Interactions on record — worth a quick check against your medications. Based on 14 of 15 ingredients. Check your meds →
Dietary supplement

Testosterone Power Ingredients & Drug Interactions

by Nature's Truth

Testosterone Power label
See full label image
Softgel Capsule Category: Other Combinations
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 Testosterone Power 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

Testosterone Power is a dietary supplement by Nature's Truth with 15 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, 1,518 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Ashwagandha Root Extract , Bioperine Black Pepper Fruit Extract, L-Arginine Hydrochloride. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Testosterone Power by Nature's Truth

Ask about any prescription or over-the-counter medication and we check it for interactions with Testosterone Power by Nature's Truth — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Testosterone Power by Nature's Truth

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

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 2 of its 15 active ingredients.
  • “Herbal Testosterone Max Blend” is a proprietary blend — the label gives one combined amount (1,000 mg) without saying how much of each component you get.
  • “Ultra Vitality Blend” is a proprietary blend — the label gives one combined amount (200 mg) without saying how much of each component you get.
  • “Bioactive Phytosterol Complex” is a proprietary blend — the label doesn't break down how much of each component you get.

Testosterone Power contains 15 active ingredients aimed at supporting male vitality and sexual function. The main amino acids are L-Citrulline and L-Arginine Hydrochloride, which work by increasing nitric oxide to improve blood flow.

Herbal extracts include Saw Palmetto Berry for prostate support, Tribulus Fruit and Tongkat Ali Root for sexual function and athletic performance, Ashwagandha Root for stress and sleep, Stinging Nettle Leaf for urinary and metabolic health, and Fenugreek Seed for sexual arousal and blood sugar. Supporting ingredients are Diindolylmethane, Indole-3-Carbinol, and Chrysin—plant compounds with antioxidant roles—plus Bioperine Black Pepper Fruit Extract for absorption, Pumpkin Seed Oil, and Cissus Leaf Extract.

The product also contains inactive ingredients like gelatin capsule, glycerin, beeswax, lecithin, and colorants.

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: Male performance and vitality support.
  • We looked for evidence on: Age-related testosterone deficiency, Athletic performance, Benign prostatic hyperplasia (BPH), Erectile dysfunction (ED), Fatigue, Sexual function — and 2 related terms.
  • The strongest evidence on file: Pumpkin is rated "Possibly Effective" for Benign prostatic hyperplasia (BPH) (Natural Medicines).
  • Also on file: L-citrulline is rated "Possibly Effective" for Athletic performance.
  • Also on file: Tribulus is rated "Possibly Ineffective" for Athletic performance.

Evidence for this product's ingredients is mixed. Tribulus Fruit Extract is possibly effective for sexual dysfunction, and Fenugreek Seed is possibly effective for sexual dysfunction and arousal as well as diabetes support.

L-Citrulline is possibly effective for athletic performance. Pumpkin Seed Oil is possibly effective for benign prostatic hyperplasia.

Cissus Leaf Extract is possibly effective for weight management. Ashwagandha Root is possibly effective for insomnia, anxiety, and stress.

However, many ingredients have insufficient evidence or show no clear benefit—Saw Palmetto for benign prostatic hyperplasia is rated possibly ineffective, Tribulus for athletic performance is possibly ineffective, and Tongkat Ali for athletic performance is possibly ineffective. For most of the conditions the blend might target, the data is either limited or absent in our records.

The evidence, ingredient by ingredient Black Pepper Pumpkin Saw Palmetto Ashwagandha Stinging Nettle Tribulus Eurycoma Longifolia Cissus Quadrangularis

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 13 of the 14 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 14 of 14.
  • General safety write-ups exist for 14 of 14.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most ingredients are generally well tolerated in short-term use, but long-term safety data are limited for many of them. Common side effects are mild—gastrointestinal upset, headache, nausea, and diarrhea appear across several ingredients.

More serious but rare effects have been reported: ashwagandha has been linked to liver problems and cases of bleeding in the brain; saw palmetto to heart rhythm abnormalities; stinging nettle to drug-induced liver injury; and tribulus to kidney and liver damage in very high doses. For pregnancy, L-Citrulline, Saw Palmetto, Ashwagandha, Stinging Nettle, Tribulus, and Fenugreek should be avoided—the safety data advise against them or they lack enough data to be safe.

For breastfeeding, safety is not established for most ingredients; talk with your doctor or pharmacist before use. Pregnancy and lactation data are not on file for L-Arginine Hydrochloride, Diindolylmethane, Indole-3-Carbinol, Chrysin, Black Pepper, Tongkat Ali, Pumpkin Seed Oil, and Cissus Leaf Extract—discuss with your provider if you're pregnant or nursing.

Side effects, ingredient by ingredient Black Pepper Pumpkin Saw Palmetto Ashwagandha Stinging Nettle Tribulus Eurycoma Longifolia Cissus Quadrangularis

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?
  • 14 of the 14 matched ingredients can interact with medications — Tribulus, Stinging Nettle, Fenugreek, Black Pepper, Pumpkin, among others.
  • 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: 1,519 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 pharmacist before using this product if you take any of the following: ACE inhibitors or other blood pressure drugs (risk of very low blood pressure or high potassium); blood thinners like warfarin, clopidogrel, or aspirin; diabetes medications; thyroid hormones; benzodiazepines or other sedatives; lithium; birth control pills or estrogen therapy; beta-blockers like propranolol or metoprolol; theophylline; phenytoin; or sildenafil. The medication count reflects all individual drugs across all ingredients—use the search tool on this page to verify your specific medications.

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.

Testosterone Power may appeal to men seeking support for sexual function, athletic performance, or prostate health, since several ingredients have some evidence for these uses. However, if you take blood pressure medications, diabetes drugs, blood thinners, heart medications, or psychiatric drugs, you'll need to check your exact prescriptions with a pharmacist before starting—the interactions are real and potentially serious.

Long-term safety data are thin for most of these herbal blends, and if you're pregnant or breastfeeding, several ingredients should be avoided entirely.

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

Assessment coverage: 14 of 15 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Mar 22, 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 Testosterone Power, straight from the product label.

Brand Nature's Truth
Barcode (UPC) 840093115461
Net contents 60 Liquid Max Softgel(s)
Market status On market
Date entered into DSLD Mar 22, 2024
DSLD ID 306831
Product type Other Combinations
Supplement form Softgel Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult Male (18-50 Years), Gluten Free, 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 Testosterone Power by Nature's Truth, 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:
4 Liquid Max Softgel(s)
Maximum serving Sizes:
4 Liquid Max Softgel(s)
Servings per container
15
UPC/BARCODE
840093115461
IngredientAmount% DV
L-Citrulline0 NP--
Saw Palmetto Berry Extract0 NP--
L-Arginine Hydrochloride0 NP--
Diindolylmethane0 NP--
Ashwagandha Root Extract 0 NP--
Stinging Nettle Leaf Extract0 NP--
Indole-3-Carbinol0 NP--
Chrysin0 NP--
Bioperine Black Pepper Fruit Extract10 mg--
Sterol Esters0 NP--
Tribulus Fruit Extract0 NP--
Tongkat Ali Root Extract0 NP--
Pumpkin Seed Oil, Extra Virgin2400 mg--
Herbal Testosterone Max Blend1000 mg--
Cissus Leaf Extract0 NP--
TestoPlus Fenugreek Seed Extract0 NP--
Ultra Vitality Blend200 mg--
Bioactive Phytosterol Complex0 NP--
Amino Flow Complex100 mg--

Other ingredients: Gelatin, Glycerin, Yellow Beeswax, Sunflower Lecithin, Carmine, Turmeric Oleoresin, Titanium Dioxide

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.
Seals/Symbols

100% Quality Satisfaction Guarantee

Our Non-GMO Pledge Visit our website

Formulation

Therapeutic grade

2 in-1 formula for men Rapid flow Vitality and performance formula

Gluten free Non GMO

No gluten, wheat, yeast, milk, lactose, artificial flavor, artificial sweetener, preservatives. Non-GMO

General Statements

Vitamins Gold series

Formula

Male performance

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Directions: For adults, take four (4) liquid max softgels per day in divided doses, preferably with meals. For more immediate results, take four (4) liquid max softgels one hour before activity.

Precautions

Warning: This product is intended for use by men and is not intended for use by women.

If you are taking any medications, including blood pressure or vasodilating medications, or have any medical condition, consult your doctor before use.

If any adverse reactions occur, immediately stop using this product and consult your doctor.

Not intended for use by persons under the age of 18. Keep out of reach of children.

If seal under cap is damaged or missing, do not use.

Warning: Consuming this product can expose you to chemicals including lead, which is known to the state of California to cause birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov/food.

Storage

Store in a cool, dry place.

Brand IP Statement(s)

BioPerine is a registered trademark of Sabinsa Corporation.

Copyright 2021 Nature's Truth LLC

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

Testosterone Power by Nature's Truth label

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

Testosterone Power 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 Testosterone Power by Nature's Truth

These are the 15 active ingredients this product is made of. Select any to open its full monograph.

Serving size4 Liquid Max Softgel(s) Dosage formSoftgel Capsule Servings per container15 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 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...

Bioperine Black Pepper Fruit Extract monograph & interactions

Pumpkin Seed Oil, Extra Virgin

Interacts with
1 drug
2400 mg per serving

Pumpkin is a nutritious squash, and its seeds and seed oil are the parts most often used as supplements, mainly for urinary and prostate symptoms. The...

Pumpkin Seed Oil, Extra Virgin monograph & interactions

Ultra Vitality Blend

200 mg per serving

Amino Flow Complex

100 mg per serving

Other (inactive) ingredients: Gelatin, Glycerin, Yellow Beeswax, Sunflower Lecithin, Carmine, Turmeric Oleoresin, Titanium Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Testosterone Power by Nature's Truth Drug Interactions

Want to check YOUR meds against Testosterone Power?

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
1,518Drugs
1,460 Moderate 58 Minor

Ingredients driving the most interactions

Ashwagandha Root Extract 1,372
Bioperine Black Pepper Fruit Extract 1,019
L-Arginine Hydrochloride 403
TestoPlus Fenugreek Seed Extract 389
Chrysin 358

Individual Drug Interactions

The ingredients in Testosterone Power interact with 1,518 drugs. Click any drug to see the details.

14 of the 15 ingredients in Testosterone Power interact with drugs. Each result below shows which ingredient is responsible. Ashwagandha Root Extract Bioperine Black Pepper Fruit Extract L-Arginine Hydrochloride TestoPlus Fenugreek Seed Extract Chrysin Indole-3-Carbinol Diindolylmethane Tribulus Fruit Extract Tongkat Ali Root Extract L-Citrulline Saw Palmetto Berry Extract Stinging Nettle Leaf Extract Cissus Leaf Extract Pumpkin Seed Oil, Extra Virgin

Each ingredient & the kinds of drugs it affects

For each ingredient in Testosterone Power 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.

Ashwagandha Root Extract 10 drug types · 1,372 drugs

Antidiabetes Drugs

Theoretically, taking ashwagandha with antidiabetes drugs might increase the risk of hypoglycemia.
There is preliminary clinical evidence suggesting that ashwagandha might lower blood glucose levels. Theoretically, ashwagandha might have additive effects when used with antidiabetes drugs and increase the risk of hypoglycemia.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, taking ashwagandha with antihypertensive drugs might increase the risk of hypotension.
Animal research suggests that ashwagandha might lower systolic and diastolic blood pressure. Theoretically, ashwagandha might have additive effects when used with antihypertensive drugs and increase the risk of hypotension.

Likelihood Possible Evidence D
Benzodiazepines

Theoretically, taking ashwagandha might increase the sedative effects of benzodiazepines.
There is preliminary evidence that ashwagandha might have an additive effect with diazepam (Valium) and clonazepam (Klonopin). This may also occur with other benzodiazepines.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, taking ashwagandha might increase the sedative effects of CNS depressants.
Ashwagandha seems to have sedative effects. Theoretically, this may potentiate the effects of barbiturates, other sedatives, and anxiolytics.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, taking ashwagandha with hepatotoxic drugs might increase the risk of liver damage.
Ashwagandha has been linked to cases of acute hepatitis, liver failure, hepatic encephalopathy, autoimmune hepatitis, the need for liver transplantation, and death due to liver failure.

Likelihood Possible Evidence D
Immunosuppressants

Theoretically, taking ashwagandha might decrease the effects of immunosuppressants.
Ashwagandha has demonstrated immunostimulant effects in humans. Animal research has shown that ashwagandha can attenuate the immunosuppression caused by cyclophosphamide.

Likelihood Possible Evidence D
Thyroid Hormone

Ashwagandha might increase the effects and adverse effects of thyroid hormone.
Concomitant use of ashwagandha with thyroid hormones may cause additive therapeutic and adverse effects. Preliminary clinical research and animal studies suggest that ashwagandha boosts thyroid hormone synthesis and secretion. In one clinical study, ashwagandha increased triiodothyronine (T3) and thyroxine (T4) levels by 41.5% and 19.6%, respectively, and reduced serum TSH levels by 17.4% from baseline in adults with subclinical hypothyroidism.

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

Theoretically, ashwagandha might decrease the levels and clinical effects of CYP1A2 substrates.
In vitro research shows that ashwagandha extract induces CYP1A2 enzymes.

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

Theoretically, ashwagandha might decrease the levels and clinical effects of CYP3A4 substrates.
In vitro research shows that ashwagandha extract induces CYP3A4 enzymes.

Likelihood Possible Evidence D
Serotonergic Drugs

Some animal studies have reported that ashwagandha can enhance serotonergic transmission by altering certain serotonin (5-HT) receptors. However, there is no evidence to suggest that ashwagandha increases the risk of serotonin-related effects, and there have been no published case reports of serotonin syndrome when combined with other serotonergic drugs. Nevertheless, due to the lack of extensive studies on the matter and the fact that ashwagandha appears to affect serotonergic pathways, it would be prudent to exercise caution when combining it with drugs that affect serotonin. [References: - Effects of Withania somnifera (Ashwaga ndha) on Stress and the Stress-Related Neuropsychiatric Disorders Anxiety, Depression, and Insomnia. Curr Neuropharmacol. 2021 Sep 14; 19: 1468–1495. - A Prospective, Randomized Double-Blind, Placebo-Controlled Study of Safety and Efficacy of a High-Concentration Full-Spectrum Extract of Ashwagandha Root in Reducing Stress and Anxiety in Adults. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3573577/]

Likelihood Possible Evidence C
Ashwagandha Root Extract full monograph & interactions

Bioperine 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
Bioperine Black Pepper Fruit Extract full monograph & interactions

L-Arginine Hydrochloride9 drug types · 403 drugs

Ace Inhibitors (Aceis)

Theoretically, concomitant use of L-arginine and ACE inhibitors may increase the risk for hypotension and hyperkalemia.
Combining L-arginine with some antihypertensive drugs, especially ACE inhibitors, seems to have additive vasodilating and blood pressure-lowering effects. Furthermore, ACE inhibitors can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concomitant use of ACE inhibitors with L-arginine may increases the risk of hyperkalemia.

Likelihood Probable Evidence D
Angiotensin Receptor Blockers (Arbs)

Theoretically, concomitant use of L-arginine and ARBs may increase the risk of hypotension and hyperkalemia.
L-arginine increases nitric oxide, which causes vasodilation. Combining L-arginine with ARBs seems to increase L-arginine-induced vasodilation. Furthermore, ARBs can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concomitant use of ARBs with L-arginine may increases the risk of hyperkalemia.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, concomitant use of L-arginine with anticoagulant and antiplatelet drugs might have additive effects and increase the risk of bleeding.
Preliminary research suggests that L-arginine infusions reduce platelet aggregation in humans. The clinical significance of this effect is unclear.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, concomitant use of L-arginine might have additive effects with antidiabetes drugs.
Preliminary clinical research shows that L-arginine decreases blood glucose levels in patients with type 2 diabetes.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, concomitant use of L-arginine and antihypertensive drugs may increase the risk of hypotension.
L-arginine increases nitric oxide, which causes vasodilation. Clinical evidence shows that L-arginine can reduce blood pressure in some individuals with hypertension. Furthermore, combining L-arginine with some antihypertensive drugs seems to have additive vasodilating and blood pressure-lowering effects.

Likelihood Probable Evidence D
Isoproterenol (Isuprel)

Theoretically, concurrent use of isoproterenol and L-arginine might result in additive effects and hypotension.
Preliminary clinical evidence suggests that L-arginine enhances isoproterenol-induced vasodilation in patients with essential hypertension or a family history of essential hypertension.

Likelihood Probable Evidence D
Potassium-Sparing Diuretics

Theoretically concomitant use of potassium-sparing diuretics with L-arginine may increases the risk of hyperkalemia.
Potassium-sparing diuretics can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Theoretically, concurrent use of sildenafil and L-arginine might increase the risk for hypotension.
In vivo, concurrent use of L-arginine and sildenafil has resulted in increased vasodilation. Theoretically, concurrent use might have additive vasodilatory and hypotensive effects. However, in studies evaluating the combined use of L-arginine and sildenafil for erectile dysfunction, hypotension was not reported.

Likelihood Possible Evidence D
Testosterone

Theoretically, concomitant use of L-arginine and testosterone might have additive effects.
In clinical research, L-arginine increases the level of testosterone in male patients with erectile dysfunction. The clinical significance of this finding is unclear.

Likelihood Possible Evidence D
L-Arginine Hydrochloride full monograph & interactions

TestoPlus Fenugreek Seed Extract9 drug types · 389 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, fenugreek might have additive effects when used with anticoagulant or antiplatelet drugs.
Some of the constituents in fenugreek have antiplatelet effects in animal and in vitro research. However, common fenugreek products might not contain sufficient concentrations of these constituents for clinical effects. A clinical study in patients with coronary artery disease or diabetes shows that taking fenugreek seed powder 2.5 grams twice daily for 3 months does not affect platelet aggregation, fibrinolytic activity, or fibrinogen levels .

Likelihood Unlikely Evidence B
Antidiabetes Drugs

Theoretically, fenugreek seed might have additive hypoglycemic effects when used with antidiabetes drugs.
Clinical research shows that fenugreek seed can reduce fasting blood glucose and 2-hour postprandial glucose levels in adults with type 2 diabetes.

Likelihood Probable Evidence B
Clopidogrel (Plavix)

Theoretically, fenugreek seed might alter the clinical effects of clopidogrel by inhibiting its conversion to the active form.
Animal research shows that fenugreek seed 200 mg/kg daily for 14 days increases the maximum serum concentration of clopidogrel by 21%. It is unclear how this affects the pharmacokinetics of the active metabolite of clopidogrel; however, this study found that concomitant use of fenugreek seed and clopidogrel prolonged bleeding time by an additional 11%.

Likelihood Possible Evidence D
Metoprolol (Toprol)

Theoretically, fenugreek seed might have additive hypotensive effects when used with metoprolol.
Animal research shows that fenugreek seed 300 mg/kg daily for 2 weeks decreases systolic and diastolic blood pressure by 9% and 11%, respectively, when administered alone, and by 15% and 22%, respectively, when given with metoprolol 10 mg/kg.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, fenugreek might decrease plasma levels of phenytoin.
Animal research shows that taking fenugreek seeds for 1 week decreases maximum concentrations and the area under the curve of a single dose of phenytoin by 44% and 72%, respectively. This seems to be related to increased clearance. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Theoretically, concurrent use of sildenafil and fenugreek might reduce levels and therapeutic effects of sildenafil.
Animal research shows that taking fenugreek seeds for 1 week reduces maximum concentrations and the area under the curve of a single dose of sildenafil by 27% and 48%, respectively. So far, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Theophylline

Theoretically, fenugreek may reduce the levels and clinical effects of theophylline.
Animal research shows that fenugreek 50 grams daily for 7 days reduces the maximum serum concentration (Cmax) of theophylline by 28% and the area under the plasma drug concentration-time curve (AUC) by 22%.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, fenugreek might have additive effects with warfarin and increase the international normalized ratio (INR).
Some fenugreek constituents have antiplatelet effects, although these might not be present in concentrations that are clinically significant. In one case report, a patient taking warfarin experienced an increased INR when starting to take fenugreek in combination with boldo.

Likelihood Possible Evidence D
Antihypertensive Drugs

Fenugreek may also have an additive effect on blood pressure-lowering medications. Studies on animals have shown that fenugreek seed can decrease both systolic and diastolic blood pressure by up to 22% when combined with metoprolol. Therefore, it is essential to monitor your blood pressure regularly if you are taking fenugreek and metoprolol together or any other antihypertensive drugs.

Likelihood Possible Evidence C
TestoPlus Fenugreek Seed Extract full monograph & interactions

Chrysin9 drug types · 358 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, chrysin might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
In vitro evidence suggests that chrysin might inhibit platelet aggregation.

Likelihood Possible Evidence D
Aromatase Inhibitors

Theoretically, chrysin might increase the effects and adverse effects of aromatase inhibitors.
In vitro research suggests that chrysin might decrease estrogen synthesis by acting as an aromatase (estrogen synthetase) inhibitor..

Likelihood Possible Evidence D
Contraceptive Drugs

Theoretically, chrysin might reduce the efficacy of estrogen-containing contraceptive drugs.
In vitro research suggests that chrysin might have antiestrogenic activity.

Likelihood Possible Evidence D
Diclofenac (Voltaren, Others)

Theoretically, chrysin might increase the effects and adverse effects of diclofenac.
In vitro research suggests that chrysin and its sulfate conjugate inhibit diclofenac metabolism. It is speculated that chrysin and its sulfate conjugate reduce the metabolism of diclofenac by inhibiting cytochrome P450 2C9. This effect has not been reported in humans.

Likelihood Possible Evidence D
Estrogens

Theoretically, chrysin might decrease the effects of estrogen therapy.
In vitro research suggests that chrysin might have antiestrogenic activity.

Likelihood Possible Evidence D
Mephenytoin (Mesantoin)

Theoretically, chrysin might increase the effects and adverse effects of mephenytoin.
In vitro research suggests that chrysin and its sulfate and glucuronide conjugates inhibit S-mephenytoin metabolism. It is speculated that chrysin and its conjugates reduce the metabolism of S-mephenytoin by inhibiting cytochrome P450 2C19. This effect has not been reported in humans.

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

Theoretically, chrysin might increase levels of drugs metabolized by CYP1A2.
In vitro research suggests that chrysin inhibits CYP1A2 isozymes. However, chrysin does not appear to inhibit CYP1A2-dependent caffeine metabolism in animals. Due to chrysin's low bioavailability and rapid metabolism to glucuronide and sulfate conjugates, this interaction is unlikely.

Likelihood Unlikely Evidence D
Glucuronidated Drugs

Theoretically, chrysin might increase the clearance of drugs that are UGT1A1 substrates, thereby reducing their effectiveness.
In vitro research suggests that chrysin might induce UDP-glucuronosyltransferase 1A1 (UGT1A1).

Likelihood Unlikely Evidence D
Testosterone

Theoretically, chrysin might increase the effects and adverse effects of testosterone.
In vitro research suggests that chrysin and its sulfate conjugate inhibit testosterone metabolism. It is speculated that chrysin and its sulfate conjugate reduce the metabolism of testosterone by inhibiting cytochrome P450 3A4. This effect has not been reported in humans.

Likelihood Possible Evidence D
Chrysin full monograph & interactions

Indole-3-Carbinol3 drug types · 294 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, indole-3-carbinol might increase the risk of bleeding when used with antiplatelet or anticoagulant drugs.
In vitro research shows that indole-3-carbinol inhibits platelet aggregation.

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

Theoretically, indole-3-carbinol might increase the metabolism of CYP1A2 substrates and lower serum concentrations.
Animal research shows that indole-3-carbinol induces CYP1A2 enzymes.

Likelihood Possible Evidence D
Estrogens

Indole-3-carbinol might interfere with the effects of estrogen therapy.
Preliminary clinical and in vitro evidence shows that indole-3-carbinol has antiestrogenic activity.

Likelihood Possible Evidence D
Indole-3-Carbinol full monograph & interactions

Diindolylmethane3 drug types · 269 drugs

Diuretic Drugs

Theoretically, diindolylmethane might increase the risk of hyponatremia if used with sodium-depleting diuretics.
Large doses of diindolylmethane (600 mg daily) have been associated with two cases of asymptomatic hyponatremia in clinical research.

Likelihood Possible Evidence B
Estrogens

Theoretically, diindolylmethane might increase or decrease the effects of estrogens.
Diindolylmethane might have mild estrogenic or antiestrogenic effects. Theoretically, large amounts of diindolylmethane might interfere with hormone replacement therapy.

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

Theoretically, diindolylmethane might lower serum levels of CYP1A2 substrates.
In vitro evidence suggests that diindolylmethane can induce CYP1A2. Theoretically, it might increase metabolism of CYP1A2 substrates and lower serum concentrations. This interaction has not been reported in humans.

Likelihood Unlikely Evidence D
Diindolylmethane full monograph & interactions

Tribulus Fruit Extract3 drug types · 259 drugs

Antidiabetes Drugs

Taking tribulus with antidiabetes drugs might increase the risk of hypoglycemia.
Clinical research shows that Tribulus can lower blood glucose levels in adults with type 2 diabetes who are taking antidiabetes medications.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, taking tribulus with antihypertensive drugs might increase the risk of hypotension.
Animal research shows that tribulus can lower blood pressure by inhibiting angiotensin-converting enzyme (ACE). Tribulus has also demonstrated hypotensive effects in pre-hypertensive adults.

Likelihood Possible Evidence D
Lithium

Theoretically, tribulus might increase the levels and clinical effects of lithium.
Tribulus is thought to have diuretic properties. Due to these potential diuretic effects, tribulus might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Probable Evidence D
Tribulus Fruit Extract full monograph & interactions

Tongkat Ali Root Extract5 drug types · 248 drugs

Propranolol (Inderal)

Eurycoma longifolia can reduce the levels and clinical effects of propranolol.
A small clinical study in healthy persons shows that taking a single dose of a water-based Eurycoma longifolia extract 200 mg, in combination with a single dose of propranolol 80 mg, reduces the propranolol area under the curve (AUC) by 29%, reduces the peak concentration by 42%, and increases time to peak concentration by 86% when compared with control. Since the elimination half-life of propranolol did not change, it seems that Eurycoma longifolia alters the kinetics of propranolol by decreasing its absorption in the gut, and not by altering its metabolism. It is not known if separating administration will prevent this interaction.

Likelihood Probable Evidence A
Cytochrome P450 1A2 (Cyp1A2) Substrates

Theoretically, Eurycoma longifolia might increase levels CYP1A2 substrates.
In vitro research suggests that methanolic Eurycoma longifolia root extract weakly inhibits CYP1A2 enzymes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2A6 (Cyp2A6) Substrates

Theoretically, Eurycoma longifolia might increase levels of CYP2A6 substrates.
In vitro research suggests that methanolic Eurycoma longifolia root extract weakly inhibits CYP2A6 enzymes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2C19 (Cyp2C19) Substrates

Theoretically, Eurycoma longifolia might increase levels of CYP2C19 substrates.
In vitro research suggests that methanolic Eurycoma longifolia root extract weakly inhibits CYP2C19 enzymes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Testosterone

Theoretically, Eurycoma longifolia may further increase levels of testosterone.
A clinical study in aging males with testosterone levels below 300 ng/dL shows that taking a specific water extract of Eurycoma longifolia roots (Physta; Biotropics Malaysia) 100-200 mg daily with breakfast for 12 weeks increases total testosterone levels by 8% to 11% when compared with placebo. It is unclear whether this increase would occur in individuals with normal testosterone levels.

Likelihood Possible Evidence D
Tongkat Ali Root Extract full monograph & interactions

L-Citrulline2 drug types · 178 drugs

Antihypertensive Drugs

Theoretically, concomitant use of L-citrulline with antihypertensive drugs might have additive effects and increase the chance of hypotension.
L-citrulline is converted to L-arginine, which can increase nitric oxide and cause vasodilation. However, a meta-analysis of 5 small clinical studies suggests that taking L-citrulline 3-6 grams daily for 1-8 weeks does not lower blood pressure when compared with control.

Likelihood Possible Evidence B
Phosphodiesterase-5 Inhibitors

Theoretically, concurrent use of phosphodiesterase-5 (PDE-5) inhibitors and L-citrulline might result in additive vasodilation.
L-citrulline is converted to L-arginine, which can increase nitric oxide and cause vasodilation. Theoretically, taking L-arginine with PDE-5 inhibitors might have additive vasodilatory and hypotensive effects. However, in studies evaluating the combined use of L-arginine and sildenafil for erectile dysfunction, hypotension was not reported.

Likelihood Possible Evidence D
L-Citrulline full monograph & interactions

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
Saw Palmetto Berry Extract full monograph & interactions

Stinging Nettle Leaf Extract4 drug types · 164 drugs

Antidiabetes Drugs

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

Likelihood Possible Evidence B
Diuretic Drugs

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

Likelihood Possible Evidence D
Lithium

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

Likelihood Possible Evidence D
Warfarin (Coumadin)

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

Likelihood Possible Evidence D
Stinging Nettle Leaf Extract full monograph & interactions

Cissus Leaf Extract1 drug type · 86 drugs

Antidiabetes Drugs

Theoretically, Cissus quadrangularis might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Small clinical studies suggest that Cissus quadrangularis might reduce fasting blood glucose in individuals with overweight or obesity.

Likelihood Possible Evidence D
Cissus Leaf Extract full monograph & interactions

Pumpkin Seed Oil, Extra Virgin1 drug type · 1 drug

Lithium

Pumpkin might reduce excretion and increase levels of lithium.
Pumpkin is thought to have diuretic properties. Theoretically, this might reduce excretion and increase levels of lithium. The dose of lithium might need to be decreased.

Likelihood Probable Evidence D
Pumpkin Seed Oil, Extra Virgin full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Testosterone Power, from the product label.

Nature's Truth

See all Nature's Truth products
Name
Nature's Truth LLC
City
Ronkonkoma
State
NY
ZipCode
11779
Phone Number
1-844-544-1030
Web Address
NaturesTruth.com
Pharmacist Counseling Corner

Testosterone Power by Nature's Truth: Common Questions

Does Testosterone Power by Nature's Truth interact with any medications?
Yes. Based on its ingredients, Testosterone Power has a known interaction with 1,518 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Testosterone Power contains 15 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.
Does this product work for erectile dysfunction?
Several ingredients—Tribulus Fruit, Fenugreek Seed, and Tongkat Ali—are rated possibly effective for sexual dysfunction. L-Arginine and L-Citrulline improve blood flow, which is how they're thought to help. That said, evidence varies, and this supplement isn't a replacement for talking to your doctor about sexual health.
Can I take this if I'm on blood pressure medication?
Not without checking first. L-Citrulline, L-Arginine, Ashwagandha, and Tribulus can all lower blood pressure, and combining them with your medication could cause dangerously low readings. Talk to your pharmacist about your specific blood pressure drug before starting.
Is it safe to take while breastfeeding?
Safety data are not established for most ingredients in this formula while breastfeeding. Although Fenugreek is traditionally used to boost milk supply, it hasn't been thoroughly tested in combination with other herbs here. Discuss this product with your doctor or lactation consultant before use.
What are the most common side effects?
Gastrointestinal discomfort—nausea, diarrhea, and bloating—are the most frequently reported. Headache and heartburn also occur. These are usually mild and often don't require stopping the supplement, but if they persist, talk to your pharmacist.
Should I avoid this if I'm diabetic?
If you take diabetes medication, yes—check with your pharmacist first. Ashwagandha, Stinging Nettle, Tribulus, Fenugreek, and Cissus Leaf can all lower blood sugar, and combining them with your medicine might cause your glucose to drop too low.
Does this contain any fillers or binders?
Yes. Beyond the 15 active ingredients, the softgel contains gelatin capsule, glycerin, beeswax, lecithin, and colorants like carmine, turmeric oleoresin, and titanium dioxide. If you have sensitivities to any of these, check the label or ask your pharmacist.

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

Not sure if Testosterone Power is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

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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.

Testosterone Power label
Go deeper

The Full Monographs Behind Testosterone Power’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

Pumpkin

Interacts with 1 drug

Pumpkin is a nutritious squash, and its seeds and seed oil are the parts most often used as supplements, mainly for urinary and prostate symptoms. The evidence for these uses is limited and...

Read the full Pumpkin 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

Ashwagandha

Interacts with 1,372 drugs

Ashwagandha is an Ayurvedic herb most often taken to help with stress, anxiety, and sleep, and some small studies suggest it may help, though the evidence is still limited. It is generally w...

Read the full Ashwagandha 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

Tribulus

Interacts with 259 drugs

Tribulus is a plant supplement most often marketed to boost libido, testosterone, and athletic performance, but the human evidence behind these claims is weak and inconsistent. It is general...

Read the full Tribulus monograph → Herb & supplement monograph

Eurycoma Longifolia

Interacts with 248 drugs

Eurycoma longifolia (tongkat ali) is a Southeast Asian herb most popular for supporting testosterone, libido, and male fertility, with some small human studies suggesting possible benefits....

Read the full Eurycoma Longifolia monograph → Herb & supplement monograph

Cissus Quadrangularis

Interacts with 86 drugs

Cissus quadrangularis is a traditional vine used mainly for bone health, joint pain, and weight management. Most of the supporting evidence comes from animal studies and a small number of hu...

Read the full Cissus Quadrangularis monograph → Herb & supplement monograph

Fenugreek

Interacts with 389 drugs

Fenugreek is a common kitchen spice that is also taken as a supplement, mainly for blood sugar, cholesterol, and to support breast milk production. Some early research is encouraging for blo...

Read the full Fenugreek monograph → Herb & supplement monograph

Diindolylmethane

Interacts with 269 drugs

Diindolylmethane (DIM) is a compound made when your body digests cruciferous vegetables, and it is sold as a supplement mainly for hormone balance and cancer prevention. Although early lab s...

Read the full Diindolylmethane monograph → Herb & supplement monograph

Indole-3-carbinol

Interacts with 294 drugs

Indole-3-carbinol (I3C) is a compound formed when you eat cruciferous vegetables like broccoli and cabbage, and it is sold as a supplement mainly for hormone-related and cell-protective effe...

Read the full Indole-3-carbinol monograph → Herb & supplement monograph

Chrysin

Interacts with 358 drugs

Chrysin is a plant flavonoid sold mainly as a bodybuilding supplement claimed to raise testosterone or block estrogen, but human studies have not shown these benefits, largely because the bo...

Read the full Chrysin monograph → Herb & supplement monograph

L-citrulline

Interacts with 178 drugs

L-citrulline is an amino acid that the body turns into L-arginine to help make nitric oxide, which relaxes blood vessels and may improve blood flow. It is popular for exercise performance an...

Read the full L-citrulline monograph → Herb & supplement monograph

L-arginine

Interacts with 403 drugs

L-arginine is an amino acid that the body uses to make nitric oxide, a substance that helps blood vessels relax and widen. It is popularly used for blood pressure, erectile dysfunction, and...

Read the full L-arginine monograph →
Sources

Sources & How We Checked

Testosterone Power'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 280 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.

L-citrulline 8 references
  1. Cheng JW, Balwin SN. L-arginine in the management of cardiovascular diseases. Ann Pharmacother 2001;35:755-64. PubMed
  2. Schwedhelm E, Maas R, Freese R, et al. Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolism. Br J Clin Pharmacol 2008;65:51-9. PubMed
  3. Romero MJ, Platt DH, Caldwell RB, Caldwell RW. Therapeutic use of citrulline in cardiovascular disease. Cardiovasc Drug Rev 2006;24:275-90. PubMed
  4. Balderas-Munoz K, Castillo-Martínez L, Orea-Tejeda A, et al. Improvement of ventricular function in systolic heart failure patients with oral L-citrulline supplementation. Cardiol J 2012;19:612-7. PubMed
  5. Sharif Kashani B, Tahmaseb Pour P, Malekmohammad M, et al. Oral l-citrulline malate in patients with idiopathic pulmonary arterial hypertension and Eisenmenger Syndrome: a clinical trial. J Cardiol 2014;64:231-5. PubMed
  6. Pérez-Guisado J, Jakeman PM. Citrulline malate enhances athletic anaerobic performance and relieves muscle soreness. J Strength Cond Res 2010;24:1215-22. PubMed
  7. Mirenayat MS, Moradi S, Mohammadi H, Rouhani MH. Effect of L-citrulline supplementation on blood pressure: a systematic review and meta-analysis of clinical trials. Curr Hypertens Rep. 2018;20(11):98. PubMed
  8. Xu Z, Liu C, Liu S, Zhou Z. Comparison of efficacy and safety of daily oral L-arginine and PDE5Is alone or combination in treating erectile dysfunction: A systematic review and meta-analysis of randomised controlled trials. Andrologia. 2021:e14007. PubMed

See these in context on the L-citrulline monograph →

Saw Palmetto 22 references
  1. Wilt TJ, Ishani A, Stark G, et al. Saw palmetto extracts for treatment of benign prostatic hyperplasia: a systematic review. JAMA 1998;280:1604-9. PubMed
  2. Carraro JC, Raynaud JP, Koch G, et al. Comparison of phytotherapy (Permixon) with finasteride in the treatment of benign prostate hyperplasia: a randomized international study of 1,098 patients. Prostate 1996;29:231-40. DOI
  3. Di Silverio F, D'Eramo G, Lubrano C, et al. Evidence that Serenoa repens extract displays an antiestrogenic activity in prostatic tissue of benign prostatic hypertrophy patients. Eur Urol 1992;21:309-14. PubMed
  4. Stepanov VN, Siniakova LA, Sarrazin B, Raynaud JP. Efficacy and tolerability of the lipidosterolic extract of Serenoa repens (Permixon) in benign prostatic hyperplasia: a double-blind comparison of two dosage regimens. Adv Ther 1999;16:231-41.
  5. Cheema P, El-Mefty O, Jazieh AR. Intraoperative haemorrhage associated with the use of extract of Saw Palmetto herb: a case report and review of literature. J Intern Med 2001;250:167-9. PubMed
  6. Jibrin I, Erinle A, Saidi A, Aliyu ZY. Saw palmetto-induced pancreatitis. South Med J 2006;99:611-2. PubMed
  7. Prager N, Bickett K, French N, Marcovici G. A randomized, double-blind, placebo-controlled trial to determine the effectiveness of botanically derived inhibitors of 5-alpha-reductase in the treatment of androgenetic alopecia. J Altern Complement Med 2002
  8. Avins AL, Bent S, Staccone S, et al. A detailed safety assessment of a saw palmetto extract. Complement Ther Med 2008;16:147-54. PubMed
  9. Morgia, G., Mucciardi, G., Gali, A., Madonia, M., Marchese, F., Di, Benedetto A., Romano, G., Bonvissuto, G., Castelli, T., Macchione, L., and Magno, C. Treatment of chronic prostatitis/chronic pelvic pain syndrome category IIIA with Serenoa repens plus
  10. Aliaev, IuG, Vinarov, A. Z., Lokshin, K. L., and Spivak, L. G. [Efficiency and safety of prostamol-Uno in patients with chronic abacterial prostatitis]. Urologiia. 2006;(1):47-50.
  11. Agbabiaka, T. B., Pittler, M. H., Wider, B., and Ernst, E. Serenoa repens (saw palmetto): a systematic review of adverse events. Drug Saf 2009;32(8):637-647. PubMed
  12. Wargo, K. A., Allman, E., and Ibrahim, F. A possible case of saw palmetto-induced pancreatitis. South.Med.J. 2010;103(7):683-685. PubMed
  13. Lapi, F., Gallo, E., Giocaliere, E., Vietri, M., Baronti, R., Pieraccini, G., Tafi, A., Menniti-Ippolito, F., Mugelli, A., Firenzuoli, F., and Vannacci, A. Acute liver damage due to Serenoa repens: a case report. Br.J.Clin.Pharmacol. 2010;69(5):558-560.
  14. Mantovani, F. Serenoa repens in benign prostatic hypertrophy: analysis of 2 Italian studies. Minerva Urol.Nefrol. 2010;62(4):335-340.
  15. Hanaka, M., Yoshii, C., Yatera, K., Ito, C., Chojin, Y., Nagata, S., Yamasaki, K., Nishida, C., Kawanami, T., Kawanami, Y., Ishimoto, H., and Mukae, H. [A case of rhabdomyolysis caused by saw palmetto of healthy foods]. J.UOEH. 6-1-2012;34(2):193-199. PubMed
  16. Miroddi, M., Carni, A., Mannucci, C., Moleti, M., Navarra, M., and Calapai, G. Hot flashes in a young girl: a wake-up call concerning Serenoa repens use in children. Pediatrics 2012;130(5):e1374-e1376.
  17. Braeckman J. The extract of Serenoa repens in the treatment of benign prostatic hyperplasia: a multicenter open study. Current Therapeutic Research 1994;55(7):776-785. DOI
  18. Jipescu D, Patel A, Bohra H, Pientka A. Rare case of saw palmetto induced heart block. JACC 2017;69(11) supplement:2310.
  19. Morabito P, Miroddi M, Giovinazzo S, Spina E, Calapai G. Serenoa repens as an endocrine disruptor in a 10-year-Old young girl: a new case report. Pharmacology. 2015;96(1-2):41-3. doi: 10.1159/000431327.
  20. Gammoudi R, Ameur K, Ouni B, et al. Fixed drug eruption to Serenoa repens: first case report and consideration of the use of herbal medicine. Dermatol Ther 2020 Aug 29:e14247.
  21. Paulis G, Paulis A, Perletti G. Serenoa repens and its effects on male sexual function. A systematic review and meta-analysis of clinical trials. Arch Ital Urol Androl 2021;93(4):475-480. PubMed
  22. Venkateswaran S, Declet-Bauzo R, Shodeinde M, Gilford P. Postoperative Retroperitoneal Hematoma: A Case of Saw Palmetto and the Importance of Primary Care Intervention. HCA Healthc J Med 2020;1(5):279-282. PubMed

See these in context on the Saw Palmetto monograph →

L-arginine 66 references
  1. Sapienza MA, Kharitonov SA, Horvath I, et al. Effect of inhaled L-arginine on exhaled nitric oxide in normal and asthmatic subjects. Thorax 1998;53:172-5.
  2. Clarkson P, Adams MR, Powe AJ, et al. Oral L-arginine improves endothelium-dependent dilation in hypercholesterolemic young adults. J Clin Invest 1996;97:1989-94. PubMed
  3. Tenenbaum A, Fisman EZ, Motro M. L-arginine: Rediscovery in progress. Cardiology 1998;90:153-9.
  4. Brittenden J, Park KGM, Heys SD, et al. L-Arginine stimulates host defenses in patients with breast cancer. Surgery 1994;115:205-12.
  5. Korting GE, Smith SD, Wheeler MA, et al. A randomized double-blind trial of oral L-arginine for treatment of interstitial cystitis. J Urol 1999;161:558-65. DOI
  6. Rector TS, Bank AJ, Mullen KA, et al. Randomized, double-blind, placebo-controlled study of supplemental oral L-arginine in patients with heart failure. Circulation 1996;93:2135-41.
  7. Siani A, Pagano E, Iacone R, et al. Blood pressure and metabolic changes during dietary L-arginine supplementation in humans. Am J Hypertens 2000;13:547-51. PubMed
  8. Cheng JW, Balwin SN. L-arginine in the management of cardiovascular diseases. Ann Pharmacother 2001;35:755-64. PubMed
  9. Wallace AW, Tom WL. Interaction of L-arginine and phosphodiesterase inhibitors in vasodilation of the porcine internal mammary artery. Anesth Analg 2000;90:840-6. DOI
  10. Huynh NT, Tayek JA. Oral arginine reduces systemic blood pressure in type 2 diabetes: its potential role in nitric oxide generation. J Am Coll Nutr 2002;21:422-7.. PubMed
  11. Staff AC, Berge L, Haugen G, et al. Dietary supplementation with L-arginine or placebo in women with pre-eclampsia. Acta Obstet Gynecol Scand 2004;83:103-7.
  12. Resnick DJ, Softness B, Murphy AR, et al. Case report of an anaphylactoid reaction to arginine. Ann Allergy Asthma Immunol 2002;88:67-8. PubMed
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Indole-3-carbinol 9 references
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Chrysin 23 references
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Tribulus 10 references
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Eurycoma Longifolia 4 references
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Pumpkin 5 references
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Cissus Quadrangularis 5 references
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Fenugreek 30 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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