Major interaction on record — check this product against your medications before combining. Based on 8 of 9 ingredients. Check your meds →
Dietary supplement

R-PCT Ingredients & Drug Interactions

by Repp Sports

R-PCT label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking R-PCT 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: Major

R-PCT is a dietary supplement by Repp Sports with 9 active ingredients. Its ingredients are commonly taken for bone health and osteoporosis, correcting vitamin d deficiency, immune system support.Based on those ingredients, 1,569 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Ashwagandha root extract, Black Pepper extract, Coleus Forskohlii. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against R-PCT by Repp Sports

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HelloPharmacist Scorecard of R-PCT by Repp Sports

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 Sep 10, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 9 of its 9 active ingredients.
  • “Anabolic Test Amplifier” is listed as a grouped ingredient — the label gives one combined amount (555 mg) without saying how much of each component you get.
  • “Estrogen Control” is listed as a grouped ingredient — the label gives one combined amount (275 mg) without saying how much of each component you get.
  • “Liver Regeneration Matrix” is a proprietary blend — the label gives one combined amount (400 mg) without saying how much of each component you get.

R-PCT contains 9 active ingredients. The primary one is vitamin D3, a fat-soluble nutrient essential for bone health and calcium absorption.

N-acetyl cysteine (NAC) is an amino acid that supports antioxidant defenses and respiratory function. Mucuna pruriens is a plant extract containing levodopa, a dopamine precursor.

Black pepper extract provides piperine, a compound that enhances nutrient absorption. Coleus forskohlii delivers forskolin, believed to support cellular energy.

Diindolylmethane (DIM) is a compound from cruciferous vegetables with potential hormonal effects. Ashwagandha is an adaptogenic herb traditionally used for stress and sleep support.

Androsta-3,5-diene-7,17-dione (arimistane) is a hormone-modulating compound. The product also includes three branded blends—Anabolic Test Amplifier, Estrogen Control, and Liver Regeneration Matrix—whose specific component doses are not detailed on this label.

Inactive ingredients include gelatin capsule material, magnesium stearate, and silicon dioxide.

Does it work?

Not established
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
Not established

The graded evidence we hold for these ingredients covers different conditions than the ones this product is marketed for, so there's no established rating for its stated use.

Why this rating?
  • The label markets this product for: Post-cycle therapy testosterone and estrogen support.
  • We looked for evidence on: Athletic performance, Hormone balance, Hormonal recovery, Gynecomastia.
  • The closest evidence on file: Black Pepper is rated "Insufficient Reliable Evidence To Rate" for Athletic performance (Natural Medicines).
  • Also on file: Vitamin D is rated "Insufficient Reliable Evidence To Rate" for Athletic performance.
  • Also on file: Ashwagandha is rated "Insufficient Reliable Evidence To Rate" for Athletic performance.

Vitamin D3 is effective for rickets, osteomalacia (soft bone disease), renal osteodystrophy, and hypoparathyroidism. For the other active ingredients, evidence is less established: ashwagandha is possibly effective for insomnia, anxiety, and stress, but diindolylmethane, N-acetyl cysteine (in most claimed uses), Mucuna pruriens, black pepper, coleus, and arimistane all lack sufficient reliable evidence to rate their effectiveness for the conditions manufacturers often promote them for.

NAC is effective for acetaminophen poisoning and for clearing airways (atelectasis and bronchial studies) and is possibly effective for bronchitis.

The evidence, ingredient by ingredient Vitamin D Cowhage Black Pepper Coleus Ashwagandha Diindolylmethane Arimistane N-acetyl Cysteine (nac)

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 7 of the 8 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 8 of 8.
  • General safety write-ups exist for 8 of 8.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Vitamin D3 is generally well tolerated at recommended doses but can cause toxicity if taken in very high amounts over time, with symptoms of high blood calcium (hypercalcemia), kidney problems, and anemia. It's likely safe in pregnancy at recommended amounts under medical guidance, and likely safe while breastfeeding at recommended doses.

N-acetyl cysteine is generally well tolerated at typical doses; most side effects occur at single doses above 9 grams or daily regimens above 30 grams. Common oral side effects include nausea, diarrhea, dry mouth, and heartburn.

It's possibly safe in pregnancy but has not been well studied; use caution while breastfeeding. Diindolylmethane is generally well tolerated short-term but long-term safety is unclear; common side effects include nausea, diarrhea, headache, gas, and rash.

Avoid it in pregnancy and breastfeeding due to hormone effects and lack of safety data. Mucuna pruriens contains levodopa (a drug-like compound) and should be used carefully; avoid it in pregnancy and while breastfeeding because levodopa can lower prolactin and reduce milk supply.

Ashwagandha is generally well tolerated short-term in healthy adults, with rare cases of liver damage reported; avoid it in pregnancy due to traditional miscarriage concerns and avoid it while breastfeeding due to insufficient safety data. Black pepper is generally safe as a food spice at normal amounts; supplement-strength piperine should be used cautiously.

Coleus may lower blood pressure and is not well studied long-term; avoid it in pregnancy and breastfeeding. Arimistane is a hormone-altering drug with little safety data; regulators warn against aromatase inhibitor supplements, and it's possibly unsafe in pregnancy and breastfeeding.

Side effects, ingredient by ingredient Vitamin D Cowhage Black Pepper Coleus Ashwagandha Diindolylmethane Arimistane N-acetyl Cysteine (nac)

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

At least one ingredient has a documented Major-severity interaction. Check your medications for a personalized result.

Why this rating?
  • 8 of the 8 matched ingredients can interact with medications — Black Pepper, Vitamin D, Ashwagandha, N-acetyl Cysteine (nac), Cowhage, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications; lithium; Parkinson's medications.
  • For scale: 1,570 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 these medication types before taking R-PCT: nitroglycerin (N-acetyl cysteine poses Major risk of severe low blood pressure), MAOIs and methyldopa (Mucuna pruriens poses Major risk of dangerous blood pressure swings), nitrates and calcium channel blockers (coleus poses Major risk of excessive heart effects), and then Moderate-severity concerns with antihypertensive drugs, blood thinners and antiplatelet drugs, digoxin and other heart rhythm drugs, thyroid hormones, antidiabetes drugs, benzodiazepines, CNS depressants, hormone-based medications, and a long list of others metabolized through liver pathways. If you take any regular medication, run it through the search tool on this page.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Major medication interactions have been identified, and safety information is well characterized.

This is a complex multi-ingredient product intended for muscle and hormone support, but it carries a high interaction burden—particularly with blood pressure medications, heart drugs, and brain-active substances. It's not appropriate if you take nitroglycerin, MAOIs, methyldopa, most antihypertensive drugs, anticoagulants, or thyroid medication without a careful conversation first.

Before you start, discuss it with your doctor or pharmacist to check whether any of your medications conflict with these ingredients.

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

Assessment coverage: 8 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 22, 2019.

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 R-PCT, straight from the product label.

Brand Repp Sports
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Dec 22, 2019
DSLD ID 210114
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses No Claim
Intended target group(s) Adult (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 R-PCT by Repp Sports, 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
30
IngredientAmount% DV
Vitamin D32000 UI500%
Diindolymethane200 mg--
5-Alpha Hydroxy Laxogenin25 mg--
N-Acetyl Cysteine400 mg--
Androsta-3, 5-Diene-7, 17-Dione75 mg--
Mucuna pruriens100 mg--
Black Pepper extract5 mg--
Coleus Forskohlii125 mg--
Anabolic Test Amplifier555 mg--
Ashwagandha root extract300 mg--
Estrogen Control275 mg--
Liver Regeneration Matrix400 mg--

Other ingredients: Gelatin, Magnesium Stearate, Silicon 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.
Formulation

Post Cycle Therapy Testosterone Support Suppress Estrogen Liver Regeneration

General Statements

Rapid Injection

Suggested/Recommended/Usage/Directions

Once daily

FDA Statement of Identity

Dietary Supplement

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

See for yourself

R-PCT by Repp Sports label

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

R-PCT 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 R-PCT by Repp Sports

These are the 9 active ingredients this product is made of. Select any to open its full monograph.

Serving size2 Capsule(s) Dosage formCapsule Servings per container30 Amounts shown are per serving.

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

Vitamin D3

Interacts with
715 drugs
2000 UI per serving

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people,...

Vitamin D3 monograph & interactions

Anabolic Test Amplifier

555 mg per serving

Estrogen Control

275 mg per serving

Liver Regeneration Matrix

400 mg per serving

Other (inactive) ingredients: Gelatin, Magnesium Stearate, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

R-PCT by Repp Sports Drug Interactions

Want to check YOUR meds against R-PCT?

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
1,569Drugs
46 Major 1,485 Moderate 38 Minor

Ingredients driving the most interactions

Ashwagandha root extract 1,372
Black Pepper extract 1,019
Coleus Forskohlii 915
Vitamin D3 715
N-Acetyl Cysteine 294

Individual Drug Interactions

The ingredients in R-PCT interact with 1,569 drugs. Click any drug to see the details.

8 of the 9 ingredients in R-PCT interact with drugs. Each result below shows which ingredient is responsible. Ashwagandha root extract Black Pepper extract Coleus Forskohlii Vitamin D3 N-Acetyl Cysteine Diindolymethane Mucuna pruriens Androsta-3, 5-Diene-7, 17-Dione

Each ingredient & the kinds of drugs it affects

For each ingredient in R-PCT 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 extract10 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

Black Pepper 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 extract full monograph & interactions

Coleus Forskohlii7 drug types · 915 drugs

Calcium Channel Blockers

Theoretically, combining coleus with calcium channel blockers might increase the coronary vasodilatory effects.
Forskolin, a constituent of coleus, and calcium channel blockers both cause coronary vasodilatory effects.

Likelihood Probable Evidence B
Nitrates

Theoretically, combining coleus with nitrates might increase the coronary vasodilatory effects.
Forskolin, a constituent of coleus, and nitrates both cause coronary vasodilatory effects.

Likelihood Probable Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, concomitant use of coleus and anticoagulant or antiplatelet drugs might increase the risk of bruising and bleeding.
In vitro and animal research shows that forskolin, a constituent of coleus, can inhibit platelet aggregation and adhesion.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, combining coleus with antihypertensive drugs might cause additive blood pressure lowering effects and increase the risk of hypotension.
Animal research shows that forskolin, a constituent of coleus, may lower blood pressure.

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

Theoretically, taking coleus may affect drugs metabolized by CYP2C9 and increase the risk of adverse effects or reduce the effectiveness.
Research on the effect of coleus on CYP2C9 is conflicting. Some animal research shows that coleus extract can induce CYP2C9, while in vitro research shows that coleus can inhibit CYP2C9. Until more is known, advise patients that taking coleus might increase or decrease levels of drugs metabolized by CYP2C9.

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

Theoretically, taking coleus might decrease serum levels of drugs metabolized by CYP3A4.
In vitro research shows that coleus can activate the nuclear receptor, pregnane X receptor (PXR), which results in increased expression of CYP3A4. Although the clinical significance of this is not known, use caution when considering concomitant use of coleus and other drugs affected by these enzymes.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, taking coleus may affect the metabolism of warfarin and increase the risk of adverse effects or reduce the effectiveness.
Some animal research shows that coleus extract can induce cytochrome P450 2C9 (CYP2C9), an enzyme that metabolizes warfarin. However, other in vitro research shows that coleus can inhibit CYP2C9. Theoretically, taking coleus with drugs metabolized by CYP2C9 might affect drug levels and the risk of adverse effects. Until more is known, advise patients that taking coleus might increase or decrease levels of warfarin.

Likelihood Possible Evidence D
Coleus Forskohlii full monograph & interactions

Vitamin D38 drug types · 715 drugs

Aluminum

Vitamin D might increase aluminum absorption and toxicity, but this has only been reported in people with renal failure.
The protein that transports calcium across the intestinal wall can also bind and transport aluminum. This protein is stimulated by vitamin D, which may therefore increase aluminum absorption. This mechanism may contribute to increased aluminum levels and toxicity in people with renal failure, when they take vitamin D and aluminum-containing phosphate binders chronically.

Likelihood Probable Evidence B
Atorvastatin (Lipitor)

Vitamin D might reduce absorption of atorvastatin.
A small, low-quality clinical study shows that taking vitamin D reduces levels of atorvastatin and its active metabolites by up to 55%. However, while atorvastatin levels decreased, total cholesterol, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein (HDL) cholesterol levels did not substantially change. Atorvastatin is metabolized in the gut by CYP3A4 enzymes, and researchers theorized that vitamin D might induce CYP3A4, causing reduced levels of atorvastatin. However, this proposed mechanism was not specifically studied.

Likelihood Probable Evidence B
Calcipotriene (Dovonex)

Taking calcipotriene with vitamin D increases the risk for hypercalcemia.
Calcipotriene is a vitamin D analog used topically for psoriasis. It can be absorbed in sufficient amounts to cause systemic effects, including hypercalcemia. Theoretically, combining calcipotriene with vitamin D supplements might increase the risk of hypercalcemia.

Likelihood Probable Evidence D
Digoxin (Lanoxin)

Theoretically, hypercalcemia induced by high-dose vitamin D can increase the risk of arrhythmia from digoxin.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia increases the risk of fatal cardiac arrhythmias with digoxin. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and digoxin concurrently.

Likelihood Possible Evidence D
Diltiazem (Cardizem, Others)

Theoretically, hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of diltiazem for arrhythmia.
High doses of vitamin D can cause hypercalcemia. Hypercalcemia can reduce the effectiveness of verapamil in atrial fibrillation. Theoretically this could also occur with diltiazem. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and diltiazem concurrently.

Likelihood Probable Evidence B
Thiazide Diuretics

Theoretically, taking thiazide diuretics and high-dose vitamin D can increase the risk of hypercalcemia.
Thiazide diuretics decrease urinary calcium excretion, which could lead to hypercalcemia if vitamin D supplements are taken concurrently. This has been reported in people being treated with vitamin D for hypoparathyroidism, and also in elderly people with normal parathyroid function who were taking a thiazide, vitamin D, and calcium-containing antacids daily.

Likelihood Probable Evidence D
Verapamil (Calan, Others)

Hypercalcemia induced by high-dose vitamin D can reduce the therapeutic effects of verapamil for arrhythmia.
Hypercalcemia due to high doses of vitamin D can reduce the effectiveness of verapamil in atrial fibrillation. Avoid vitamin D doses above the tolerable upper intake level (4000 IU daily for adults) and monitor serum calcium levels in people taking vitamin D and verapamil concurrently.

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

Vitamin D might induce CYP3A4 enzymes and reduce the bioavailability of CYP3A4 substrates.
There is some concern that vitamin D might induce CYP3A4. In vitro research suggests that vitamin D induces CYP3A4 transcription. Additionally, observational research has found that increased UV light exposure and serum vitamin D levels are associated with decreased serum levels of CYP3A4 substrates such as tacrolimus and sirolimus, while no association between UV light exposure or vitamin D levels and levels of mycophenolic acid, a non-CYP3A4 substrate, was found. A small, low-quality clinical study shows that taking vitamin D reduces levels of the CYP3A4 substrate atorvastatin and its active metabolites by up to 55%; however, the clinical effects of atorvastatin were not reduced. While researchers theorized that vitamin D might induce CYP3A4, this proposed mechanism was not specifically studied.

Likelihood Possible Evidence D
Vitamin D3 full monograph & interactions

N-Acetyl Cysteine5 drug types · 294 drugs

Nitroglycerin

N-acetyl cysteine can increase the risk for hypotension and headaches when taken with intravenous or transdermal nitroglycerin.
Clinical research shows that concomitant administration of N-acetyl cysteine and intravenous or transdermal nitroglycerin can cause severe hypotension and intolerable headaches. Furthermore, in vitro research suggests that N-acetyl cysteine increases the anticoagulant activity of nitroglycerin.

Likelihood Probable Evidence B
Activated Charcoal

N-acetyl cysteine might reduce the effects of activated charcoal, while activated charcoal might reduce the absorption of N-acetyl cysteine.
N-acetyl cysteine appears to reduce the capacity of activated charcoal to adsorb acetaminophen and salicylic acid. Conversely, although clinical research suggests that although activated charcoal can reduce the absorption of N-acetyl cysteine by up to 40%, it does not seem to reduce its clinical effects. Other clinical evidence suggests that activated charcoal does not affect the absorption of N-acetyl cysteine.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, N-acetyl cysteine might increase the risk of bleeding when taken with anticoagulant or antiplatelet drugs.
Clinical research suggests that intravenous N-acetyl cysteine decreases prothrombin time, prolongs coagulation time, decreases platelet aggregation, and increases blood loss in surgical patients. Furthermore, in vitro research suggests that N-acetyl cysteine increases the anticoagulant activity of nitroglycerin.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, N-acetyl cysteine might increase the risk of hypotension when taken with antihypertensive drugs.
Animal research suggests that N-acetyl cysteine potentiates the hypotensive effects of the angiotensin-converting enzyme inhibitors (ACEIs) captopril and enalaprilat. Theoretically, combining N-acetyl cysteine with other antihypertensive drugs might increase the risk of hypotension.

Likelihood Possible Evidence D
Chloroquine (Aralen)

Theoretically, N-acetyl cysteine might interfere with the antimalarial effects of chloroquine.
Animal research suggests that N-acetyl cysteine might reduce the antimalarial effects of chloroquine by increasing cellular levels of glutathione.

Likelihood Possible Evidence D
N-Acetyl Cysteine full monograph & interactions

Diindolymethane3 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
Diindolymethane full monograph & interactions

Mucuna pruriens8 drug types · 193 drugs

Levodopa

Concomitant use can increase the risk of levodopa-related adverse effects.
Cowhage contains levodopa. Some cowhage products have been standardized to contain 75-400 mg of levodopa per dose.

Likelihood Likely Evidence D
Methyldopa (Aldomet)

Theoretically, concomitant use of cowhage and methyldopa might increase the risk of hypotension.
Cowhage contains levodopa. Use of levodopa with methyldopa might cause additive hypotension. In addition, methyldopa may inhibit peripheral decarboxylation of levodopa and increase levodopa levels in the central nervous system; avoid using.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use of cowhage and non-selective MAOIs might increase the risk of hypertensive crisis.
Cowhage contains levodopa. Use of levodopa with non-selective MAOIs might cause hypertensive crisis. However, this interaction has not been reported with MAO-B selective inhibitors such as selegiline.

Likelihood Probable Evidence D
Anesthesia

Theoretically, concomitant use of cowhage and anesthesia might increase the risk of arrhythmias.
Cowhage contains levodopa. Use of levodopa with cyclopropane or halogenated hydrocarbon anesthesia has led to arrhythmias. Other anesthetics have not been implicated. Use other anesthetics in patients taking cowhage or tell patients to stop taking cowhage at least 2 weeks before surgery.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, concomitant use of cowhage and antidiabetes drugs might increase the risk of hypoglycemia.
Animal research shows that cowhage might have hypoglycemic effects.

Likelihood Possible Evidence D
Antipsychotic Drugs

Theoretically, use of cowhage might decrease the clinical effects of antipsychotic drugs.
Cowhage contains levodopa. Use of levodopa might counteract the antidopaminergic effects of antipsychotic medications.

Likelihood Possible Evidence D
Guanethidine (Ismelin)

Theoretically, concomitant use of cowhage and guanethidine might increase the risk of hypotension.
Cowhage contains levodopa. Use of levodopa with guanethidine might cause additive hypotension; avoid using.

Likelihood Probable Evidence D
Tricyclic Antidepressants (Tcas)

Theoretically, use of TCAs might reduce the levels and clinical effects of cowhage.
Cowhage contains levodopa. Use of TCAs might reduce the absorption of levodopa. Some case reports describe patients that developed hypertension and dyskinesia when taking both levodopa and TCAs.

Likelihood Possible Evidence D
Mucuna pruriens full monograph & interactions

Androsta-3, 5-Diene-7, 17-Dione1 drug type · 4 drugs

Aromatase Inhibitors

It is believed that Arimistane inhibits the aromatase enzyme, which may interact with other aromatase inhibitors. This interaction could potentially increase the risk of side effects associated with low estrogen levels or from additive side effects, such as an increased risk of liver toxicity. It is recommended to consult with a healthcare provider before combining Arimistane with other aromatase inhibitors to assess the potential risks and benefits.

Likelihood Probable Evidence C
Androsta-3, 5-Diene-7, 17-Dione full monograph & interactions
The maker

Brand information

Manufacturer and brand details for R-PCT, from the product label.

Repp Sports

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Name
Repp Sports
Pharmacist Counseling Corner

R-PCT by Repp Sports: Common Questions

Does R-PCT by Repp Sports interact with any medications?
Yes. Based on its ingredients, R-PCT has a known interaction with 1,569 medications, including 46 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
R-PCT contains 9 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is vitamin D3 in this product safe to take if I'm on a water pill (diuretic)?
Thiazide diuretics (common water pills) combined with high-dose vitamin D can theoretically raise your blood calcium too high. The facts show this is a Moderate-severity concern, especially at higher vitamin D doses. Talk with your doctor or pharmacist about your specific blood pressure medication and the dose of vitamin D3 in this product before starting.
What does Mucuna pruriens do, and why is it in a testosterone-support product?
Mucuna pruriens contains levodopa, a dopamine precursor, and is traditionally used for sexual function and stress support. It's included here likely for those purposes, though the evidence for its effectiveness isn't well established in our data. However, it carries serious Major-level interactions with certain blood pressure and psychiatric medications, so it's not one to take lightly.
Can I take this if I'm on a blood thinner like warfarin?
Possibly not without oversight. Coleus in this product may affect warfarin metabolism—the facts show conflicting data, with some evidence that it could induce the enzyme that breaks warfarin down and others showing it might inhibit it. You need your doctor or pharmacist to review this before you start, since changes to warfarin levels can have serious bleeding consequences.
What are the common side effects of ashwagandha in this product?
At typical doses, ashwagandha is generally well tolerated. When side effects do occur, they're usually mild gastrointestinal ones—nausea, diarrhea, or stomach upset. Drowsiness has also been reported. Serious liver damage is rare but documented in case reports, so if you have liver disease, flagging this with your doctor is wise.
Is this product safe to take while pregnant or breastfeeding?
No. Several ingredients carry safety concerns: ashwagandha and Mucuna pruriens are best avoided in pregnancy, arimistane is possibly unsafe in pregnancy, and diindolylmethane should be avoided due to hormone effects. Mucuna pruriens can reduce milk supply while breastfeeding. Talk with your doctor before using this product if you're pregnant, planning pregnancy, or nursing.
What is arimistane and why is it in a muscle-support product?
Arimistane (Androsta-3,5-diene-7,17-dione) is a hormone-modulating compound believed to inhibit aromatase, an enzyme that converts testosterone to estrogen. It's included to theoretically raise free testosterone. However, regulators warn against aromatase inhibitor supplements, it has little safety data, and the evidence for its effectiveness is insufficient. It also carries a Moderate interaction risk with prescription aromatase inhibitors used for certain cancers.

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

Not sure if R-PCT is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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

R-PCT label
Go deeper

The Full Monographs Behind R-PCT’s Ingredients

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

Herb & supplement monograph

Vitamin D

Interacts with 715 drugs

Vitamin D is a fat-soluble vitamin that helps your body absorb calcium and is important for healthy bones, muscles, and immune function. Many people, especially those with low sun exposure,...

Read the full Vitamin D monograph → Herb & supplement monograph

Cowhage

Interacts with 193 drugs

Cowhage (Mucuna pruriens) is a tropical legume best known as a natural source of L-dopa, the compound the body turns into dopamine. It is most studied for Parkinson's disease symptoms and ma...

Read the full Cowhage 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 → Herb & supplement monograph

Coleus

Interacts with 915 drugs

Coleus is a plant from the mint family whose root contains a compound called forskolin, often marketed for weight loss, asthma, and heart health. While early lab and small human studies are...

Read the full Coleus 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

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

Arimistane

Interacts with 4 drugs

Arimistane (sometimes sold as Estrovade) is a synthetic aromatase inhibitor marketed as a dietary supplement to lower estrogen and raise testosterone, often during or after steroid or prohor...

Read the full Arimistane monograph → Herb & supplement monograph

N-acetyl Cysteine (nac)

Interacts with 294 drugs

N-acetyl cysteine (NAC) is a supplement form of the amino acid cysteine and a building block for the antioxidant glutathione. It has well-established prescription uses for acetaminophen over...

Read the full N-acetyl Cysteine (nac) monograph →
Sources

Sources & How We Checked

R-PCT'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 216 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.

Vitamin D 26 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Tatro DS, ed. Drug Interactions Facts. Facts and Comparisons Inc., St. Louis, MO. 1999.
  3. Koutkia P, Chen TC, Holick MF. Vitamin D intoxication associated with an over-the-counter supplement. N Engl J Med 2001;345:66-7. PubMed
  4. Bar-Or D, Yoel G. Calcium and calciferol antagonize effect of verapamil in atrial fibrillation. Br Med J 1981;282:1585-6.
  5. Demontis R, Leflon A, Fournier A, et al. 1 alpha(OH) vitamin D3 increases plasma aluminum in hemodialyzed patients taking AI(OH)3. Clin Nephrol 1986;26:146-9.
  6. Crowe M, Wollner L, Griffiths RA. Hypercalcemia following vitamin D and thiazide therapy in the elderly. Practitioner 1984;228:312-3.
  7. Parfitt AM. Thiazide-induced hypercalcemia in vitamin D-treated hypoparathyroidism. Ann Intern Med 1972;77:557-63. PubMed
  8. Thiazide diuretics and the risk of osteoporosis. Pharmacist's Letter/Prescriber's Letter 2003;19(11):191105.
  9. Moon J. The role of vitamin D in toxic metal absorption. J Am Coll Nutr 1994;13:559-64.
  10. Demontis R, Reissi D, Noel C, et al. Indirect clinical evidence that 1alphaOH vitamin D<SUB>3</SUB> increases the intestinal absorption of aluminum. Clin Nephrol 1989;31:123-7.
  11. Adler AJ, Berlyne GM. Duodenal aluminum absorption in the rat: effect of vitamin D. Am J Physiol 1985;249:G209-13. PubMed
  12. Schwartz JB. Effects of vitamin D supplementation in atorvastatin-treated patients: A new drug interaction with an unexpected consequence. Clin Pharmacol Ther 2009;85:198-203. PubMed
  13. Dietary reference intakes for calcium and vitamin D. Institute of Medicine, November 30, 2010. Available at: http://www.iom.edu/~/media/Files/Report%20Files/2010/Dietary-Reference-Intakes-for-Calcium-and-Vitamin-D/Vitamin%20D%20and%20Calcium%202010%20Repo
  14. Cox KA, Dunn MA. Aluminum toxicity alters the regulation of calbindin-D28k protein and mRNA expression in chick intestine. J Nutr 2001;131:2007-13. PubMed
  15. Escribano, J., Balaguer, A., Pagone, F., Feliu, A., and Roque, I. Figuls. Pharmacological interventions for preventing complications in idiopathic hypercalciuria. Cochrane.Database.Syst.Rev. 2009;(1):CD004754. PubMed
  16. Carlton, S., Clopton, D., and Cappuzzo, K. A. Vitamin D deficiency: appropriate replenishment therapies and the effects of vitamin D toxicity. Consult Pharm 2010;25(3):171-177. PubMed
  17. Wang, H., Xia, N., Yang, Y., and Peng, D. Q. Influence of vitamin D supplementation on plasma lipid profiles: a meta-analysis of randomized controlled trials. Lipids Health Dis. 2012;11:42. PubMed
  18. Turner AN, Carr Reese P, Fields KS, Anderson J, Ervin M, Davis JA, Fichorova RN, Roberts MW, Klebanoff MA, Jackson RD. A blinded, randomized controlled trial of high-dose vitamin D supplementation to reduce recurrence of bacterial vaginosis. Am J Obstet G PubMed
  19. Weiner M, Epstein FH. Signs and symptoms of electrolyte disorders. Yale J Biol Med. 1970;43(2):76-109.
  20. Lappe J, Watson P, Travers-Gustafson D, Recker R, Garland C, Gorham E, Baggerly K, McDonnell SL. Effect of Vitamin D and Calcium Supplementation on Cancer Incidence in Older Women: A Randomized Clinical Trial. JAMA. 2017 Mar 28;317(12):1234-1243. PubMed
  21. Roth DE, Leung M, Mesfin E, Qamar H, Watterworth J, Papp E. Vitamin D supplementation during pregnancy: state of the evidence from a systematic review of randomised trials. BMJ. 2017;359:j5237. PubMed
  22. Murai IH, Fernandes AL, Sales LP, et al. Effect of a single high dose of vitamin D3 on hospital length of stay in patients with moderate to severe COVID-19: A randomized clinical trial. JAMA. 2021.
  23. Wang Z, Schuetz EG, Xu Y, Thummel KE. Interplay between vitamin D and the drug metabolizing enzyme CYP3A4. J Steroid Biochem Mol Biol 2013;136:54-8. PubMed
  24. Doyle D, Browne U, Brickley A, Murphy D. Vitamin D-induced hypercalcaemia and acute kidney injury in sarcoidosis. BMJ Case Rep 2023;16(1):e250580. PubMed
  25. Williamson A, Martineau AR, Sheikh A, Jolliffe D, Griffiths CJ. Vitamin D for the management of asthma. Cochrane Database Syst Rev 2023;2(2):CD011511. PubMed
  26. Kinesya E, Santoso D, Gde Arya N, et al. Vitamin D as adjuvant therapy for diabetic foot ulcers: Systematic review and meta-analysis approach. Clin Nutr ESPEN 2023;54:137-143. PubMed

See these in context on the Vitamin D 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 →

N-acetyl Cysteine (nac) 86 references
  1. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.
  2. Jepsen S, Hansen AB. The influence of N-acetylcysteine on the measurement of prothrombin time and activated partial thromboplastin time in healthy subjects. Scand J Clin Lab Invest 1994;54:543-7. PubMed
  3. van Zandwijk N, Dalesio O, Pastorino U, et al. EUROSCAN, a randomized trial of vitamin A and N-acetylcysteine in patients with head and neck cancer or lung cancer. For the European Organization for Research and Treatment of Cancer Head and Neck and Lung C DOI
  4. Horowitz RS, Dart RC, Jarvie DR, et al. Placental transfer of N-acetylcysteine following human maternal acetaminophen toxicity. J Toxicol Clin Toxicol 1997;35:447-51.
  5. Bailey B, McGuigan MA. Management of anaphylactoid reactions to intravenous N-acetylcysteine. Ann Emerg Med 1998;31:710-5. PubMed
  6. Spiller HA, Krenzelok EP, Grande GA, et al. A prospective evaluation of the effect of activated charcoal before oral N-acetylcysteine in acetaminophen overdose. Ann Emerg Med 1994;23:519-23. PubMed
  7. Ardissino D, Merlini PA, Savonitto S, et al. Effect of transdermal nitroglycerin or N-acetylcysteine, or both, in the long-term treatment of unstable angina pectoris. J Am Coll Cardiol 1997;29:941-7. PubMed
  8. Horowitz JD, Henry CA, Syrjanen ML, et al. Nitroglycerine/N-acetylcysteine in the management of unstable angina pectoris. Eur Heart J 1988;9:95-100. PubMed
  9. Louwerse ES, Weverling GJ, Bossuyt PM, et al. Randomized, double-blind, controlled trial of acetylcysteine in amyotrophic lateral sclerosis. Arch Neurol 1995;52:559-64. PubMed
  10. Wiklund O, Fager G, Andersson A, et al. N-acetylcysteine treatment lowers plasma homocysteine but not serum lipoprotein(a) levels. Atherosclerosis 1996;119:99-106. PubMed
  11. De Flora S, Grassi C, Carati L. Attenuation of influenza-like symptomatology and improvement of cell-mediated immunity with long-term N-acetylcysteine treatment. Eur Respir J 1997;10:1535-41. PubMed
  12. Iversen HK. N-acetylcysteine enhances nitroglycerin-induced headache and cranial arterial responses. Clin Pharmacol Ther 1992;52:125-33. PubMed
  13. Behr J, Maier K, Degenkolb B, et al. Antioxidative and clinical effects of high-dose N-acetylcysteine in fibrosing alveolitis. Adjunctive therapy to maintenance immunosuppression. Am J Respir Crit Care Med 1997;156:1897-901.
  14. Tenenbein PK, Sitar DS, Tenenbein M. Interaction between N-acetylcysteine and activated charcoal: implications for the treatment of acetaminophen poisoning. Pharmacotherapy 2001;21:1331-6.
  15. Arstall MA, Yang J, Stafford I, et al. N-acetylcysteine in combination with nitroglycerin and streptokinase for the treatment of evolving acute myocardial infarction. Safety and biochemical effects. Circulation 1995;92:2855-62.
  16. Estensen RD, Levy M, Klopp SJ, et al. N-acetylcysteine suppression of the proliferative index in the colon of patients with previous adenomatous colonic polyps. Cancer Lett 1999;147:109-14. PubMed
  17. Pela R, Calcagni AM, Subiaco S, et al. N-acetylcysteine reduces the exacerbation rate in patients with moderate to severe COPD. Respiration 1999;66:495-500.. PubMed
  18. Oldemeyer JB, Biddle WP, Wurdeman RL, et al. Acetylcysteine in the prevention of contrast-induced nephropathy after coronary angiography. Am Heart J 2003;146:E23. . PubMed
  19. Ekins BR, Ford DC, Thompson MI, et al. The effect of activated charcoal on N-acetylcysteine absorption in normal subjects. Am J Emerg Med. 1987;5(6):483-7. PubMed
  20. Chamberlain JM, Gorman RL, Oderda GM, Klein-Schwartz W, Klein BL. Use of activated charcoal in a simulated poisoning with acetaminophen: a new loading dose for N-acetylcysteine? Ann Emerg Med. 1993;22(9):1398-402. PubMed
  21. Renzi FP, Donovan JW, Martin TG, Morgan L, Harrison EF. Concomitant use of activated charcoal and N-acetylcysteine. Ann Emerg Med. 1985;14(6):568-72. DOI
  22. North DS, Peterson RG, Krenzelok EP. Effect of activated charcoal administration on acetylcysteine serum levels in humans. Am J Hosp Pharm. 1981;38(7):1022-4. DOI
  23. Loscalzo J. N-Acetylcysteine potentiates inhibition of platelet aggregation by nitroglycerin. J Clin Invest. 1985;76(2):703-8. PubMed
  24. Ruiz FJ, Salom MG, Inglés AC, et al. N-acetyl-L-cysteine potentiates depressor response to captopril and enalaprilat in SHRs. Am J Physiol. 1994;267(3 Pt 2):R767-72. PubMed
  25. Deharo E, Barkan D, Krugliak M, Golenser J, Ginsburg H. Potentiation of the antimalarial action of chloroquine in rodent malaria by drugs known to reduce cellular glutathione levels. Biochem Pharmacol. 2003;66(5):809-17. PubMed
  26. Buckley, N. A., Whyte, I. M., O'Connell, D. L., and Dawson, A. H. Oral or intravenous N-acetylcysteine: which is the treatment of choice for acetaminophen (paracetamol) poisoning? J Toxicol.Clin Toxicol. 1999;37(6):759-767.
  27. Sunman, W., Hughes, A. D., and Sever, P. S. Anaphylactoid response to intravenous acetylcysteine. Lancet 5-16-1992;339(8803):1231-1232. PubMed
  28. Reynard, K., Riley, A., and Walker, B. E. Respiratory arrest after N-acetylcysteine for paracetamol overdose. Lancet 9-12-1992;340(8820):675. PubMed
  29. BERNSTEIN, I. L. and AUSDENMOORE, R. W. IATROGENIC BRONCHOSPASM OCCURRING DURING CLINICAL TRIALS OF A NEW MUCOLYTIC AGENT, ACETYLCYSTEINE. Dis.Chest 1964;46:469-473. PubMed
  30. REAS, H. W. THE USE OF N-ACETYLCYSTEINE IN THE TREATMENT OF CYSTIC FIBROSIS. J Pediatr 1964;65:542-557. PubMed
  31. Bibi, H., Seifert, B., Oullette, M., and Belik, J. Intratracheal N-acetylcysteine use in infants with chronic lung disease. Acta Paediatr. 1992;81(4):335-339. PubMed
  32. Jepsen, S., Herlevsen, P., Knudsen, P., Bud, M. I., and Klausen, N. O. Antioxidant treatment with N-acetylcysteine during adult respiratory distress syndrome: a prospective, randomized, placebo-controlled study. Crit Care Med 1992;20(7):918-923. PubMed
  33. Roes, E. M., Raijmakers, M. T., Boo, T. M., Zusterzeel, P. L., Merkus, H. M., Peters, W. H., and Steegers, E. A. Oral N-acetylcysteine administration does not stabilise the process of established severe preeclampsia. Eur.J Obstet.Gynecol.Reprod.Biol 2006
  34. Spiller, H. A., Winter, M. L., Klein-Schwartz, W., and Bangh, S. A. Efficacy of activated charcoal administered more than four hours after acetaminophen overdose. J Emerg.Med 2006;30(1):1-5. PubMed
  35. Tirouvanziam, R., Conrad, C. K., Bottiglieri, T., Herzenberg, L. A., Moss, R. B., and Herzenberg, L. A. High-dose oral N-acetylcysteine, a glutathione prodrug, modulates inflammation in cystic fibrosis. Proc Natl.Acad.Sci U.S.A 3-21-2006;103(12):4628-463
  36. Niemi, T. T., Munsterhjelm, E., Poyhia, R., Hynninen, M. S., and Salmenpera, M. T. The effect of N-acetylcysteine on blood coagulation and platelet function in patients undergoing open repair of abdominal aortic aneurysm. Blood Coagul.Fibrinolysis 2006;1 PubMed
  37. Komisarof, J. A., Gilkey, G. M., Peters, D. M., Koudelka, C. W., Meyer, M. M., and Smith, S. M. N-acetylcysteine for patients with prolonged hypotension as prophylaxis for acute renal failure (NEPHRON). Crit Care Med 2007;35(2):435-441. PubMed
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  28. Majeed M, Nagabhushanam K, Murali A, Vishwanathan DT, Mamidala RV, Mundkur L. A Standardized Withania somniferra (Linn.) Root Extract with Piperine Alleviates the Symptoms of Anxiety and Depression by Increasing Serotonin Levels: A Double-Blind, Randomize
  29. Philips CA, Valsan A, Theruvath AH, et al. Ashwagandha-induced liver injury-A case series from India and literature review. Hepatol Commun 2023;7(10):e0270. PubMed
  30. Hayashi M, Hamada H, Azuma SI, Hayashi K. Painless Thyroiditis by Withania somnifera (Ashwagandha). Cureus 2024;16(3):e55352. PubMed
  31. Vazirani S, Kothari A, Fujimoto J, Gomez M. Supplements Are Not a Synonym for Safe: Suspected Liver Injury From Ashwagandha. Fed Pract 2023;40(9):315-319. PubMed
  32. Patel M, Newell R, Hillier M, Ramalingam R. Herbal remedies as a potential cause of hypoadrenalism. Br J Hosp Med (Lond) 2024;85(6):1-4. PubMed

See these in context on the Ashwagandha monograph →

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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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