Interactions on record — worth a quick check against your medications. Check your meds →
Dietary supplement

TestoQuench For Men Ingredients & Drug Interactions

by Douglas Laboratories

Capsule Category: Botanical With Nutrients
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

TestoQuench For Men is a dietary supplement by Douglas Laboratories with 6 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, 1,188 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are BioPerine, Magnolia officinalis bark extract, Holy Basil. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of TestoQuench For Men by Douglas Laboratories

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

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 1 of its 6 active ingredients.
  • “TestoQuench for Men” is listed as a grouped ingredient — the label gives one combined amount (2,880 mg) without saying how much of each component you get.

TestoQuench For Men contains six active ingredients. BioPerine (black pepper extract) is included for absorption enhancement.

Saw palmetto berry extract, stinging nettle leaf extract, and pygeum africanum bark extract are herbal ingredients traditionally used for men's urinary and prostate health. Magnolia officinalis bark extract and holy basil round out the formula.

The capsules also contain inactive ingredients — hydroxypropyl methylcellulose, silica, and hydroxypropyl cellulose — which are fillers and binders.

Does it work?

Strong 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
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Prostate health and urinary function in men.
  • We looked for evidence on: Benign prostatic hyperplasia (BPH), Non-neurogenic lower urinary tract symptoms (LUTS), Chronic prostatitis and chronic pelvic pain syndrome (CP/CPPS), Prostatitis, Prostate comfort, Male urinary health.
  • The strongest evidence on file: Pygeum is rated "Likely Effective" for Benign prostatic hyperplasia (BPH) (Natural Medicines).
  • Also on file: Saw Palmetto is rated "Possibly Ineffective" for Benign prostatic hyperplasia (BPH).
  • Also on file: Stinging Nettle is rated "Insufficient Reliable Evidence To Rate" for Benign prostatic hyperplasia (BPH).

The evidence for this product's ingredients is limited. Pygeum is likely effective for benign prostatic hyperplasia (BPH), and saw palmetto is possibly effective for a specific prostate procedure (transurethral resection of the prostate, or TURP), though it's rated possibly ineffective for BPH itself.

Stinging nettle is possibly effective for diabetes. Magnolia shows possible effectiveness for gingivitis.

For most other uses — including athletic performance, anxiety, headache, asthma, and respiratory infections — the evidence we hold is insufficient to rate these ingredients. Holy basil's effectiveness for diabetes and other conditions listed is not established in our data.

The evidence, ingredient by ingredient Black Pepper Saw Palmetto Stinging Nettle Magnolia Pygeum Holy Basil

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.

BioPerine (black pepper) is generally well tolerated in food amounts, though concentrated supplements should be used cautiously. The most common side effects are burning aftertaste, indigestion, and reduced taste perception; allergic reactions are rare.

Saw palmetto is generally well tolerated but can cause abdominal pain, constipation, diarrhea, dizziness, fatigue, headache, nausea, and changes in libido. Stinging nettle may cause constipation or diarrhea.

Magnolia and holy basil are generally well tolerated short-term; holy basil may cause loose stools and nausea. Pygeum is associated with nausea and abdominal pain in some studies, though rates were similar to placebo.

Pregnancy and breastfeeding safety data are not on file for most of these ingredients.

Side effects, ingredient by ingredient Black Pepper Saw Palmetto Stinging Nettle Magnolia Pygeum Holy Basil

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?
  • 5 of the 6 matched ingredients can interact with medications — Magnolia, Stinging Nettle, Black Pepper, Saw Palmetto, Holy Basil.
  • 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: 1,189 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking this product, double-check if you use blood thinners or antiplatelet drugs (like warfarin, aspirin, or clopidogrel) — saw palmetto, magnolia, and holy basil may all increase bleeding risk. Check diabetes medications, since stinging nettle and holy basil may lower blood sugar further.

If you take propranolol (Inderal), phenytoin (Dilantin), or theophylline, the black pepper in this product can raise their blood levels. Also verify use if you're on birth control pills, estrogen, lithium, diuretics, cyclosporine, nevirapine, rifampin, or atorvastatin — all have documented interactions with ingredients here.

Check your own medication Run your meds through the checker above

The bottom line

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

This product is aimed at men concerned with prostate and urinary health, and pygeum has solid evidence for BPH. However, several ingredients interact with common medications — especially blood thinners, diabetes drugs, and seizure or heart medications — so check your prescriptions before you start.

Talk to your pharmacist or doctor if you take any regular medications, use birth control pills, or have bleeding concerns.

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

Assessment coverage: 6 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Aug 23, 2020.

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 TestoQuench For Men, straight from the product label.

Brand Douglas Laboratories
Barcode (UPC) 310539978238
Net contents 120 Vegetarian Capsule(s)
Market status On market
Date entered into DSLD Aug 23, 2020
DSLD ID 232865
Product type Botanical With Nutrients
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult Male (18-50 Years), 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 TestoQuench For Men by Douglas Laboratories, 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 Vegetarian Capsule(s)
Maximum serving Sizes:
4 Vegetarian Capsule(s)
Servings per container
30
UPC/BARCODE
310539978238
IngredientAmount% DV
BioPerine20 mg, 10 mg--
Saw Palmetto berry extract0 NP, 0 NP--
Stinging Nettle leaf extract0 NP, 0 NP--
Magnolia officinalis bark extract0 NP, 0 NP--
TestoQuench for Men2880 mg, 1440 mg--
Pygeum africanum bark extract0 NP, 0 NP--
Holy Basil0 NP, 0 NP--

Other ingredients: Hydroxypropyl Methylcellulose, Silica, Hydroxypropyl 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.
Suggested/Recommended/Usage/Directions

Suggested Usage: As a dietary supplement, adults take 2-4 capusles daily or as directed by your health professional.

Precautions

Warning: Not to be taken by pregnant or lactating women. If you have any health condition or are taking any medication, consult your health professional before use.

Keep out of the reach of children.

Use only if safety seal is intact.

Brand IP Statement(s)

BioPerine is a registered trademark of Sabinsa Corporation.

Storage

Store in a cool, dry place.

Formulation

Gluten-free, Non-GMO

Hormone specific formulation

FDA Disclaimer Statement

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

General Statements

Contents may not fill package in order to accommodate required labeling. Please rely on stated quantity. Scan to learn about our manufacturing excellence

Servings per container 60 30

FDA Statement of Identity

Dietary Supplement

Formula

Support for prostate health and testosterone balance in men

See for yourself

TestoQuench For Men by Douglas Laboratories label

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

What’s inside

The Ingredients in TestoQuench For Men by Douglas Laboratories

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Vegetarian 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.

BioPerine

Interacts with
1,019 drugs
20 mg per serving

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...

BioPerine monograph & interactions

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

Interaction report

TestoQuench For Men by Douglas Laboratories Drug Interactions

Want to check YOUR meds against TestoQuench For Men?

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
1,188Drugs
1,157 Moderate 31 Minor

Each ingredient & the kinds of drugs it affects

For each ingredient in TestoQuench For Men 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.

BioPerine17 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

Magnolia officinalis bark extract2 drug types · 351 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, magnolia might have additive effects and increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
In vitro research shows that the chemicals magnolol and honokiol, isolated from magnolia bark, inhibit platelet aggregation that is experimentally induced by collagen and arachidonic acid. However, they do not inhibit platelet aggregation that is induced by adenosine diphosphate, platelet-activating factor, or thrombin. This interaction has not been reported in humans.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, concomitant use of large doses of magnolia bark and CNS depressants might have additive effects.
In vitro and animal research shows that constituents extracted from magnolia bark, especially honokiol and magnolol, have sedative effects. These effects may be due to the inhibition of catecholamine release and modulation of gamma-aminobutyric acid-A (GABA-A) receptors.

Likelihood Possible Evidence D

Holy Basil3 drug types · 212 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, holy basil seed oil might increase the risk of bleeding when used with anticoagulant or antiplatelet drugs.
Animal research shows that holy basil seed oil can prolong bleeding time, possibly due to inhibition of platelet aggregation. However, it is not known if this occurs in humans.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, holy basil might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Small clinical studies show that taking holy basil can decrease fasting blood glucose and other measures of glycemic control in patients with type 2 diabetes.

Likelihood Possible Evidence B
Pentobarbital (Nembutal)

Theoretically, holy basil seed oil might increase the sedative effects of pentobarbital.
Animal research shows that holy basil seed oil increases pentobarbitone-induced sleeping time. However, it is not known if this occurs in humans or if this applies to other barbiturates or sedatives.

Likelihood Possible Evidence D

Saw Palmetto berry extract3 drug types · 174 drugs

Anticoagulant/Antiplatelet Drugs

Saw palmetto might increase the risk of bleeding with anticoagulant or antiplatelet drugs.
Saw palmetto is reported to prolong bleeding time. Theoretically, it might increase the risk of bleeding when used concomitantly with anticoagulant or antiplatelet drugs.

Likelihood Possible Evidence D
Contraceptive Drugs

Saw palmetto might reduce the effectiveness of contraceptive drugs.
Saw palmetto might have antiestrogenic effects. Theoretically, it might interfere with contraceptive drugs taken concomitantly.

Likelihood Possible Evidence B
Estrogens

Saw palmetto might reduce the effectiveness of estrogens.
Saw palmetto might have antiestrogenic effects. Theoretically, it might interfere with estrogens taken concomitantly.

Likelihood Possible Evidence B

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
The maker

Brand information

Manufacturer and brand details for TestoQuench For Men, from the product label.

Douglas Laboratories

See all Douglas Laboratories products
Name
Douglas Laboratories
Street Address
600 Boyce Road
City
Pittsburgh
State
PA
ZipCode
15205
Phone Number
1.800.245.4440
Web Address
www.douglaslabs.com
Pharmacist Counseling Corner

TestoQuench For Men by Douglas Laboratories: Common Questions

Does TestoQuench For Men by Douglas Laboratories interact with any medications?
Yes. Based on its ingredients, TestoQuench For Men has a known interaction with 1,188 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
TestoQuench For Men contains 6 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.
Can I take this if I'm on a blood thinner?
No — not without talking to your pharmacist or doctor first. Saw palmetto, magnolia, and holy basil all carry a Moderate interaction with blood thinners and antiplatelet drugs like warfarin or aspirin, and they may increase your bleeding risk. You need personalized advice on whether this product is right for you.
Will this affect my birth control?
Possibly. Saw palmetto may reduce how well estrogen-containing birth control pills work, which could affect their effectiveness. Talk with your doctor or pharmacist before adding this product.
Can I take this if I have diabetes and use medication?
Check with your pharmacist first. Stinging nettle and holy basil both lower blood sugar, so taking them with diabetes medications could drop your glucose too low. Your doctor may need to adjust your dose.
Does pygeum work for prostate problems?
Pygeum is likely effective for benign prostatic hyperplasia (BPH). However, saw palmetto — another ingredient in this product for prostate health — is rated possibly ineffective for BPH itself, so the overall benefit of the blend isn't clear.
What are the most common side effects?
Black pepper may cause a burning aftertaste or indigestion. Saw palmetto can trigger abdominal pain, diarrhea, or headache. Holy basil and stinging nettle may cause loose stools. Most effects are mild and reversible.
Is it safe to take while pregnant or breastfeeding?
Saw palmetto is rated likely unsafe in pregnancy and should be avoided while breastfeeding. Safety data for stinging nettle, magnolia, holy basil, and pygeum in pregnancy or lactation is not on file or advises against use. Talk with your doctor or pharmacist before using this product if you're pregnant or nursing.

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

Not sure if TestoQuench For Men 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.

TestoQuench For Men label
Go deeper

The Full Monographs Behind TestoQuench For Men’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

Saw Palmetto

Interacts with 174 drugs

Saw palmetto is a plant extract most often used for urinary symptoms linked to an enlarged prostate (BPH). The best research suggests it works no better than a placebo for most men, though i...

Read the full Saw Palmetto 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 →
Herb & supplement monograph

Magnolia

Interacts with 351 drugs

Magnolia bark and flower buds have a long history in traditional Chinese and Japanese medicine, often for stress, sleep, and digestion. Modern human research is still limited, so we can't be...

Read the full Magnolia monograph →
Herb & supplement monograph

Pygeum

Pygeum is an extract from the bark of the African cherry tree that is most often used to ease urinary symptoms linked to an enlarged prostate. Some studies suggest modest benefit for these s...

Read the full Pygeum monograph →
Herb & supplement monograph

Holy Basil

Interacts with 212 drugs

Holy basil (tulsi) is a traditional Ayurvedic herb most often used today for stress and general wellness, but the human evidence is mostly small and preliminary. It is generally well tolerat...

Read the full Holy Basil monograph →
Sources

Sources & How We Checked

TestoQuench For Men'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 94 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.
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Saw Palmetto 22 references
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Stinging Nettle 23 references
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Magnolia 9 references
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Pygeum 3 references
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Holy Basil 8 references
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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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