized with Swedish flower pollen extract and fortified with Piperine to maximize absorption.

Stinging nettle root, Swedish flower pollen, & Piperine Pure clinical grade elevated extracts

General Statements

Using hand-selected, premiere ingredients, our products are professionally - and artfully - crafted to meet our discerningly high standards. We invite you to discover the infinite power within.

Discover the infinite power within

Suggested/Recommended/Usage/Directions

Suggested Use: As a dietary supplement, adults take two (2) capsules daily, preferably on an empty stomach. As with all dietary supplements, please consult a qualified healthcare practitioner prior to use.

Precautions

Caution: Do not exceed recommended dose. Do not use if safety seal is damaged or missing.

Pregnant or nursing mothers, children under the age of 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement.

Pregnant or nursing mothers, children under the age of 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement. Keep out of the reach of children.

May contain traces of maltodextrin (used as part of the extraction process).

Storage

Store at room temperature.

Formulation

Vegan

Prostate & pro-androgenic support

No fillers. No drying agents. Never irradiated. This product is GMO free, vegan/vegetarian, and has been manufactured in the USA in an FDA, cGMP certified facility.

This product is GMO free, vegan/vegetarian, and has been manufactured in the USA in an FDA, cGMP certified facility.

Formulated by master herbalists

FDA Statement of Identity

Dietary Supplement

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

Varen Forest Beta-Sitosterol by Raw Forest Foods label

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

Varen Forest Beta-Sitosterol 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 Varen Forest Beta-Sitosterol by Raw Forest Foods

These are the 3 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule 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.

Black Pepper Fruit Extract

Interacts with
1,019 drugs
10 mg per serving Form: Piperine

Black pepper is a common kitchen spice that is generally safe in the amounts used in food. Its extract, piperine, is mostly added to supplements to he...

Black Pepper Fruit Extract monograph & interactions

Swedish Flower Pollen Extract

300 mg per serving

Stinging Nettle Root Extract

Interacts with
164 drugs
400 mg per serving Form: Beta-Sitosterol

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

Stinging Nettle Root Extract monograph & interactions

Other (inactive) ingredients: Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

Varen Forest Beta-Sitosterol by Raw Forest Foods Drug Interactions

Want to check YOUR meds against Varen Forest Beta-Sitosterol?

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
1,085Drugs
1,043 Moderate 42 Minor

Ingredients driving the most interactions

Black Pepper Fruit Extract 1,019
Stinging Nettle Root Extract 164

Individual Drug Interactions

The ingredients in Varen Forest Beta-Sitosterol interact with 1,085 drugs. Click any drug to see the details.

2 of the 3 ingredients in Varen Forest Beta-Sitosterol interact with drugs. Each result below shows which ingredient is responsible. Black Pepper Fruit Extract Stinging Nettle Root Extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Varen Forest Beta-Sitosterol 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.

Black Pepper Fruit Extract17 drug types · 1,019 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, black pepper might increase the risk of bleeding when taken with antiplatelet or anticoagulant drugs.
In vitro research shows that piperine, a constituent of black pepper, seems to inhibit platelet aggregation. This has not been reported in humans.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, black pepper might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research shows that piperine, a constituent of black pepper, can reduce blood glucose levels. Monitor blood glucose levels closely. Dose adjustments might be necessary.

Likelihood Possible Evidence D
Atorvastatin (Lipitor)

Theoretically, black pepper might increase blood levels of atorvastatin.
Animal research shows that taking piperine, a constituent of black pepper, 35 mg/kg can increase the maximum serum concentration of atorvastatin three-fold. This has not been reported in humans.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Theoretically, black pepper might increase the effects and side effects of cyclosporine.
In vitro research shows that piperine, a constituent of black pepper, increases the bioavailability of cyclosporine. This has not been reported in humans.

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

Theoretically, black pepper might increase levels of drugs metabolized by CYP2D6.
In vitro research suggests that some constituents of black pepper inhibit CYP2D6. This has not been reported in humans.

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

Theoretically, black pepper might increase levels of drugs metabolized by CYP3A4.
In vitro research and pharmacokinetic simulation data suggest that piperine, a constituent of black pepper, as well as the pepper fruit seem to inhibit CYP3A4. This has not been reported in humans.

Likelihood Possible Evidence D
Lithium

Theoretically, black pepper might increase blood levels of lithium due to its diuretic effects. The dose of lithium might need to be reduced.
Black pepper is thought to have diuretic properties.

Likelihood Probable Evidence D
Nevirapine (Viramune)

Black pepper might increase blood levels of nevirapine.
Clinical research shows that piperine, a constituent of black pepper, increases the plasma concentration of nevirapine. However, no adverse effects were observed in this study.

Likelihood Probable Evidence D
P-Glycoprotein Substrates

Theoretically, black pepper might increase levels of P-glycoprotein substrates.
In vitro research shows that piperine, a constituent of black pepper, seems to inhibit P-glycoprotein.

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

Theoretically, black pepper might increase the sedative effects of pentobarbital.
Animal research shows that piperine, a constituent of black pepper, increases pentobarbital-induced sleeping time.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

Black pepper might increase blood levels of phenytoin.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption, slow elimination, and increase levels of phenytoin. Taking a single dose of black pepper 1 gram along with phenytoin seems to double the serum concentration of phenytoin. Consuming a soup with black pepper providing piperine 44 mg/200 mL of soup along with phenytoin also seems to increase phenytoin levels when compared with consuming the same soup without black pepper.

Likelihood Possible Evidence B
Propranolol (Inderal)

Black pepper might increase blood levels of propranolol.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of propranolol.

Likelihood Possible Evidence B
Rifampin (Rifadin)

Black pepper might increase blood levels of rifampin.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and serum levels of rifampin.

Likelihood Possible Evidence B
Theophylline

Black pepper might increase blood levels of theophylline.
Clinical research shows that piperine, a constituent of black pepper, seems to increase absorption and slow elimination of theophylline.

Likelihood Possible Evidence D
Amoxicillin (Amoxil, Trimox)

Theoretically, black pepper might increase the effects and side effects of amoxicillin.
Animal research shows that taking piperine, a constituent of black pepper, with amoxicillin increases plasma levels of amoxicillin. This has not been reported in humans.

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

Theoretically, black pepper might increase blood levels of carbamazepine, potentially increasing the effects and side effects of carbamazepine.
One clinical study in patients taking carbamazepine 300 mg or 500 mg twice daily shows that taking a single 20 mg dose of purified piperine, a constituent of black pepper, increases carbamazepine levels. Piperine may increase carbamazepine absorption by increasing blood flow to the GI tract, increasing the surface area of the small intestine, or inhibiting cytochrome P450 3A4 (CYP3A4) in the gut wall. Absorption was significantly increased by 7-10 mcg/mL/hour. The time to eliminate carbamazepine was also increased by 4-8 hours. Although carbamazepine levels were increased, this did not appear to increase side effects. In vitro research also shows that piperine can increase carbamazepine levels by 11% in a time-dependent manner.

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

Theoretically, black pepper might decrease levels and clinical effects of drugs metabolized by CYP1A2.
In vitro research suggests that black pepper induces CYP1A2. This has not been reported in humans.

Likelihood Possible Evidence D
Black Pepper Fruit Extract full monograph & interactions

Stinging Nettle Root 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 Root Extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Varen Forest Beta-Sitosterol, from the product label.

Raw Forest Foods

See all Raw Forest Foods products
Name
RAW Forest Foods LLC
Street Address
11 Elmwood Ave, Suite 102
City
Burlington
State
VT
ZipCode
05402
Phone Number
(802) 349-1347
Web Address
Rawforestfoods.com
Pharmacist Counseling Corner

Varen Forest Beta-Sitosterol by Raw Forest Foods: Common Questions

Does Varen Forest Beta-Sitosterol by Raw Forest Foods interact with any medications?
Yes. Based on its ingredients, Varen Forest Beta-Sitosterol has a known interaction with 1,085 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Varen Forest Beta-Sitosterol contains 3 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 black pepper safe to take as a supplement?
Black pepper is safe in food amounts, but concentrated supplements should be used cautiously and ideally under medical advice. The main side effects are a burning aftertaste, indigestion, and reduced taste perception. Allergic reactions are rare but can happen in sensitive people.
Can I take this if I'm pregnant or breastfeeding?
Stinging nettle is not recommended in pregnancy because of traditional concerns about effects on the uterus, and safety during breastfeeding has not been established. Talk with your doctor or pharmacist before using this product if you're pregnant, planning to become pregnant, or nursing.
What is stinging nettle supposed to do?
Stinging nettle is possibly effective for helping manage blood sugar in diabetes. Evidence for hay fever, anemia, asthma, prostate health, and gum health is insufficient to rate it.
Does black pepper in this product really change how my medications work?
Yes — the piperine in black pepper can increase blood levels of several drugs by changing how your body absorbs and eliminates them. This matters most for seizure medications, blood-pressure drugs, and some antibiotics. Your pharmacist can tell you if your specific medications are affected.
What are the most common side effects?
Black pepper may cause a burning aftertaste, indigestion, or reduced taste perception. Stinging nettle may cause constipation or diarrhea. These are generally mild, but stop and talk with your pharmacist if they're bothersome or don't go away.

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

Not sure if Varen Forest Beta-Sitosterol is safe with your meds?

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Ask a pharmacist

Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

Varen Forest Beta-Sitosterol label
Go deeper

The Full Monographs Behind Varen Forest Beta-Sitosterol’s Ingredients

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

Herb & supplement monograph

Black Pepper

Interacts with 1,019 drugs

Black pepper is a common kitchen spice that is generally safe in the amounts used in food. Its extract, piperine, is mostly added to supplements to help the body absorb other ingredients (li...

Read the full Black Pepper monograph → 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 →
Sources

Sources & How We Checked

Varen Forest Beta-Sitosterol'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 52 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.

Black Pepper 29 references
  1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  3. Bano G, Amla V, Raina RK, et al. The effect of piperine on pharmacokinetics of phenytoin in healthy volunteers. Planta Med 1987;53:568-9. PubMed
  4. Bano G, et al. Effect of piperine on bioavailability and pharmacokinetics of propranolol and theophylline in healthy volunteers. Eur J Clin Pharmacol 1991;41;615-7. PubMed
  5. Cohle SD, Trestrail JD III, Graham MA, et al. Fatal pepper aspiration. Am J Dis Child 1988;142:633-6. PubMed
  6. Bhardwaj RK, Glaeser H, Becquemont L, et al. Piperine, a major constituent of black pepper, inhibits human P-glycoprotein and CYP3A4. J Pharmacol Exp Ther 2002;302:645-50. PubMed
  7. Velpandian T, Jasuja R, Bhardwaj RK, et al. Piperine in food: interference in the pharmacokinetics of phenytoin. Eur J Drug Metab Pharmacokinet 2001;26:241-7. PubMed
  8. Pattanaik S, Hota D, Prabhakar S, et al. Pharmacokinetic interaction of a single dose of piperine with steady-state carbamazepine in epilepsy patients. Phytother Res 2009;23:1281-6.
  9. Munakata, M., Kobayashi, K., Niisato-Nezu, J., Tanaka, S., Kakisaka, Y., Ebihara, T., Ebihara, S., Haginoya, K., Tsuchiya, S., and Onuma, A. Olfactory stimulation using black pepper oil facilitates oral feeding in pediatric patients receiving long-term en
  10. Myers, B. M., Smith, J. L., and Graham, D. Y. Effect of red pepper and black pepper on the stomach. Am J Gastroenterol 1987;82(3):211-214.
  11. Raghavendra, R. H. and Naidu, K. A. Spice active principles as the inhibitors of human platelet aggregation and thromboxane biosynthesis. Prostaglandins Leukot.Essent.Fatty Acids 2009;81(1):73-78. PubMed
  12. Subehan, Usia, T., Kadota, S., and Tezuka, Y. Mechanism-based inhibition of human liver microsomal cytochrome P450 2D6 (CYP2D6) by alkamides of Piper nigrum. Planta Med 2006;72(6):527-532.
  13. Kasibhatta, R. and Naidu, M. U. Influence of piperine on the pharmacokinetics of nevirapine under fasting conditions: a randomised, crossover, placebo-controlled study. Drugs R.D. 2007;8(6):383-391. PubMed
  14. Usia, T., Iwata, H., Hiratsuka, A., Watabe, T., Kadota, S., and Tezuka, Y. CYP3A4 and CYP2D6 inhibitory activities of Indonesian medicinal plants. Phytomedicine. 2006;13(1-2):67-73. PubMed
  15. Mujumdar, A. M., Dhuley, J. N., Deshmukh, V. K., Raman, P. H., Thorat, S. L., and Naik, S. R. Effect of piperine on pentobarbitone induced hypnosis in rats. Indian J Exp.Biol. 1990;28(5):486-487.
  16. Panda, S. and Kar, A. Piperine lowers the serum concentrations of thyroid hormones, glucose and hepatic 5'D activity in adult male mice. Horm.Metab Res. 2003;35(9):523-526. PubMed
  17. Lawless, H. and Stevens, D. A. Effects of oral chemical irritation on taste. Physiol Behav. 1984;32(6):995-998. PubMed
  18. Hiwale, A. R., Dhuley, J. N., and Naik, S. R. Effect of co-administration of piperine on pharmacokinetics of beta-lactam antibiotics in rats. Indian J Exp.Biol. 2002;40(3):277-281.
  19. Han, Y., Chin Tan, T. M., and Lim, L. Y. In vitro and in vivo evaluation of the effects of piperine on P-gp function and expression. Toxicol.Appl.Pharmacol. 8-1-2008;230(3):283-289. PubMed
  20. Sharma, P., Varma, M. V., Chawla, H. P., and Panchagnula, R. In situ and in vivo efficacy of peroral absorption enhancers in rats and correlation to in vitro mechanistic studies. Farmaco 2005;60(11-12):874-883. PubMed
  21. Aher, S., Biradar, S., Gopu, C. L., and Paradkar, A. Novel pepper extract for enhanced P-glycoprotein inhibition. J Pharm.Pharmacol. 2009;61(9):1179-1186. PubMed
  22. Zutshi, R. K., Singh, R., Zutshi, U., Johri, R. K., and Atal, C. K. Influence of piperine on rifampicin blood levels in patients of pulmonary tuberculosis. J Assoc.Physicians India 1985;33(3):223-224.
  23. Marotta, R. B. and Floch, M. H. Diet and nutrition in ulcer disease. Med Clin North Am 1991;75(4):967-979. PubMed
  24. Subehan, Usia, T., Iwata, H., Kadota, S., and Tezuka, Y. Mechanism-based inhibition of CYP3A4 and CYP2D6 by Indonesian medicinal plants. J Ethnopharmacol. 5-24-2006;105(3):449-455. PubMed
  25. Gimenez L, Zacharisen M. Severe pepper allergy in a young child. WMJ. 2011 Jun;110(3):138-9.
  26. Ren T, Yang M, Xiao M, Zhu J, Xie W, Zuo Z. Time-dependent inhibition of carbamazepine metabolism by piperine in anti-epileptic treatment. Life Sci. 2019;218:314-323. PubMed
  27. Thomas AB, Choudhary DC, Raje A, Nagrik SS. Pharmacokinetics and pharmacodynamic herb-drug interaction of piperine with atorvastatin in rats. J Chromatogr Sci 2021;59(4):371-80. PubMed
  28. Haron MH, Dale O, Martin K, et al. Evaluation of the Herb-Drug Interaction Potential of Commonly Used Botanicals on the US Market with Regard to PXR- and AhR-Mediated Influences on CYP3A4 and CYP1A2. J Diet Suppl 2022. PubMed
  29. Lin F, Hu Y, Zhang Y, Zhao L, Zhong D, Liu J. Predicting Food-Drug Interactions between Piperine and CYP3A4 Substrate Drugs Using PBPK Modeling. Int J Mol Sci 2024;25(20):10955. PubMed

See these in context on the Black Pepper monograph →

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.
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See these in context on the Stinging Nettle monograph →

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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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