Major interaction on record — check this product against your medications before combining. Based on 9 of 10 ingredients. Check your meds →
Dietary supplement

Red Focus Ingredients & Drug Interactions

by Red Supplements

Red Focus label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 23, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Red Focus 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

Red Focus is a dietary supplement by Red Supplements with 10 active ingredients. Its ingredients are commonly taken for anxiety and stress, relaxation and calm, sleep support.Based on those ingredients, 1,498 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Yerba Mate Extract, Black Pepper extract, Bacopa monnieri 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 Red Focus by Red Supplements

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

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HelloPharmacist Scorecard of Red Focus by Red Supplements

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
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 10 of its 10 active ingredients.
  • “Red Focus” is listed as a grouped ingredient — the label gives one combined amount (1,155 mg) without saying how much of each component you get.
Known Interaction Concern
Major identified

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

Why this rating?
  • 9 of the 9 matched ingredients can interact with medications — Bacopa, Huperzine A, Black Pepper, Cocoa, Yerba Mate, 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; lithium.
  • For scale: 1,499 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 8 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 summaryFully disclosed formula with no assessable stated purpose. Major 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 Jul 23, 2020.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about Red Focus, straight from the product label.

Brand Red Supplements
Barcode (UPC) 689407693970
Net contents 60 Capsule(s)
Market status Off market
Date entered into DSLD Jul 23, 2020
DSLD ID 229177
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
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 Red Focus by Red Supplements, 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
UPC/BARCODE
689407693970
IngredientAmount% DV
L-Theanine50 mg--
Yerba Mate Extract150 mg--
Theobromine100 mg--
Phenylethylamine250 mg--
Huperzine A300 mcg--
Hordenine HCl25 mg--
Phosphatidylserine75 mg--
AlphaSize300 mg--
Black Pepper extract5 mg--
Bacopa monnieri extract200 mg--
Red Focus1155 mg--

Other ingredients: Vegetarian Gelatin Capsules, Magnesium Stearate

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.
Storage

Suggested Use Take 2 capsules, once per day, with or without food, 30-60 minutes before beginning a cognitive task.

Store in a cool, dry, place, out of direct sunlight.

Precautions

Warning: Keep out of reach of children. This product is not intended for anyone under the age of 18-years-old.

Consult with a healthcare professional before using this product.

Do not use this product if you have any known or suspected medical conditions and/or if you are currently taking any prescription or OTC medications.

Discontinue use and consult with a healthcare professional if you experience any adverse reactions to this product. Do not exceed the recommended servings.

Do not use if the safety seal is broken or missing.

FDA Disclaimer Statement

These statements have not been evaluated by the FDA. This product is not intended to treat, diagnose, cure, or prevent any disease.

General Statements

Supplements that actually work

FDA Statement of Identity

Dietary Supplement

Seals/Symbols

GMP Good Manufacturing Practice Quality Product Made in USA

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

See for yourself

Red Focus by Red Supplements label

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

Red Focus 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 Red Focus by Red Supplements

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 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.

Red Focus

1155 mg per serving

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

Interaction report

Red Focus by Red Supplements Drug Interactions

Red Focus contains 10 ingredients, and 9 of them have known drug interactions. Altogether they interact with 1,498 medications. Here’s the picture, then you can look up your own drug.

Want to check YOUR meds against Red Focus?

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
1,498Drugs
8 Major 1,399 Moderate 91 Minor

Ingredients driving the most interactions

Yerba Mate Extract 1,086
Black Pepper extract 1,019
Bacopa monnieri extract 930
Theobromine 661
L-Theanine 565

Individual Drug Interactions

The ingredients in Red Focus interact with 1,498 drugs. Click any drug to see the details.

9 of the 10 ingredients in Red Focus interact with drugs. Each result below shows which ingredient is responsible. Yerba Mate Extract Black Pepper extract Bacopa monnieri extract Theobromine L-Theanine Hordenine HCl Huperzine A Phosphatidylserine AlphaSize

Each ingredient & the kinds of drugs it affects

For each ingredient in Red Focus 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.

Yerba Mate Extract43 drug types · 1,086 drugs

Ephedrine

Theoretically, the caffeine in yerba mate might increase the risk for stimulant adverse effects when used concomitantly with ephedrine.
Use of ephedrine with caffeine can increase the risk of stimulatory adverse effects. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death.

Likelihood Probable Evidence D
Adenosine (Adenocard)

Theoretically, the caffeine in yerba mate might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Yerba mate contains caffeine. Some evidence shows that caffeine is a competitive inhibitor of adenosine and can reduce the vasodilatory effects of adenosine in humans. However, other research shows that caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. Still, some researchers recommend that methylxanthines, such as caffeine, as well as methylxanthine-containing products, should be stopped 24 hours prior to pharmacological stress tests. However, methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Possible Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, the caffeine in yerba mate may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Yerba mate contains caffeine. Caffeine is reported to have antiplatelet activity. Theoretically, it might increase the risk of bleeding when used concomitantly with these agents; however, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Benzodiazepines

Theoretically, the caffeine in yerba mate might reduce the efficacy of benzodiazepines.
Yerba mate contains caffeine. Caffeine can antagonize the anxiolytic effects of benzodiazepines.

Likelihood Probable Evidence D
Beta-Adrenergic Agonists

Theoretically, the caffeine in yerba mate might increase the cardiac inotropic effects of beta-agonists, especially if taken in large amounts.
Yerba mate contains caffeine. Caffeine can increase cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Carbamazepine (Tegretol)

Theoretically, the caffeine in yerba mate might reduce the effects of carbamazepine and increase the risk for convulsions.
Yerba mate contains caffeine. Animal research suggests that caffeine can lower the anticonvulsant effects of carbamazepine and can induce seizures when taken in doses above 400 mg/kg. Human research has shown that taking caffeine 300 mg in three divided doses along with carbamazepine 200 mg reduces the bioavailability of carbamazepine by 32% and prolongs the plasma half-life of carbamazepine two-fold in healthy individuals.

Likelihood Possible Evidence B
Cimetidine (Tagamet)

Theoretically, cimetidine might increase the levels and adverse effects of the caffeine contained in yerba mate.
Yerba mate contains caffeine. Cimetidine decreases caffeine clearance by 31% to 42%.

Likelihood Likely Evidence B
Clozapine (Clozaril)

Theoretically, the caffeine in yerba mate might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Yerba mate contains caffeine. Caffeine might increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg per day inhibit clozapine metabolism. Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Although researchers speculate that caffeine might inhibit CYP1A2, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients more sensitive to an interaction between clozapine and caffeine.

Likelihood Possible Evidence B
Dipyridamole (Persantine)

Theoretically, the caffeine in yerba mate might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Yerba mate contains caffeine. Caffeine inhibits dipyridamole-induced vasodilation. Still, some researchers recommend that methylxanthines, such as caffeine, as well as methylxanthine-containing products, should be stopped 24 hours prior to pharmacological stress. Methylxanthines appear more likely to interfere with dipyridamole (Persantine) than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram might increase the levels and adverse effects of the caffeine in yerba mate.
Yerba mate contains caffeine. Disulfiram decreases the rate of caffeine clearance.

Likelihood Probable Evidence D
Diuretic Drugs

Theoretically, the caffeine in yerba mate might increase the risk of hypokalemia when used concomitantly with other diuretics.
Yerba mate contains caffeine. Caffeine, especially in excessive amounts, can reduce potassium levels due to stimulation of the sodium-potassium pump. Diuretics can also cause lower potassium levels.

Likelihood Possible Evidence D
Estrogens

Theoretically, estrogens might increase the levels and adverse effects of the caffeine in yerba mate.
Yerba mate contains caffeine. Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Ethosuximide (Zarontin)

Theoretically, the caffeine in yerba mate might reduce the effects of ethosuximide and increase the risk for convulsion.
Yerba mate contains caffeine. Animal research shows that caffeine 92.4 mg/kg can decrease the anticonvulsant activity of ethosuximide. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Felbamate (Felbatol)

Theoretically, the caffeine in yerba mate might reduce the effects of felbamate and increase the risk for convulsion.
Yerba mate contains caffeine. Animal research shows that a high dose of caffeine 161.7 mg/kg can decreases the anticonvulsant activity of felbamate. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Flutamide (Eulexin)

Theoretically, the caffeine in yerba mate might increase the levels and adverse effects of flutamide.
Yerba mate contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide. However, this effect has not been reported in humans.

Likelihood Possible Evidence D
Fluvoxamine (Luvox)

Theoretically, fluvoxamine might increase the levels and adverse effects of the caffeine in yerba mate.
Yerba mate contains caffeine. Fluvoxamine reduces caffeine metabolism.

Likelihood Probable Evidence D
Lithium

Theoretically, abrupt withdrawal of the caffeine in yerba mate might increase serum lithium levels.
Yerba mate contains caffeine, which has diuretic activity. When abruptly discontinued, it might alter the clearance of lithium. There are two case reports of lithium tremor that worsened upon abrupt coffee withdrawal.

Likelihood Probable Evidence D
Midazolam (Versed)

Theoretically, use of yerba mate with midazolam might increase midazolam metabolite levels and adverse effects.
In vitro research shows that yerba mate extract containing 6.75% chlorogenic acid significantly inhibits the metabolism of midazolam via inhibition of cytochrome P450 3A4 (CYP3A4).

Likelihood Possible Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, the caffeine in yerba mate might increase risk of a hypertensive crisis when used concomitantly with MAOIs.
Yerba mate contains caffeine. Caffeine has been shown to inhibit monoamine oxidase (MAO) A and B in laboratory studies. Concomitant intake of large amounts of caffeine with MAOIs might precipitate a hypertensive crisis. In a case report, a patient that consumed 10-12 cups of caffeinated coffee and took the MAOI tranylcypromine presented with severe hypertension. Hypertension was resolved after the patient switched to drinking decaffeinated coffee.

Likelihood Possible Evidence D
Nicotine

Theoretically, the caffeine in yerba mate might increase risk of hypertension when used concomitantly with nicotine.
Yerba mate contains caffeine. Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly.

Likelihood Probable Evidence D
Pentobarbital (Nembutal)

Theoretically, the caffeine in yerba mate might decrease the effects of pentobarbital.
The caffeine in yerba mate might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

Theoretically, the caffeine in yerba mate might reduce the effects of phenobarbital and increase the risk for convulsions.
Yerba mate contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenobarbital. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Phenylpropanolamine

Theoretically, phenylpropanolamine might increase the risk of hypertension as well as the levels and adverse effects of the caffeine in yerba mate.
Yerba mate contains caffeine. Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure. Phenylpropanolamine also seems to increase caffeine serum levels.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, the caffeine in yerba mate might reduce the effects of phenytoin and increase the risk for convulsions.
Yerba mate contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenytoin. The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence B
Pioglitazone (Actos)

Theoretically, the caffeine in yerba mate might increase the levels and clinical effects of pioglitazone.
Yerba mate contains caffeine. Animal research suggests that caffeine can modestly increase the maximum concentration, area under the curve, and half-life of pioglitazone, and also reduce its clearance. This increased the antidiabetic effects of pioglitazone. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Yerba Mate Extract full monograph & all 43 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

Bacopa monnieri extract8 drug types · 930 drugs

Anticholinergic Drugs

Theoretically, concurrent use might decrease the effectiveness of both agents.
Bacopa seems to inhibit acetylcholinesterase and might increase acetylcholine levels, which could counteract the effects of anticholinergic drugs. Similarly, anticholinergic drugs might counteract the cholinergic effects of bacopa.

Likelihood Possible Evidence D
Cevimeline (Evoxac)

Theoretically, bacopa might increase the effects and adverse effects of cevimeline.
In one case, a 58-year-old female taking cevimeline long-term for Sjogren syndrome experienced hyperhidrosis, malaise, nausea, and tachycardia shortly after taking a single dose of bacopa. Symptoms resolved after two days. Cevimeline is metabolized by cytochrome P450 (CYP) 2D6 and CYP3A4, and researchers theorize that bacopa may have inhibited these isoenzymes. However, it is unclear if bacopa causes clinically significant inhibition of either CYP2D6 or CYP3A4.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, concurrent use of bacopa with other cholinergic drugs might have additive effects.
Bacopa seems to inhibit acetylcholinesterase and might increase acetylcholine levels. Theoretically, this could result in additive cholinergic effects when used with cholinergic drugs.

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

Theoretically, bacopa might increase the levels and adverse effects of CYP1A2 substrates.
Research on the effects of bacopa extracts on CYP1A2 enzymes is conflicting. Some in vitro evidence shows that bacopa extract can moderately and non-competitively inhibit CYP1A2, while other in vitro evidence suggests that any effect is unlikely to be clinically significant.

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

Theoretically, bacopa might increase the levels and adverse effects of CYP2C19 substrates.
In vitro evidence suggests that bacopa extract can moderately and non-competitively inhibit CYP2C19 enzymes. It is not known whether this is clinically significant.

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

Theoretically, bacopa might increase the levels and adverse effects of CYP2C9 substrates.
Research on the effect of bacopa extracts on CYP2C9 enzymes is conflicting. Some in vitro evidence suggests that bacopa extract can moderately and non-competitively inhibit CYP2C9, while other in vitro evidence suggests that any effect is unlikely to be clinically significant.

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

Theoretically, bacopa might increase the levels and adverse effects of CYP3A4 substrates.
Research on the effects of bacopa extracts on CYP3A4 enzymes is conflicting. Some in vitro evidence suggests that bacopa extract can moderately and competitively inhibit CYP3A4, while other in vitro evidence suggests that any effect is unlikely to be clinically significant.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, bacopa might have additive effects when used with thyroid hormone.
Animal research suggests that bacopa increases thyroxine (T4) levels in mice by about 40%.

Likelihood Possible Evidence D
Bacopa monnieri extract full monograph & interactions

Theobromine37 drug types · 661 drugs

Ace Inhibitors (Aceis)

Theoretically, taking cocoa with ACEIs might increase the risk of adverse effects.
Human research shows that dark chocolate can inhibit ACE. Additionally, prolonged angioedema in an elderly patient on an ACE inhibitor was precipitated with intake of diabetic chocolate.

Likelihood Possible Evidence D
Adenosine (Adenocard)

Theoretically, cocoa might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Cocoa contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine does not seem to affect supplemental adenosine because high interstitial levels of adenosine overcome the antagonistic effects of caffeine. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. However, methylxanthines appear more likely to interfere with dipyridamole than adenosine-induced stress testing.

Likelihood Possible Evidence B
Alcohol (Ethanol)

Theoretically, concomitant use might increase levels and adverse effects of caffeine.
Cocoa contains caffeine. Alcohol reduces caffeine metabolism. Concomitant use of alcohol can increase caffeine serum concentrations and the risk of caffeine adverse effects.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, cocoa may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Clinical research shows that intake of cocoa can inhibit platelet adhesion, aggregation, and activity and increase aspirin-induced bleeding time. For patients on dual antiplatelet therapy, cocoa may enhance the inhibitory effect of clopidogrel, but not aspirin, on platelet aggregation.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, taking cocoa with antihypertensive drugs might increase the risk of hypotension.
Clinical research shows that cocoa can modestly decrease blood pressure in hypertensive and normotensive patients.

Likelihood Possible Evidence D
Beta-Adrenergic Agonists

Theoretically, large amounts of cocoa might increase the cardiac inotropic effects of beta-agonists.
Cocoa contains caffeine. Theoretically, large amounts of caffeine might increase cardiac inotropic effects of beta-agonists. A case of atrial fibrillation associated with consumption of large quantities of chocolate in a patient with chronic albuterol inhalation abuse has also been reported.

Likelihood Probable Evidence D
Cytochrome P450 1A2 (Cyp1A2) Inhibitors

Theoretically, concomitant use might increase the levels and adverse effects of caffeine.
Cocoa contains caffeine. Caffeine is metabolized by cytochrome P450 1A2 (CYP1A2),. Theoretically, drugs that inhibit CYP1A2 may decrease the clearance rate of caffeine from cocoa and increase caffeine levels.

Likelihood Possible Evidence D
Dipyridamole (Persantine)

Theoretically, cocoa might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Cocoa contains caffeine. Caffeine may inhibit dipyridamole-induced vasodilation. It is recommended that methylxanthines and methylxanthine-containing products be stopped 24 hours prior to pharmacological stress tests. Methylxanthines appear more likely to interfere with dipyridamole than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram might increase the risk of adverse effects from caffeine.
Cocoa contains caffeine. In human research, disulfiram decreases the rate of caffeine clearance.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, using cocoa with diuretic drugs might increase the risk of hypokalemia.
Cocoa contains caffeine. In excessive amounts, caffeine can reduce potassium levels due to stimulation of the sodium-potassium pump. Diuretics can also cause lower potassium levels.

Likelihood Possible Evidence D
Ephedrine

Theoretically, concomitant use might increase the risk for stimulant adverse effects.
Cocoa contains caffeine. There is evidence that using ephedrine with caffeine might increase the risk of serious life-threatening or debilitating adverse effects such as hypertension, myocardial infarction, stroke, seizures, and death.

Likelihood Possible Evidence D
Estrogens

Theoretically, estrogens might increase the levels and adverse effects of caffeine.
Cocoa contains caffeine. Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Flutamide (Eulexin)

Theoretically, cocoa might increase the levels and adverse effects of flutamide.
Cocoa contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide.

Likelihood Possible Evidence D
Fluvoxamine (Luvox)

Theoretically, fluvoxamine might increase the levels and adverse effects of caffeine.
Cocoa contains caffeine. Fluvoxamine reduces caffeine metabolism.

Likelihood Probable Evidence D
Lithium

Theoretically, abrupt cocoa withdrawal might increase the levels and adverse effects of lithium.
Cocoa contains caffeine. There are two case reports of lithium tremor that worsened upon abrupt coffee withdrawal.

Likelihood Possible Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk of a hypertensive crisis.
Cocoa contains caffeine. Large amounts of caffeine with MAOIs might precipitate a hypertensive crisis.

Likelihood Possible Evidence D
Nicotine

Theoretically, concomitant use might increase the risk of hypertension.
Cocoa contains caffeine. Concomitant use of caffeine and nicotine has been shown to have additive cardiovascular effects, including increased heart rate and blood pressure. Blood pressure was increased by 10.8/12.4 mmHg when the agents were used concomitantly.

Likelihood Probable Evidence B
Pentobarbital (Nembutal)

Theoretically, cocoa might decrease the effects of pentobarbital.
Cocoa contains caffeine. Caffeine might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

Theoretically, cocoa might reduce the effects of phenobarbital and increase the risk for convulsions.
Cocoa contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenobarbital. The exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Phenylpropanolamine

Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.
Cocoa contains caffeine. Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure. Phenylpropanolamine also seems to increase caffeine serum levels.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Theoretically, cocoa might reduce the effects of phenytoin and increase the risk for convulsions.
Cocoa contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenytoin. The effect does not seem to be related to the seizure threshold-lowering effects of caffeine. However, the exact mechanism of this interaction is unclear.

Likelihood Possible Evidence D
Quinolone Antibiotics

Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.
Cocoa contains caffeine. Quinolones (also referred to as fluoroquinolones) decrease caffeine clearance.

Likelihood Probable Evidence B
Riluzole (Rilutek)

Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.
Cocoa contains caffeine. Caffeine and riluzole are both metabolized by cytochrome P450 1A2, and concomitant use might reduce metabolism of one or both agents.

Likelihood Possible Evidence D
Stimulant Drugs

Theoretically, concomitant use might increase stimulant adverse effects.
Cocoa contains caffeine. Concomitant use might increase the risk of stimulant adverse effects.

Likelihood Probable Evidence C
Theophylline

Theoretically, cocoa might increase the levels and adverse effects of theophylline.
Cocoa contains caffeine. Large amounts of caffeine might inhibit theophylline metabolism. Caffeine decreases theophylline clearance 23% to 29%.

Likelihood Probable Evidence B
Theobromine full monograph & all 37 interactions

L-Theanine3 drug types · 565 drugs

Antihypertensive Drugs

Theanine might lower blood pressure, potentiating the effects of antihypertensive drugs.
Animal research shows that theanine can lower blood pressure in spontaneously hypertensive animals. Theoretically, concomitant use of theanine and antihypertensive drugs might potentiate the antihypertensive activity.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, theanine might have additive sedative effects when used in conjunction with CNS depressants. However, it is unclear if this concern is clinically relevant.
Theoretically, theanine may compete with glutamate and/or increase plasma gamma-aminobutyric acid (GABA) levels, which could cause CNS depression. In one clinical study, some subjects taking oral theanine reported drowsiness.

Likelihood Unlikely Evidence D
Serotonergic Drugs

Clinical studies regarding the effects of L-theanine on serotonin levels are conflicting. Some studies suggest it can increase serotonin levels in the brain while others report that it may decrease them. Nevertheless, there have been no reports of l-theanine being a causative agent in serotonergic-related side effects or serotonin syndrome.

Likelihood Unlikely Evidence C
L-Theanine full monograph & interactions

Hordenine HCl3 drug types · 329 drugs

Monoamine Oxidase Inhibitors (Maois)

Hordenine is structurally similar to tyramine In vitro research shows that hordenine is a selective substrate for monoamine oxidase-B in the liver. Theoretically, concomitant use of hordenine with MAOIs might increase blood pressure, potentially leading to a hypertensive crisis.
Some MAOIs include isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate).

Likelihood Possible Evidence D
Stimulant Drugs

Hordenine is structurally similar to N-methyltyramine and synephrine, constituents in bitter orange known to have stimulant properties. Theoretically, taking hordenine with drugs with stimulant properties might increase the risk of hypertension and other adverse cardiovascular effects.
Some of these drugs include amphetamine, caffeine, methylphenidate, pseudoephedrine, and many others.

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

Hordenine weakly inhibits cytochrome P450 2D6 (CYP2D6) enzymes in vitro. Theoretically, hordenine might increase the levels of CYP2D6 substrates.
Some of drugs that are CYP2D6 substrates include amitriptyline (Elavil), clozapine (Clozaril), codeine, desipramine (Norpramin), donepezil (Aricept), fentanyl (Duragesic), flecainide (Tambocor), fluoxetine (Prozac), meperidine (Demerol), methadone (Dolophine), metoprolol (Lopressor, Toprol XL), olanzapine (Zyprexa), ondansetron (Zofran), tramadol (Ultram), trazodone (Desyrel), and others.

Likelihood Possible Evidence D
Hordenine HCl full monograph & interactions

Huperzine A2 drug types · 219 drugs

Anticholinergic Drugs

Theoretically, huperzine A might decrease the effects of anticholinergic drugs.
Huperzine A has acetylcholinesterase (AChE) inhibiting effects. In animal models, huperzine A reversed cognitive deficits induced by scopolamine, an anticholinergic drug.

Likelihood Possible Evidence D
Cholinergic Drugs

Theoretically, concurrent use of huperzine A with cholinergic drugs might increase the effects and side effects of these medications.
Huperzine A can inhibit acetylcholinesterase (AChE) and might cause cumulative effects if used with cholinergic drugs.

Likelihood Possible Evidence B
Huperzine A full monograph & interactions

Phosphatidylserine2 drug types · 219 drugs

Anticholinergic Drugs

Theoretically, phosphatidylserine might decrease the effectiveness anticholinergic drugs.
Phosphatidylserine is thought to increase acetylcholine levels, which could theoretically interfere with the activity of anticholinergic agents.

Likelihood Possible Evidence B
Cholinergic Drugs

Theoretically, phosphatidylserine might have additive effects with cholinergic drugs.
Phosphatidylserine is thought to increase acetylcholine levels, which could theoretically lead to additive cholinergic effects when used with cholinergic drugs.

Likelihood Possible Evidence B
Phosphatidylserine full monograph & interactions

AlphaSize1 drug type · 16 drugs

Scopolamine (Transderm Scop)

Theoretically, alpha-GPC might decrease the effects of scopolamine.
A small clinical study shows that alpha-GPC can partially counteract the attention and memory impairment effects caused by scopolamine given intramuscularly. Whether alpha-GPC can decrease the beneficial anti-motion sickness effects of the scopolamine patch (Transderm Scop) is unclear.

Likelihood Possible Evidence B
AlphaSize full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Red Focus, from the product label.

Red Supplements

See all Red Supplements products
Name
Red Supplements, LLC.
Street Address
1553 N Milwaukee St. Ste. #133
City
Boise
State
ID
ZipCode
83704
Web Address
WWW.REDSUPPLEMENTS.COM
Pharmacist Counseling Corner

Red Focus by Red Supplements: Common Questions

Does Red Focus by Red Supplements interact with any medications?
Yes. Based on its ingredients, Red Focus has a known interaction with 1,498 medications, including 8 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Red Focus 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.

Red Focus label
Go deeper

The Full Monographs Behind Red Focus’s Ingredients

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

Herb & supplement monograph

Theanine

Interacts with 565 drugs

Theanine (usually L-theanine) is an amino acid found naturally in tea leaves that many people take to feel calmer and less stressed without strong drowsiness. Early research suggests it may...

Read the full Theanine monograph → Herb & supplement monograph

Yerba Mate

Interacts with 1,086 drugs

Yerba mate is a caffeine-containing herbal beverage from South America that is widely enjoyed for its stimulating, coffee-like effects. While it is rich in antioxidants and is being studied...

Read the full Yerba Mate monograph → Herb & supplement monograph

Cocoa

Interacts with 661 drugs

Cocoa is rich in plant compounds called flavanols that may modestly support blood vessel function and blood pressure, but most chocolate products are high in sugar, fat, and calories, which...

Read the full Cocoa monograph → Herb & supplement monograph

Huperzine A

Interacts with 219 drugs

Huperzine A is a purified compound from a Chinese clubmoss that acts like a mild cholinesterase inhibitor, similar in mechanism to some prescription Alzheimer's drugs. Some small studies sug...

Read the full Huperzine A monograph → Herb & supplement monograph

Hordenine

Interacts with 329 drugs

Hordenine is a natural alkaloid found in barley and some cacti that is marketed as a stimulant for energy, focus, and fat loss, but solid human evidence for these benefits is lacking. Its sa...

Read the full Hordenine monograph → Herb & supplement monograph

Phosphatidylserine

Interacts with 219 drugs

Phosphatidylserine is a natural fat-like compound found in cell membranes, especially in the brain, and it is sold mainly to support memory and thinking. Some research suggests possible bene...

Read the full Phosphatidylserine monograph → Herb & supplement monograph

Alpha-gpc

Interacts with 16 drugs

Alpha-GPC is a choline-containing compound used mainly for memory, brain health, and as a choline source. There is some evidence it may help cognition in people with dementia, but evidence i...

Read the full Alpha-gpc 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

Bacopa

Interacts with 930 drugs

Bacopa is an Ayurvedic herb most often used for memory and thinking. Some small studies suggest it may modestly help memory when taken regularly for several weeks, but the evidence is limite...

Read the full Bacopa monograph →
Sources

Sources & How We Checked

Red Focus'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 318 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.

Theanine 6 references
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  2. Haskell, C. F., Kennedy, D. O., Milne, A. L., Wesnes, K. A., and Scholey, A. B. The effects of L-theanine, caffeine and their combination on cognition and mood. Biol.Psychol. 2008;77(2):113-122. PubMed
  3. Yokogoshi, H., Kato, Y., Sagesaka, Y. M., Takihara-Matsuura, T., Kakuda, T., and Takeuchi, N. Reduction effect of theanine on blood pressure and brain 5-hydroxyindoles in spontaneously hypertensive rats. Biosci.Biotechnol.Biochem. 1995;59(4):615-618. PubMed
  4. Lyon MR, Kapoor MP, Juneja LR. The effects of L-theanine (Suntheanine®) on objective sleep quality in boys with attention deficit hyperactivity disorder (ADHD): a randomized, double-blind, placebo-controlled clinical trial. Altern Med Rev. 2011;16(4):348-
  5. Hidese S, Ota M, Wakabayashi C, et al. Effects of chronic l-theanine administration in patients with major depressive disorder: an open-label study. Acta Neuropsychiatr 2017;29(2):72-9.
  6. Tsuchiya T, Honda H, Oikawa M, et al. Oral administration of the amino acids cystine and theanine attenuates the adverse events of S-1 adjuvant chemotherapy in gastrointestinal cancer patients. Int J Clin Oncol 2016;21(6):1085-90. PubMed

See these in context on the Theanine monograph →

Yerba Mate 123 references
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  3. Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40. PubMed
  4. Healy DP, Polk RE, Kanawati L, et al. Interaction between oral ciprofloxacin and caffeine in normal volunteers. Antimicrob Agents Chemother 1989;33:474-8. PubMed
  5. Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37:348-50. PubMed
  6. Jefferson JW. Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988;49:72-3.
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  8. Vahedi K, Domingo V, Amarenco P, Bousser MG. Ischemic stroke in a sportsman who consumed MaHuang extract and creatine monohydrate for bodybuilding. J Neurol Neurosurg Psychiatr 2000;68:112-3.
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  10. De Stefani E, Fierro L, Mendilaharsu M, et al. Meat intake, 'mate' drinking and renal cell cancer in Uruguay: a case-control study. Br J Cancer 1998;78:1239-43. PubMed
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See these in context on the Yerba Mate monograph →

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Black Pepper 29 references
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Bacopa 12 references
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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