Interactions on record — worth a quick check against your medications. Based on 9 of 10 ingredients. Check your meds →
Dietary supplement

Royal-T Ingredients & Drug Interactions

by Royal Sport

Royal-T label
See full label image
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 Royal-T 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

Royal-T is a dietary supplement by Royal Sport with 10 active ingredients. Its ingredients are commonly taken for blood sugar control, boosting breast milk supply, high cholesterol.Based on those ingredients, 1,461 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Rhodiola (Rhodiola rosea) root extract, Black Pepper (Piper nigrum) fruit extract, Fenugreek (Trigonella foenum-graecum) seed extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Royal-T by Royal Sport

Ask about any prescription or over-the-counter medication and we check it for interactions with Royal-T by Royal Sport — and tell you which ingredient is responsible.

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Computed from our clinical databases

HelloPharmacist Scorecard of Royal-T by Royal Sport

Four independent checks of what is known — a summary of the available information, not a grade of the product itself.

Evidence for Intended Use
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
Not assessable

The stated purpose hasn't been mapped to our evidence data yet.

Why this rating?
  • We haven't mapped this product's purpose to our evidence data yet — it'll be graded on the next content refresh.
Ingredient Transparency
Low

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

Why this rating?
  • The label discloses an exact amount for 0 of its 10 active ingredients.
  • “Royal-T Testosterone & Virility Matrix (Combination)” is a proprietary blend — the label gives one combined amount (1,183 mg) without saying how much of each component you get.
  • “Royal-T Mental Focus & Shield Matrix (Combination)” is a proprietary blend — the label gives one combined amount (171 mg) without saying how much of each component you get.
Known Interaction Concern
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 9 of the 9 matched ingredients can interact with medications — Tribulus, Toothed Clubmoss, Stinging Nettle, Fenugreek, Black Pepper, 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: 1,462 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.
Safety Information
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 9 of the 9 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 9 of 9.
  • General safety write-ups exist for 9 of 9.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

HelloPharmacist summaryFormula with limited ingredient disclosure with no assessable stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

Assessment coverage: 9 of 10 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 23, 2018.

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 Royal-T, straight from the product label.

Brand Royal Sport
Barcode (UPC) 810390028801
Net contents 120 Capsule(s)
Market status Off market
Date entered into DSLD Feb 23, 2018
DSLD ID 83194
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult Male (18-50 Years)
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 Royal-T by Royal Sport, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
2 Capsule(s)
Maximum serving Sizes:
2 Capsule(s)
Servings per container
60
UPC/BARCODE
810390028801
IngredientAmount% DV
D-Aspartic Acid0 NP--
Fenugreek (Trigonella foenum-graecum) seed extract0 NP--
Rhodiola (Rhodiola rosea) root extract0 NP--
Stinging Nettle (Urtica dioica) root extract0 NP--
Eurycoma longifolia root extract0 NP--
3,3'-Diindolylmethane0 NP--
Saw Palmetto (Serenoa repens) fruit extract0 NP--
Tribulus (Tribulus terrestris) fruit extract0 NP--
Royal-T Testosterone & Virility Matrix (Combination)1183 mg--
Royal-T Mental Focus & Shield Matrix (Combination)171 mg--
Toothed Clubmoss (Huperzia serrata) leaf extract0 NP--
Black Pepper (Piper nigrum) fruit extract0 NP--

Other ingredients: Gelatin, Magnesium Stearate, Silicon Dioxide, Titanium Dioxide, FD&C Red #3, FD&C Blue #1

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.
General Statements

Testosterone support Estrogen modulation Virility Cognitive & stress support

Facebook RoyalSportLTD Twitter @RoyalSportLTD Instagram RoyalSportLTD

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Suggested Use: On non-training days, take 1 serving (2 capsules) in the morning with or without food and one serving in the evening with or without food. On training days, both servings may be consumed 30 minutes prior to training. Do not use for more than 8 weeks without discontinuing use for 4 weeks. Do not exceed 4 capsules in a 24 hour period.

Precautions

Do not use for more than 8 weeks without discontinuing use for 4 weeks. Do not exceed 4 capsules in a 24 hour period. Warning: This product is only intended to be consumed by healthy, adult men, 18 years of age or older.

Not for use by women, especially those who are pregnant or nursing.

Do not use this product if you have any serious medical condition.

Before using this product, consult with a licensed, qualified, health care professional, including but not limited to, if you suspect you have or have been treated for, diagnosed with or have a family history of any medical condition, or if you are using any prescription or over the counter medication.

Immediately discontinue use and contact a medical doctor if you experience any adverse reaction to this product. Discontinue use 2 weeks prior to surgery. Do not exceed recommendations for suggested use. Use only as directed. Do not use if safety seal is broken or missing.

Keep out of reach of children.

Formula

Warning: This product is only intended to be consumed by healthy, adult men, 18 years of age or older.

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.

Brand IP Statement(s)

Royal Sport LTD and Royal-T are trademarks of and distributed by: Nutrabolt

General

103905

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

See for yourself

Royal-T by Royal Sport label

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

Royal-T 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 Royal-T by Royal Sport

These are the 10 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Royal-T Testosterone & Virility Matrix (Combination)

1183 mg per serving

Other (inactive) ingredients: Gelatin, Magnesium Stearate, Silicon Dioxide, Titanium Dioxide, FD&C Red #3, FD&C Blue #1. These complete the product’s ingredient list but are not active constituents.

Interaction report

Royal-T by Royal Sport Drug Interactions

Royal-T contains 10 ingredients, and 9 of them have known drug interactions. Altogether they interact with 1,461 medications. Here’s the picture, then you can look up your own drug.

Want to check YOUR meds against Royal-T?

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
1,461Drugs
1,329 Moderate 132 Minor

Ingredients driving the most interactions

Rhodiola (Rhodiola rosea) root extract 1,271
Black Pepper (Piper nigrum) fruit extract 1,019
Fenugreek (Trigonella foenum-graecum) seed extract 389
3,3'-Diindolylmethane 269
Tribulus (Tribulus terrestris) fruit extract 259

Individual Drug Interactions

The ingredients in Royal-T interact with 1,461 drugs. Click any drug to see the details.

9 of the 10 ingredients in Royal-T interact with drugs. Each result below shows which ingredient is responsible. Rhodiola (Rhodiola rosea) root extract Black Pepper (Piper nigrum) fruit extract Fenugreek (Trigonella foenum-graecum) seed extract 3,3'-Diindolylmethane Tribulus (Tribulus terrestris) fruit extract Eurycoma longifolia root extract Toothed Clubmoss (Huperzia serrata) leaf extract Saw Palmetto (Serenoa repens) fruit extract Stinging Nettle (Urtica dioica) root extract

Each ingredient & the kinds of drugs it affects

For each ingredient in Royal-T 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.

Rhodiola (Rhodiola rosea) root extract10 drug types · 1,271 drugs

Antidiabetes Drugs

Theoretically, taking rhodiola with antidiabetes drugs might increase the risk of hypoglycemia.
In vitro and animal research shows that rhodiola extract can decrease blood glucose due to alpha-glucosidase activity.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, taking rhodiola with antihypertensive drugs might increase the risk of hypotension.
In vitro and animal research shows that rhodiola extract inhibits angiotensin-converting enzyme (ACE) and might lower blood pressure.

Likelihood Possible Evidence D
Cytochrome P450 2C9 (Cyp2C9) Substrates

Theoretically, rhodiola might increase levels of drugs metabolized by CYP2C9.
In vitro research shows that rhodiola inhibits CYP2C9. This effect is highly variable and appears to be dependent on the rhodiola product studied. Also, a clinical study in healthy young males found that taking rhodiola extract 290 mg daily for 14 days reduces the metabolism of losartan, a CYP2C9 substrate, by 21% after 4 hours.

Likelihood Possible Evidence B
Immunosuppressants

Theoretically, rhodiola use might interfere with immunosuppressive therapy.
In vitro and animal research show that rhodiola has immunostimulatory effects.

Likelihood Possible Evidence D
Losartan (Cozaar)

Rhodiola might increase the levels and adverse effects of losartan.
A clinical study in healthy young males found that taking rhodiola extract 290 mg daily for 14 days reduces the metabolism of losartan, a CYP2C9 substrate, by 21% after 4 hours.

Likelihood Probable Evidence B
P-Glycoprotein Substrates

Theoretically, rhodiola might increase levels of P-glycoprotein substrates.
In vitro research shows that rhodiola inhibits P-glycoprotein. Theoretically, using rhodiola with P-glycoprotein substrates might increase drug levels and potentially increase the risk of adverse effects.

Likelihood Possible Evidence D
Antidepressant Drugs

Theoretically, rhodiola might increase the risk of adverse effects when taken with antidepressants.
A review of adverse event reports in Poland identified cases of tachyarrhythmias, myalgia, arthralgia, gum pain, restless leg syndrome, swallowing disorders, and changes in consciousness when rhodiola was taken in combination with paroxetine, escitalopram, fluoxetine, sertraline, trazodone, and/or duloxetine.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, rhodiola might increase the risk of adverse effects when taken with CNS depressants.
A review of adverse event reports in Poland identified cases of excessive sedation, myoclonus, hypotension, and hallucinations when rhodiola was taken with haloperidol, diazepam, or alprazolam.

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

Theoretically, rhodiola might increase levels of drugs metabolized by CYP1A2.
In vitro research shows that rhodiola inhibits CYP1A2. This effect is highly variable and appears to be dependent on the rhodiola product studied. However, a clinical study in healthy young males found that taking rhodiola extract 290 mg daily for 14 days does not inhibit the metabolism of caffeine, a CYP1A2 substrate.

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

Theoretically, rhodiola might increase levels of drugs metabolized by CYP3A4.
In vitro research shows that rhodiola inhibits CYP3A4. This effect is highly variable and appears to be dependent on the rhodiola product studied. However, a clinical study in healthy young males found that taking rhodiola extract 290 mg daily for 14 days does not inhibit the metabolism of midazolam, a CYP3A4 substrate.

Likelihood Possible Evidence B
Rhodiola (Rhodiola rosea) root extract full monograph & interactions

Black Pepper (Piper nigrum) fruit extract17 drug types · 1,019 drugs

Anticoagulant/Antiplatelet Drugs

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

Likelihood Possible Evidence D
Antidiabetes Drugs

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

Likelihood Possible Evidence D
Atorvastatin (Lipitor)

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

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

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

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

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

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

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

Likelihood Possible Evidence D
Lithium

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

Likelihood Probable Evidence D
Nevirapine (Viramune)

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

Likelihood Probable Evidence D
P-Glycoprotein Substrates

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

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

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

Likelihood Possible Evidence D
Phenytoin (Dilantin)

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

Likelihood Possible Evidence B
Propranolol (Inderal)

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

Likelihood Possible Evidence B
Rifampin (Rifadin)

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

Likelihood Possible Evidence B
Theophylline

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

Likelihood Possible Evidence D
Amoxicillin (Amoxil, Trimox)

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

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

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

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

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

Likelihood Possible Evidence D
Black Pepper (Piper nigrum) fruit extract full monograph & interactions

Fenugreek (Trigonella foenum-graecum) 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
Fenugreek (Trigonella foenum-graecum) seed extract full monograph & interactions

3,3'-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
3,3'-Diindolylmethane full monograph & interactions

Tribulus (Tribulus terrestris) 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 (Tribulus terrestris) fruit extract full monograph & interactions

Eurycoma longifolia 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
Eurycoma longifolia root extract full monograph & interactions

Toothed Clubmoss (Huperzia serrata) leaf extract2 drug types · 219 drugs

Anticholinergic Drugs

In animal models, toothed clubmoss and huperzine A, an active constituent of toothed clubmoss, reversed cognitive deficits induced by scopolamine. Theoretically, concurrent use of anticholinergic drugs and toothed clubmoss might decrease the effectiveness of toothed clubmoss or the anticholinergic drug.
Some anticholinergic drugs include atropine, benztropine (Cogentin), biperiden (Akineton), procyclidine (Kemadrin), and trihexyphenidyl (Artane).

Likelihood Possible Evidence D
Cholinergic Drugs

Huperzine A, a constituent of toothed clubmoss, has demonstrated acetylcholinesterase inhibitory properties. Theoretically, concurrent use of toothed clubmoss with cholinergic drugs might have additive effects and increase the risk of cholinergic side effects.
Cholinergic drugs include bethanechol (Urecholine), donepezil (Aricept), echothiophate (Phospholine Iodide), edrophonium (Enlon, Reversol, Tensilon), neostigmine (Prostigmin), physostigmine (Antilirium), pyridostigmine (Mestinon, Regonol), succinylcholine (Anectine, Quelicin), and tacrine (Cognex).

Likelihood Possible Evidence D
Toothed Clubmoss (Huperzia serrata) leaf extract full monograph & interactions

Saw Palmetto (Serenoa repens) fruit 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 (Serenoa repens) fruit extract full monograph & interactions

Stinging Nettle (Urtica dioica) root extract4 drug types · 164 drugs

Antidiabetes Drugs

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

Likelihood Possible Evidence B
Diuretic Drugs

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

Likelihood Possible Evidence D
Lithium

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

Likelihood Possible Evidence D
Warfarin (Coumadin)

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

Likelihood Possible Evidence D
Stinging Nettle (Urtica dioica) root extract full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Royal-T, from the product label.

Royal Sport

See all Royal Sport products
Name
Nutrabolt
Street Address
3891 S. Traditions Dr.
City
Bryan
State
TX
ZipCode
77807
Phone Number
1-800-287-6458
Web Address
www.RoyalSportLTD.com
Pharmacist Counseling Corner

Royal-T by Royal Sport: Common Questions

Does Royal-T by Royal Sport interact with any medications?
Yes. Based on its ingredients, Royal-T has a known interaction with 1,461 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Royal-T contains 10 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.

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

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

Royal-T label
Go deeper

The Full Monographs Behind Royal-T’s Ingredients

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

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

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

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

Rhodiola

Interacts with 1,271 drugs

Rhodiola is an herb traditionally used to fight fatigue and help the body cope with stress. Some small studies suggest it may modestly reduce fatigue and improve mood, but the evidence is li...

Read the full Rhodiola 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

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

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

Toothed Clubmoss

Interacts with 219 drugs

Toothed Clubmoss is a moss-like plant best known as the natural source of huperzine A, a compound studied mainly for memory and Alzheimer's disease. Some early research is promising, but the...

Read the full Toothed Clubmoss monograph → 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 →
Sources

Sources & How We Checked

Royal-T'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 148 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.

Fenugreek 30 references
  1. Madar Z, Thorne R. Dietary fiber. Prog Food Nutr Sci 1987;11:153-74.
  2. Sharma RD, Raghuram TC, Rao NS. Effect of fenugreek seeds on blood glucose and serum lipids in type I diabetes. Eur J Clin Nutr 1990;44:301-6.
  3. Patil SP, Niphadkar PV, Bapat MM. Allergy to fenugreek (Trigonella foenum graecum). Ann Allergy Asthma Immunol 1997;78:297-300. PubMed
  4. Lambert J, Cormier J. Potential interaction between warfarin and boldo-fenugreek. Pharmacotherapy 2001;21:509-12. PubMed
  5. Bordia A, Verma SK, Srivastava KC. Effect of ginger (Zingiber officinale Rosc.) and fenugreek (Trigonella foenumgraecum L.) on blood lipids, blood sugar and platelet aggregation in patients with coronary artery disease. Prostaglandins Leukot Essent Fatty PubMed
  6. Yalcin SS, Tekinalp G, Ozalp I. Peculiar odor of traditional food and maple syrup urine disease. Pediatr Int 1999;41:108-9. PubMed
  7. Sewell AC, Mosandl A, Bohles H. False diagnosis of maple syrup urine disease owing to ingestion of herbal tea. N Engl J Med 1999;341:769.. PubMed
  8. Abdo MS, al-Kafawi AA. Experimental studies on the effect of Trigonella foenum-graecum (abstract). Planta Med 1969;17:14-8.
  9. Gupta A, Gupta R, Lal B. Effect of Trigonella foenum-graecum (fenugreek) seeds on glycaemic control and insulin resistance in type 2 diabetes mellitus: a double blind placebo controlled study. J Assoc Physicians India 2001;49:1057-61.
  10. Gabay MP. Galactogogues: medications that induce lactation. J Hum Lact 2002;18:274-9. PubMed
  11. Chevassus H, Gaillard JB, Farret A, et al. A fenugreek seed extract selectively reduces spontaneous fat intake in overweight subjects. Eur J Clin Pharmacol 2010;66(5):449-55. PubMed
  12. Turkyilmaz C, Onal E, Hirfanoglu IM, et al. The effect of galactagogue herbal tea on breast milk production and short-term catch-up of birth weight in the first week of life. J Altern Complement Med 2011;17(2):139-42. PubMed
  13. Swafford S, Berens P. Effect of fenugreek on breast milk volume. Abstract presented at: 5th International Meeting of the Academy of Breastfeeding Medicine; September 11-13,2000, Tucson, Arizona.
  14. Abdel-Barry, J. A., Abdel-Hassan, I. A., Jawad, A. M., and al Hakiem, M. H. Hypoglycaemic effect of aqueous extract of the leaves of Trigonella foenum-graecum in healthy volunteers. East Mediterr.Health J 2000;6(1):83-88. DOI
  15. Parvizpur, A., Ahmadiani, A., and Kamalinejad, M. Probable role of spinal purinoceptors in the analgesic effect of Trigonella foenum (TFG) leaves extract. J Ethnopharmacol 3-8-2006;104(1-2):108-112. PubMed
  16. Mora, A., Herrrera, A., Lopez, C., Dahbi, G., Mamani, R., Pita, J. M., Alonso, M. P., Llovo, J., Bernardez, M. I., Blanco, J. E., Blanco, M., and Blanco, J. Characteristics of the Shiga-toxin-producing enteroaggregative Escherichia coli O104:H4 German ou
  17. Blanco, J. [Stx2a-producing enteroaggregative Escherichia coli O104:H4-ST678. Microbiological diagnostic already, for this and other STEC/VTEC serotypes!]. Enferm.Infecc.Microbiol.Clin. 2012;30(2):84-89.
  18. Beutin, L. and Martin, A. Outbreak of Shiga toxin-producing Escherichia coli (STEC) O104:H4 infection in Germany causes a paradigm shift with regard to human pathogenicity of STEC strains. J Food Prot. 2012;75(2):408-418. PubMed
  19. King LA, Nogareda F, Weill FX, Mariani-Kurkdjian P, Loukiadis E, Gault G, Jourdan-DaSilva N, Bingen E, Macé M, Thevenot D, Ong N, Castor C, Noël H, Van Cauteren D, Charron M, Vaillant V, Aldabe B, Goulet V, Delmas G, Couturier E, Le Strat Y, Combe C, Delm
  20. Reeder C, Legrand A, O'Connor-Von SK. The Effect of Fenugreek on Milk Production and Prolactin Levels in Mothers of Preterm Infants. Clinical Lactation 2013;4(4):159-165. DOI
  21. Al-Jenoobi FI, Ahad A, Mahrous GM, Al-Mohizea AM, AlKharfy KM, Al-Suwayeh SA. Effects of fenugreek, garden cress, and black seed on theophylline pharmacokinetics in beagle dogs. Pharm Biol 2015;53(2):296-300. PubMed
  22. Rao A, Steels E, Inder WJ, Abraham S, Vitetta L. Testofen, a specialised Trigonella foenum-graecum seed extract reduces age-related symptoms of androgen decrease, increases testosterone levels and improves sexual function in healthy aging males in a doubl
  23. Steels E, Rao A, Vitetta L. Physiological aspects of male libido enhanced by standardized Trigonella foenum-graecum extract and mineral formulation. Phytother Res. 2011 Sep;25(9):1294-300.
  24. Gong J, Fang K, Dong H, Wang D, Hu M, Lu F. Effect of fenugreek on hyperglycaemia and hyperlipidemia in diabetes and prediabetes: A meta-analysis. J Ethnopharmacol. 2016 Dec 24;194:260-268. PubMed
  25. Ouzir M, El Bairi K, Amzazi S. Toxicological properties of fenugreek (Trigonella foenum graecum). Food Chem Toxicol. 2016 Oct;96:145-54. PubMed
  26. Khodamoradi K, Khosropanah MH, Ayati Z, et al. The Effects of Fenugreek on Cardiometabolic Risk Factors in Adults: A Systematic Review and Meta-analysis. Complement Ther Med. 2020;52:102416. PubMed
  27. Alkharfy K, Jan B, Alotaibi K, et al. Clopidogrel-herb Interactions: A Pharmacokinetic and Pharmacodynamic Assessment in a Rat Model. Curr Drug Metab 2021;22(12):969-977. PubMed
  28. Bin Jardan YA, Ahad A, Raish M, Alam MA, Al-Mohizea AM, Al-Jenoobi FI. Effects of garden cress, fenugreek and black seed on the pharmacodynamics of metoprolol: an herb-drug interaction study in rats with hypertension. Pharm Biol 2021;59(1):1088-1097. PubMed
  29. Al-Mohizea AM, Ahad A, El-Maghraby GM, et al. Effects of Nigella sativa, Lepidium sativum and Trigonella foenum-graecum on sildenafil disposition in beagle dogs. Eur J Drug Metab Pharmacokinet. 2015;40(2):219-24. PubMed
  30. Alkharfy KM, Al-Jenoobi FI, Al-Mohizea AM, et al. Effects of Lepidium sativum, Nigella sativa and Trigonella foenum-graceum on phenytoin pharmacokinetics in beagle dogs. Phytother Res. 2013;27(12):1800-4.

See these in context on the Fenugreek monograph →

Rhodiola 13 references
  1. Kim SH, Hyun SH, Choung SY. Antioxidative effects of Cinnamomi cassiae and Rhodiola rosea extracts in liver of diabetic mice. Biofactors 2006;26:209-19.
  2. Kwon YI, Jang HD, Shetty K. Evaluation of Rhodiola crenulata and Rhodiola rosea for management of type II diabetes and hypertension. Asia Pac J Clin Nutr 2006;15:425-32.
  3. Bystritsky A, Kerwin L, Feusner JD. A pilot study of Rhodiola rosea (Rhodax) for generalized anxiety disorder (GAD). J Altern Complement Med 2008;14:175-80.
  4. Shevtsov VA, Zholus BI, Shervarly VI, et al. A randomized trial of two different doses of a SHR-5 Rhodiola rosea extract versus placebo and control of capacity for mental work. Phytomedicine 2003;10:95-105. PubMed
  5. Apostolidis E, Kwon YI, Shetty K. Potential of cranberry-based herbal synergies for diabetes and hypertension management. Asia Pac J Clin Nutr 2006;15:433-41.
  6. Hellum BH, Tosse A, Hoybakk K, et al. Potent in vitro inhibition of CYP3A4 and P-glycoprotein by Rhodiola rosea. Planta Med 2010;76:331-8.
  7. Skopriska-Rozewska E, Wojcik R, Siwicki AK, et al. The effect of Rhodiola quadrifida extracts on cellular immunity in mice and rats. Pol J Vet Sci 2008;11:105-11.
  8. Mishra KP, Chanda S, Shukla K, Ganju L. Adjuvant effect of aqueous extract of Rhodiola imbricate rhizome on the immune responses to tetanus toxoid and ovalbumin in rats. Immunopharmacol Immunotoxicol 2010;32:141-6.
  9. Li HX, Sze SC, Tong Y, Ng TB. Production of Th1- and Th2-dependent cytokines induced by the Chinese medicine herb, Rhodiola algida, on human peripheral blood monocytes. J Ethnopharmacol 2009;123:257-66. PubMed
  10. Mishra KP, Ganju L, Chanda S, et al. Aqueous extract of Rhodiola imbricate rhizome stimulates Toll-like receptor 4, granzyme-B and Th1 cytokines in vitro. Immunobiology 2009;214:27-31.
  11. Thu OK, Nilsen OG, Hellum B. In vitro inhibition of cytochrome P-450 activities and quantification of constituents in a selection of commercial Rhodiola rosea products. Pharm Bio. 2016 Dec;54(12):3249-3256.
  12. Thu OK, Spigset O, Nilsen OG, Hellum B. Effect of commercial Rhodiola rosea on CYP enzyme activity in humans. Eur J Clin Pharmacol. 2016 Mar;72(3):295-300. PubMed
  13. Woron J, Siwek M. Unwanted effects of psychotropic drug interactions with medicinal products and diet supplements containing plant extracts. Psychiatr Pol 2018;52(6):983-96. PubMed

See these in context on the Rhodiola monograph →

Stinging Nettle 23 references
  1. Monographs on the medicinal uses of plant drugs. Exeter, UK: European Scientific Co-op Phytother, 1997.
  2. Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
  3. The Review of Natural Products by Facts and Comparisons. St. Louis, MO: Wolters Kluwer Co., 1999.
  4. Schulz V, Hansel R, Tyler VE. Rational Phytotherapy: A Physician's Guide to Herbal Medicine. Terry C. Telger, transl. 3rd ed. Berlin, GER: Springer, 1998.
  5. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
  6. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.
  7. Mittman P. Randomized, double-blind study of freeze-dried Urtica dioica in the treatment of allergic rhinitis. Planta Med 1990;56:44-7.
  8. Vontobel HP, Herzog R, Rutishauser G, Kres H. [Results of a double-blind study on the effectiveness of ERU (extractum radicis Urticae) capsules in conservative treatment of benign prostatic hyperplasia]. (Abstract). Urologe A 1985;24:49-51.
  9. Randall C, Randall H, Dobbs F, et al. Randomized controlled trial of nettle sting for treatment of base-of-thumb pain. J R Soc Med 2000;93:305-9. PubMed
  10. Caliskaner Z, Karaayvaz M, Ozturk S. Misuse of a herb: stinging nettle (Urtica urens) induced severe tongue oedema. Complement Ther Med 2004;12:57-8. PubMed
  11. Krzeski, T., Kazon, M., Borkowski, A., Witeska, A., and Kuczera, J. Combined extracts of Urtica dioica and Pygeum africanum in the treatment of benign prostatic hyperplasia: double-blind comparison of two doses. Clin Ther 1993;15(6):1011-1020.
  12. Randall, C., Meethan, K., Randall, H., and Dobbs, F. Nettle sting of Urtica dioica for joint pain--an exploratory study of this complementary therapy. Complement Ther Med 1999;7(3):126-131. PubMed
  13. Tahri, A., Yamani, S., Legssyer, A., Aziz, M., Mekhfi, H., Bnouham, M., and Ziyyat, A. Acute diuretic, natriuretic and hypotensive effects of a continuous perfusion of aqueous extract of Urtica dioica in the rat. J Ethnopharmacol 2000;73(1-2):95-100. PubMed
  14. Sahin, M., Yilmaz, H., Gursoy, A., Demirel, A. N., Tutuncu, N. B., and Guvener, N. D. Gynaecomastia in a man and hyperoestrogenism in a woman due to ingestion of nettle (Urtica dioica). N.Z.Med.J. 2007;120(1265):U2803.
  15. Randall, C., Dickens, A., White, A., Sanders, H., Fox, M., and Campbell, J. Nettle sting for chronic knee pain: a randomised controlled pilot study. Complement Ther.Med. 2008;16(2):66-72. PubMed
  16. Rayburn, K., Fleischbein, E., Song, J., Allen, B., Kundert, M., Leiter, C., and Bush, T. Stinging nettle cream for osteoarthritis. Altern.Ther.Health Med. 2009;15(4):60-61.
  17. Oliver, F., Amon, E. U., Breathnach, A., Francis, D. M., Sarathchandra, P., Black, A. K., and Greaves, M. W. Contact urticaria due to the common stinging nettle (Urtica dioica)-- histological, ultrastructural and pharmacological studies. Clin Exp Dermato PubMed
  18. Kulze, A. and Greaves, M. Contact urticaria caused by stinging nettles. Br.J Dermatol. 1988;119(2):269-270. PubMed
  19. Patten G. Medicinal plant review: Urtica. Aust J Med Herbalism 1993;5(1):5-13.
  20. Maor D, Little M. Skin contact with a stinging tree requiring intensive care unit admission. Contact Dermatitis. 2017 Nov;77(5):335-37. PubMed
  21. Easton L, Vaid S, Nagel AK, Venci JV, Fortuna RJ. Stinging Nettle (Urtica dioica): An Unusual Case of Galactorrhea. Am J Case Rep 2021;22:e933999. PubMed
  22. Niazi B, Ahmed K, Ahmed M, Ali S, Song K, Elias S. Drug-Induced Liver Injury from Herbal Liver Detoxification Tea. Case Rep Gastroenterol 2022;16(3):612-617. PubMed
  23. Nnamani I, Tolu-Akinnawo O, Dufera RR, Akintunde A, Maliakkal B. Tinospora cordifolia (Guduchi/Giloy)-Induced Liver Injury: A Case Review. Cureus 2023;15(5):e39793. PubMed

See these in context on the Stinging Nettle monograph →

Eurycoma Longifolia 4 references
  1. Salman SA, Amrah S, Wahab MS, et al. Modification of propranolol's bioavailability by Eurycoma longifolia water-based extract. J Clin Pharm Ther 2010;35:691-6. PubMed
  2. Tambi MI, Imran MK, Henkel RR. Standardised water-soluble extract of Eurycoma longifolia, Tongkat ali, as testosterone booster for managing men with late-onset hypogonadism? Andrologia 2011 Jun 15. doi: 10.1111/j.1439-0272.2011.01168.x. [Epub ahead of pri PubMed
  3. Han YM, Kim IS, Rehman SU, Choe K, Yoo HH. In vitro evaluation of the effects of Eurycoma longifolia extract on CYP-mediated drug metabolism. Evid Based Complement Alternat Med 2015;2015:631329.
  4. Chinnappan SM, George A, Pandey P, Narke G, Choudhary YK. Effect of Eurycoma longifolia standardised aqueous root extract-Physta ® on testosterone levels and quality of life in ageing male subjects: a randomised, double-blind, placebo-controlled multicent

See these in context on the Eurycoma Longifolia monograph →

Diindolylmethane 14 references
  1. Natl Inst Health, Natl Inst Environmental Health Sci. Indole-3-carbinol. Available at: http://ntp-server.niehs.nih.gov.
  2. Balk JL. Indole-3-carbinol for cancer prevention. Altern Med Alert 2000; 3:105-7.
  3. Riby JE, Chang GHF, Firestone GL, Bjeldanes LF. Ligand-independent activation of estrogen receptor function by 3,3'-diindolylmethane in human breast cancer cells. Biochem Pharmacol 2000;60:167-77. PubMed
  4. Lake BG, Tredger JM, Renwick AB, et al. 3'3-diindolylmethane induces CYP1A2 in cultured precision-cut human liver slices. Xenobiotica 1998;28:803-11. PubMed
  5. Dalessandri, K. M., Firestone, G. L., Fitch, M. D., Bradlow, H. L., and Bjeldanes, L. F. Pilot study: effect of 3,3'-diindolylmethane supplements on urinary hormone metabolites in postmenopausal women with a history of early-stage breast cancer. Nutr Canc PubMed
  6. Reed, G. A., Arneson, D. W., Putnam, W. C., Smith, H. J., Gray, J. C., Sullivan, D. K., Mayo, M. S., Crowell, J. A., and Hurwitz, A. Single-dose and multiple-dose administration of indole-3-carbinol to women: pharmacokinetics based on 3,3'-diindolylmetha
  7. Reed, G. A., Sunega, J. M., Sullivan, D. K., Gray, J. C., Mayo, M. S., Crowell, J. A., and Hurwitz, A. Single-dose pharmacokinetics and tolerability of absorption-enhanced 3,3'-diindolylmethane in healthy subjects. Cancer Epidemiol.Biomarkers Prev. 2008; PubMed
  8. Del Priore G., Gudipudi, D. K., Montemarano, N., Restivo, A. M., Malanowska-Stega, J., and Arslan, A. A. Oral diindolylmethane (DIM): pilot evaluation of a nonsurgical treatment for cervical dysplasia. Gynecol.Oncol. 2010;116(3):464-467. PubMed
  9. Heath, E. I., Heilbrun, L. K., Li, J., Vaishampayan, U., Harper, F., Pemberton, P., and Sarkar, F. H. A phase I dose-escalation study of oral BR-DIM (BioResponse 3,3'- Diindolylmethane) in castrate-resistant, non-metastatic prostate cancer. Am.J.Transl.R
  10. Jellinck, P. H., Forkert, P. G., Riddick, D. S., Okey, A. B., Michnovicz, J. J., and Bradlow, H. L. Ah receptor binding properties of indole carbinols and induction of hepatic estradiol hydroxylation. Biochem.Pharmacol. 3-9-1993;45(5):1129-1136. PubMed
  11. Bui PV, Moualla M, Upson DJ. A Possible Association of Diindolylmethane with Pulmonary Embolism and Deep Venous Thrombosis. Case Rep Med. 2016;2016:7527098. PubMed
  12. Castañon A, Tristram A, Mesher D, Powell N, Beer H, Ashman S, Rieck G, Fielder H, Fiander A, Sasieni P. Effect of diindolylmethane supplementation on low-grade cervical cytological abnormalities: double-blind, randomised, controlled trial. Br J Cancer. 20 PubMed
  13. Le TM, Sanders CJ, van de Corput L, van Erpecum KJ, Röckmann H. Drug rash with eosinophilia and systemic symptoms caused by the dietary supplement diindolylmethane. J Allergy Clin Immunol Pract. 2016 Jan-Feb;4(1):175-6. PubMed
  14. Pence ST, Mehta K, Crum-Bailey J. The Serious Side of Supplements: An Ischemic Stroke in a Healthy 38-year-old Female. Mil Med 2022. PubMed

See these in context on the Diindolylmethane 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.
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Toothed Clubmoss 3 references
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Parts of this content are provided by the Therapeutic Research Center, LLC.

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.

© 2021 Therapeutic Research Center, LLC

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