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

Knock Out Ingredients & Drug Interactions

by nutra4health

Knock Out label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Knock Out 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

Knock Out is a dietary supplement by nutra4health with 9 active ingredients. Its ingredients are commonly taken for weight loss, fat burning, boosting metabolism.Based on those ingredients, 2,228 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Glucomannan, Green Tea extract, Yohimbe. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against Knock Out by nutra4health

Ask about any prescription or over-the-counter medication and we check it for interactions with Knock Out by nutra4health — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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Computed from our clinical databases

HelloPharmacist Scorecard of Knock Out by nutra4health

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

Evidence for Intended Use
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Not assessable

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

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

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

Why this rating?
  • The label discloses an exact amount for 0 of its 9 active ingredients.
  • “Thermogenesis Blend” is a proprietary blend — the label gives one combined amount (40 mg) without saying how much of each component you get.
  • “Lipogenic Blend” is a proprietary blend — the label gives one combined amount (7 mg) without saying how much of each component you get.
  • “Energy and Focus Blend” is a proprietary blend — the label gives one combined amount (450 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?
  • 8 of the 8 matched ingredients can interact with medications — Glucomannan, Yohimbe, Cola Nut, Green Tea, Caffeine, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications; lithium; Parkinson's medications.
  • For scale: 2,229 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 8 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.

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

Assessment coverage: 8 of 9 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 23, 2021.

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 Knock Out, straight from the product label.

Brand nutra4health
Net contents 60 Capsule(s)
Market status Off market
Date entered into DSLD Jun 23, 2021
DSLD ID 249111
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 Knock Out by nutra4health, 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:
1 Capsule(s)
Maximum serving Sizes:
1 Capsule(s)
Servings per container
60
IngredientAmount% DV
L-Tyrosine0 NP--
L-Carnitine0 NP--
Raspberry Ketones0 NP--
Glucomannan0 NP--
Caffeine0 NP--
Phenylethylamine HCl0 NP--
Kola Nut0 NP--
Thermogenesis Blend40 mg--
Lipogenic Blend7 mg--
Energy and Focus Blend450 mg--
Green Tea extract0 NP--
Yohimbe0 NP--

Other ingredients: Gelatin, Rice Flour, Magnesium Stearate, Silicon Dioxide, FD&C Red #40, Titanium Dioxide

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement take one (1) capsule in the morning. Do not exceed two (2) capsules in a 24-hour period. Do not take past 4 pm. Use for no longer than 8 weeks straight, followed by an off period of at least 2 weeks before resuming use.

Precautions

Warning: Not intended for use by persons under 18 years of age.

Consult a physician before using this product if you have any medical condition including, but not limited to, strokes, high blood pressure, heart, liver, kidney or thyroid disease diabetes, anemia, depression, anxiety, other psychiatric conditions, a family history of these or other medical conditions, or if taking any prescription, OTC and/or other herbal medications.

Formulation

An advanced thermogenic fat-burning formula containing a synergistic blend of nine ingredients to support fat loss in multiple pathways. If taken daily, these ingredients can increase metabolism and fat-burning for up to 8 hours. When combined with exercise and a reduced-calorie diet, Knock Out can help you reach your weightloss goals.

Natural fat burner High impact muscle definition formula

FDA Disclaimer Statement

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

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

Knock Out by nutra4health label

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

Knock Out 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 Knock Out by nutra4health

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

Serving size1 Capsule(s) Dosage formCapsule Servings per container60 Amounts shown are per serving.

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

Thermogenesis Blend

40 mg per serving

Lipogenic Blend

7 mg per serving

Energy and Focus Blend

450 mg per serving

Other (inactive) ingredients: Gelatin, Rice Flour, Magnesium Stearate, Silicon Dioxide, FD&C Red #40, Titanium Dioxide. These complete the product’s ingredient list but are not active constituents.

Interaction report

Knock Out by nutra4health Drug Interactions

Knock Out contains 9 ingredients, and 8 of them have known drug interactions. Altogether they interact with 2,228 medications. Here’s the picture, then you can look up your own drug.

Want to check YOUR meds against Knock Out?

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
2,228Drugs
22 Major 2,155 Moderate 51 Minor

Ingredients driving the most interactions

Glucomannan 2,022
Green Tea extract 1,293
Yohimbe 1,125
Kola Nut 655
Caffeine 655

Individual Drug Interactions

The ingredients in Knock Out interact with 2,228 drugs. Click any drug to see the details.

8 of the 9 ingredients in Knock Out interact with drugs. Each result below shows which ingredient is responsible. Glucomannan Green Tea extract Yohimbe Kola Nut Caffeine Raspberry Ketones L-Tyrosine L-Carnitine

Each ingredient & the kinds of drugs it affects

For each ingredient in Knock Out 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.

Glucomannan1 drug type · 2,022 drugs

Oral Drugs

Theoretically, glucomannan may decrease absorption of drugs taken orally.
Due to its viscosity and bulking effects, there is concern that glucomannan can decrease the absorption of oral drugs. A small clinical study in healthy volunteers shows that taking glyburide 2.5 mg plus glucomannan 3.9 grams with breakfast reduces plasma levels of glyburide when compared with breakfast and glyburide alone. In addition, animal research demonstrates this effect on amoxicillin, but shows increased absorption of metronidazole. This mouse model also demonstrates that metronidazole elimination is prolonged, but amoxicillin elimination is enhanced by 38%; glucomannan may also affect the distribution of some drugs. To avoid changes in absorption, take glucomannan 30-60 minutes after taking oral drugs.

Likelihood Probable Evidence B
Glucomannan full monograph & interactions

Green Tea extract58 drug types · 1,293 drugs

Atorvastatin (Lipitor)

Green tea extract seems to reduce the levels and clinical effects of atorvastatin.
In healthy humans, taking green tea extract 300 mg or 600 mg along with atorvastatin reduces plasma levels of atorvastatin by approximately 24%. The elimination of atorvastatin is not affected. Atorvastatin is a substrate of organic anion-transporting polypeptides (OATPs). Research shows that two of the major catechins found in green tea, epicatechin gallate (ECG) and epigallocatechin gallate (EGCG), inhibit OATPs. Some OATPs are expressed in the small intestine and are responsible for the uptake of drugs and other compounds, which may have resulted in reduced plasma levels of atorvastatin. It is not clear if drinking green tea alters the absorption of atorvastatin.

Likelihood Likely Evidence B
Ephedrine

Theoretically, concomitant use might increase the risk for stimulant adverse effects.
Green tea 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 Probable Evidence D
Nadolol (Corgard)

Green tea seems to reduce the levels and clinical effects of nadolol.
Preliminary clinical research shows that green tea consumption reduces plasma concentrations of nadolol. Compared to a control group, both peak levels and total drug exposure (AUC) of nadolol were reduced by approximately 85% in subjects who drank green tea daily for two weeks. Drinking green tea with nadolol also significantly reduced nadolol's systolic blood pressure lowering effect. Other clinical research shows that a single dose of green tea can affect plasma nadolol levels for at least one hour. Green tea catechins have been shown to inhibit organic anion transporting polypeptides (OATP), one of which, OATP1A2, is involved in the uptake of nadolol in the intestine The interaction is thought to be due primarily to the epigallocatechin gallate (EGCG) content of green tea.

Likelihood Likely Evidence B
5-Fluorouracil

Theoretically, high doses of green tea might increase the effects and side effects of 5-fluorouracil.
Animal research shows that taking green tea in amounts equivalent to about 6 cups daily in humans for 4 weeks prior to receiving a single injection of 5-fluorouracil increases the maximum plasma levels of 5-fluorouracil by about 2.5-fold and the area under the curve by 425%.

Likelihood Possible Evidence D
Adenosine (Adenocard)

Theoretically, green tea might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Green tea contains caffeine. Caffeine is a competitive inhibitor of adenosine at the cellular level. However, caffeine doesn't 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 (Persantine) than adenosine-induced stress testing.

Likelihood Possible Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, green tea may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Conflicting reports exist regarding the effect of green tea on bleeding risk when used with anticoagulant or antiplatelet drugs; however, most evidence suggests that drinking green tea in moderate amounts is unlikely to cause a significant interaction. Green tea contains small amounts of vitamin K, approximately 7 mcg per cup. Some case reports have associated the antagonism of warfarin with the vitamin K content of green tea. However, these reports are rare, and very large doses of green tea (about 8-16 cups daily) appear to be needed to cause these effects. Furthermore, the catechins and caffeine in green tea are reported to have antiplatelet activity.

Likelihood Unlikely Evidence D
Beta-Adrenergic Agonists

Green tea contains caffeine. Theoretically, concomitant use of large amounts of caffeine might increase cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Bortezomib (Velcade)

Theoretically, green tea might interfere with the effects of bortezomib.
In vitro research shows that green tea polyphenols, such as epigallocatechin gallate (EGCG), interact with bortezomib and block its proteasome inhibitory action. This prevents the induction of cell death in multiple myeloma or glioblastoma cancer cell lines. Advise patients taking bortezomib, not to take green tea.

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

Theoretically, green tea might reduce the effects of carbamazepine and increase the risk for convulsions.
Green tea contains caffeine. Animal research suggests that taking 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 2-fold in healthy individuals.

Likelihood Possible Evidence D
Celiprolol (Celicard)

Theoretically, green tea might reduce the levels and clinical effects of celiprolol.
In a small human study, taking green tea daily for 4 days appears to decrease blood and urine levels of celiprolol by at least 98%. This interaction is possibly due to the inhibition of organic anion transporting polypeptide (OATP). Green tea catechins have been shown to inhibit organic anion transporting polypeptides (OATP), one of which, OATP1A2, is found in the intestine The interaction is thought to be due primarily to the epigallocatechin gallate (EGCG) content of green tea.

Likelihood Possible Evidence D
Cimetidine (Tagamet)

Theoretically, concomitant use might increase the effects and adverse effects of caffeine in green tea.
Green tea contains caffeine. Cimetidine can reduce caffeine clearance by 31% to 42%.

Likelihood Likely Evidence B
Clozapine (Clozaril)

Theoretically, green tea might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Animal research suggests that, although green tea extract does not affect the elimination of clozapine, it delays the time to reach peak concentration and reduces the peak plasma levels. Also, concomitant administration of green tea and clozapine might theoretically cause acute exacerbation of psychotic symptoms due to the caffeine in green tea. Caffeine can increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg daily inhibit clozapine metabolism. Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Researchers speculate that caffeine might inhibit CYP1A2. However, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients be more sensitive to the interaction between clozapine and caffeine.

Likelihood Possible Evidence B
Contraceptive Drugs

Theoretically, concomitant use might increase the effects and adverse effects of caffeine found in green tea.
Green tea contains caffeine. Oral contraceptives can decrease caffeine clearance by 40% to 65%.

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

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

Likelihood Possible Evidence D
Dipyridamole (Persantine)

Theoretically, green tea might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Green tea contains caffeine. Caffeine might 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 (Persantine) than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram might increase the risk of adverse effects from caffeine.
In human research, disulfiram decreases the clearance and increases the half-life of caffeine.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, using green tea with diuretic drugs might increase the risk of hypokalemia.
Green tea 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
Estrogens

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

Likelihood Probable Evidence B
Ethosuximide (Zarontin)

Theoretically, green tea might reduce the effects of ethosuximide and increase the risk for convulsions.
Green tea contains caffeine. Animal research suggests 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, green tea might reduce the effects of felbamate and increase the risk for convulsions.
Green tea contains caffeine. Animal research suggests 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
Fexofenadine (Allegra)

Green tea can decrease blood levels of fexofenadine.
Clinical research shows that green tea can significantly decrease blood levels and excretion of fexofenadine. Taking green tea extract with a dose of fexofenadine decreased bioavailability of fexofenadine by about 30%. In vitro, green tea inhibits the cellular accumulation of fexofenadine by inhibiting the organic anion transporting polypeptide (OATP) drug transporter. Research shows that two of the major catechins found in green tea, epicatechin gallate (ECG) and epigallocatechin gallate (EGCG), inhibit OATPs, specifically OATP1A2, OATP1B1, and OATP2B1. In addition, green tea has been shown to reduce the absorption of some drugs that are OATP substrates.

Likelihood Probable Evidence B
Flutamide (Eulexin)

Theoretically, green tea might increase the levels and adverse effects of flutamide.
Green tea contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide. Theoretically, concomitant use of caffeine and flutamide might increase serum concentrations of flutamide and increase the risk adverse effects.

Likelihood Possible Evidence D
Fluvoxamine (Luvox)

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

Likelihood Probable Evidence D
Hepatotoxic Drugs

Theoretically, concomitant use might have additive adverse hepatotoxic effects.
Green tea extract supplements have been linked to several cases of hepatotoxicity and might have additive hepatotoxic effects with other drugs..

Likelihood Unlikely Evidence D
Imatinib (Gleevec)

Theoretically, green tea might reduce the levels and clinical effects of imatinib.
In animal research, a single dose of green tea extract reduces the area under the curve (AUC) of imatinib by up to approximately 64% and its main metabolite N-desmethyl imatinib by up to approximately 81%. This interaction has not been shown in humans. The mechanism of action is unclear but may involve multiple pathways.

Likelihood Possible Evidence D
Green Tea extract full monograph & all 58 interactions

Yohimbe13 drug types · 1,125 drugs

Monoamine Oxidase Inhibitors (Maois)

Concomitant use of MAOIs with yohimbe can result in additive effects.
Yohimbine, a constituent of yohimbe, has MAO inhibitory effects. At high doses, yohimbine is a non-selective inhibitor of MAO.

Likelihood Likely Evidence D
Antihypertensive Drugs

Theoretically, yohimbe might reduce the effects of antihypertensive drugs.
Yohimbine, a constituent of yohimbe, is an alpha-2 adrenoceptor antagonist and has been reported to increase blood pressure in clinical research. Theoretically, concomitant use of yohimbe and antihypertensive drugs can interfere with blood pressure control.

Likelihood Probable Evidence D
Clonidine (Catapres)

Theoretically, yohimbe might precipitate clonidine withdrawal.
Chronic clonidine use can downregulate alpha-2 adrenoreceptors. Animal research and one human case report suggest that concomitant administration of yohimbine, an alpha-2 adrenoceptor antagonist, may precipitate clonidine withdrawal and lead to sympathomimetic toxicity, including hypertensive crisis.

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

CYP2D6 inhibitors may increase the levels and adverse effects of yohimbine, a constituent of yohimbe.
In vitro and clinical research shows that the yohimbe bark constituent, yohimbine, is metabolized by CYP2D6 isoenzymes. Paroxetine, a cytochrome P450 (CYP) 2D6 inhibitor, increases the maximum serum concentration of yohimbine and reduces the clearance of yohimbine compared to yohimbine alone in patients who are extensive CYP2D6 metabolizers..

Likelihood Probable Evidence B
Cytochrome P450 2D6 (Cyp2D6) Substrates

Theoretically, yohimbe might increase the levels and adverse effects of CYP2D6 substrates.
In vitro research suggests that yohimbine, a constituent of yohimbe bark, inhibits CYP2D6 enzyme activity.

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

Theoretically, CYP3A4 inhibitors might increase the levels and adverse effects of yohimbine, a constituent of yohimbe bark.
In vitro and clinical research shows that the yohimbe bark constituent, yohimbine, is metabolized by CYP3A4 enzymes. Theoretically, drugs that inhibit CYP3A4 might increase the levels and adverse effects of yohimbine.

Likelihood Possible Evidence D
Paroxetine (Paxil)

Paroxetine decreases the clearance of yohimbine and may increase its effects.
Paroxetine, a cytochrome P450 (CYP) 2D6 inhibitor, increases the maximum serum concentration of yohimbine by about 350% and reduces the clearance of yohimbine by about 80% compared to yohimbine alone in patients who are extensive CYP2D6 metabolizers. No significant changes in pharmacokinetic parameters of yohimbine were observed with coadministration of paroxetine in patients who are poor CYP2D6 metabolizers.

Likelihood Probable Evidence B
Phenothiazines

Theoretically, using yohimbine with phenothiazines might have additive effects.
Yohimbine, a constituent of yohimbe, has alpha-2 adrenergic antagonist effects. Theoretically, combining it with phenothiazines can cause additive alpha-2 adrenergic antagonism.

Likelihood Possible Evidence D
Stimulant Drugs

Theoretically, taking yohimbe with stimulant drugs can have additive effects.
Yohimbine, a constituent of yohimbe, has sympathomimetic effects and increases blood pressure in a dose-dependent manner. Theoretically, taking yohimbe with stimulant drugs can have additive stimulant and hypertensive effects.

Likelihood Possible Evidence D
Tricyclic Antidepressants (Tcas)

Theoretically, taking yohimbe with TCAs can increase adverse effects.
A small clinical study in patients taking TCAs for at least 4 weeks shows that receiving doses of intravenous yohimbine 2.5-20 mg daily for up to 7 days precipitates severe anxiety, agitation, and tremor. The effects of yohimbe bark itself are unclear; oral yohimbe bark contains 0.6% to 1.38% yohimbine, but it is unclear how much is absorbed.

Likelihood Possible Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, combining yohimbe bark with antiplatelet or anticoagulant drugs might have additive effects; however, this has not been reported in clinical research.
Research in healthy adults shows that taking yohimbine, a constituent of yohimbe bark, in doses of 8 mg or more, seems to inhibit platelet aggregation in vitro by binding to the alpha-2 adrenoceptor. The effects of yohimbe bark itself are unclear; yohimbe bark contains 0.6% to 1.38% yohimbine, but it is unclear how much is absorbed.

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

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

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

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

Likelihood Possible Evidence D
Yohimbe full monograph & interactions

Kola Nut41 drug types · 655 drugs

Adenosine (Adenocard)

Theoretically, cola nut might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
Cola nut 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 (including cola nut) 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
Alcohol (Ethanol)

Theoretically, alcohol might increase the levels and adverse effects of the caffeine in cola nut.
Cola nut contains caffeine. Concomitant use of alcohol and caffeine can increase caffeine serum concentrations and the risk of caffeine adverse effects. Alcohol reduces caffeine metabolism.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, cola nut may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
Cola nut contains caffeine. Caffeine is reported to have antiplatelet activity. This interaction has not been reported in humans.

Likelihood Unlikely Evidence D
Beta-Adrenergic Agonists

Theoretically, the caffeine in cola nut might increase the clinical effects of beta-adrenergic agonists.
Cola nut contains caffeine. Theoretically, concomitant use of large amounts of caffeine might increase the cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Carbamazepine (Tegretol)

Theoretically, cola nut might reduce the effects of carbamazepine and increase the risk for convulsions.
Cola nut contains caffeine. Animal research suggests that taking 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 2-fold in healthy individuals.

Likelihood Possible Evidence D
Clozapine (Clozaril)

Theoretically, cola nut might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
Cola nut contains caffeine. Caffeine can increase the effects and toxicity of clozapine. Caffeine doses of 400-1000 mg daily inhibit clozapine metabolism. Clozapine is metabolized by cytochrome P450 1A2 (CYP1A2). Researchers speculate that caffeine might inhibit CYP1A2. However, there is no reliable evidence that caffeine affects CYP1A2. There is also speculation that genetic factors might make some patients more sensitive to the interaction between clozapine and caffeine.

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

Theoretically, CYP1A2 inhibitors might increase the levels and adverse effects of the caffeine in cola nut.
Cola nut contains caffeine. Caffeine is metabolized by CYP1A2,.

Likelihood Possible Evidence D
Dipyridamole (Persantine)

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

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram might increase the levels and adverse effects of the caffeine in cola nut.
Cola nut contains caffeine. In human research, disulfiram decreases the rate of caffeine clearance.

Likelihood Probable Evidence D
Diuretic Drugs

Theoretically, using cola nut with diuretic drugs might increase the risk of hypokalemia.
Cola nut contains caffeine. In excessive amounts, caffeine can reduce potassium levels due to stimulation of the sodium-potassium pump. Certain diuretics can also lower potassium levels.

Likelihood Possible Evidence D
Ephedrine

Theoretically, concomitant use might increase the risk for stimulant adverse effects.
Cola nut 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 the caffeine in cola nut.
Cola nut contains caffeine. Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Ethosuximide (Zarontin)

Theoretically, cola nut might reduce the effects of ethosuximide and increase the risk for convulsions.
Cola nut contains caffeine. Animal research suggests 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, cola nut might reduce the effects of felbamate and increase the risk for convulsions.
Cola nut contains caffeine. Animal research suggests 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, cola nut might increase the levels and adverse effects of flutamide.
Cola nut contains caffeine. In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide. 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 cola nut.
Cola nut contains caffeine. Fluvoxamine reduces caffeine metabolism.

Likelihood Probable Evidence D
Lithium

Theoretically, abrupt cola nut withdrawal might increase the levels and adverse effects of lithium.
Cola nut contains caffeine. Abrupt caffeine withdrawal can increase serum lithium levels. There are two case reports of lithium tremor that worsened upon abrupt coffee withdrawal.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk of a hypertensive crisis.
Cola nut 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, concomitant use might increase the risk of hypertension.
Cola nut 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, cola nut might decrease the effects of pentobarbital.
Cola nut contains caffeine. Theoretically, caffeine might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

Theoretically, cola nut might reduce the effects of phenobarbital and increase the risk for convulsions.
Cola nut contains caffeine. Animal research suggests that caffeine can decrease the anticonvulsant activity of phenobarbital. However, this effect has not been reported in humans.

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 cola nut.
Cola nut 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, cola nut might reduce the effects of phenytoin and increase the risk for convulsions.
Cola nut 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
Pioglitazone (Actos)

Theoretically, cola nut might increase the levels and clinical effects of pioglitazone.
Cola nut 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
Quinolone Antibiotics

Theoretically, quinolone antibiotics might increase the levels and adverse effects of the caffeine in cola nut.
Cola nut contains caffeine. Quinolones (also called fluoroquinolones) can decrease caffeine clearance by inhibiting cytochrome P450 1A2 (CYP1A2).

Likelihood Probable Evidence B
Kola Nut full monograph & all 41 interactions

Caffeine41 drug types · 655 drugs

Ephedrine

Theoretically, concomitant use might increase the risk for stimulant adverse effects.
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, caffeine might decrease the vasodilatory effects of adenosine and interfere with its use prior to stress testing.
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. 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 (Persantine) than adenosine-induced stress testing.

Likelihood Possible Evidence B
Anticoagulant/Antiplatelet Drugs

Theoretically, caffeine may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
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
Beta-Adrenergic Agonists

Theoretically, large amounts of caffeine might increase the cardiac inotropic effects of beta-agonists.

Likelihood Probable Evidence D
Carbamazepine (Tegretol)

Theoretically, caffeine might reduce the effects of carbamazepine and increase the risk for convulsions.
Animal research suggests that taking 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 2-fold in healthy individuals.

Likelihood Possible Evidence D
Cimetidine (Tagamet)

Theoretically, cimetidine might increase the levels and adverse effects of caffeine.
Cimetidine decreases the rate of caffeine clearance by 31% to 42%.

Likelihood Likely Evidence B
Clozapine (Clozaril)

Caffeine might increase the levels and adverse effects of clozapine and acutely exacerbate psychotic symptoms.
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. In one case report, severe, life-threatening clozapine toxicity and multiorgan system failure occurred in a patient with schizophrenia stabilized on clozapine who consumed caffeine 600 mg daily.

Likelihood Possible Evidence B
Dipyridamole (Persantine)

Theoretically, caffeine might decrease the vasodilatory effects of dipyridamole and interfere with its use prior to stress testing.
Caffeine inhibits 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 (Persantine) than adenosine-induced stress testing.

Likelihood Probable Evidence B
Disulfiram (Antabuse)

Theoretically, disulfiram use might increase the levels and adverse effects of caffeine.
Disulfiram decreases the rate of caffeine clearance.

Likelihood Probable Evidence B
Diuretic Drugs

Theoretically, using caffeine with diuretic drugs might increase the risk of hypokalemia.
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 caffeine.
Estrogen inhibits caffeine metabolism.

Likelihood Probable Evidence B
Ethosuximide (Zarontin)

Theoretically, caffeine might reduce the effects of ethosuximide and increase the risk for convulsions.
Animal research suggests 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, caffeine might reduce the effects of felbamate and increase the risk for convulsions.
Animal research suggests 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, caffeine might increase the levels and adverse effects of flutamide.
In vitro evidence suggests that caffeine can inhibit the metabolism of flutamide. However, this effect has not been reported in humans.

Likelihood Probable Evidence D
Fluvoxamine (Luvox)

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

Likelihood Probable Evidence D
Lithium

Abrupt caffeine withdrawal might increase the levels and adverse effects of lithium.
Caffeine has diuretic activity. When abruptly discontinued, caffeine may alter the clearance of lithium. There are two case reports of lithium tremor that worsened upon abrupt coffee withdrawal and 6 case reports of elevated serum lithium levels after reducing or eliminating caffeine intake. In one case, a male with schizoaffective disorder stabilized on lithium had an elevated lithium level after reducing his caffeine intake by 87%. At a later date, he increased his caffeine intake by 6-fold, resulting in a subtherapeutic lithium level and a recurrence of psychiatric symptoms.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might increase the risk of a hypertensive crisis.
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, concomitant use might increase the risk of hypertension.
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, caffeine might decrease the effects of pentobarbital.
Caffeine might negate the hypnotic effects of pentobarbital.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

Theoretically, caffeine might reduce the effects of phenobarbital and increase the risk for convulsions.
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 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, caffeine might reduce the effects of phenytoin and increase the risk for convulsions.
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
Pioglitazone (Actos)

Theoretically, caffeine might increase the levels and clinical effects of pioglitazone.
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
Quinolone Antibiotics

Theoretically, quinolone antibiotics might increase the levels and adverse effects of caffeine.
Quinolones (also called fluoroquinolones) can decrease caffeine clearance by inhibiting cytochrome P450 1A2 (CYP1A2) enzyme.

Likelihood Probable Evidence B
Riluzole (Rilutek)

Theoretically, concomitant use might increase the levels and adverse effects of both caffeine and riluzole.
Caffeine and riluzole are both metabolized by cytochrome P450 1A2 (CYP1A2), and concomitant use might reduce the metabolism of one or both agents.

Likelihood Possible Evidence D
Caffeine full monograph & all 41 interactions

Raspberry Ketones2 drug types · 174 drugs

Stimulant Drugs

Theoretically, raspberry ketone might increase the risk of adverse cardiovascular effects with stimulant drugs.
Structurally, raspberry ketone resembles synephrine, a known stimulant agent. Heart palpitations, elevated blood pressure, coronary vasospasm, pulseless electrical activity arrest, and resistant polymorphic ventricular tachycardia have been reported in patients taking raspberry ketone.

Likelihood Possible Evidence D
Warfarin (Coumadin)

Theoretically, raspberry ketone might increase warfarin dose requirements.
In one case report, a patient taking warfarin 55 mg per week had a decrease in INR over a period of one month while taking raspberry ketone 250 mg daily. A warfarin dose increase to 70 mg per week was necessary to maintain a therapeutic INR while taking raspberry ketone. The mechanism for this potential interaction is not known.

Likelihood Possible Evidence D
Raspberry Ketones full monograph & interactions

L-Tyrosine2 drug types · 21 drugs

Levodopa

Theoretically, tyrosine might decrease the effectiveness of levodopa.
Tyrosine and levodopa compete for absorption in the proximal duodenum by the large neutral amino acid (LNAA) transport system. Advise patients to separate doses of tyrosine and levodopa by at least 2 hours.

Likelihood Probable Evidence D
Thyroid Hormone

Theoretically, tyrosine might have additive effects with thyroid hormone medications.
Tyrosine is a precursor to thyroxine and might increase levels of thyroid hormones.

Likelihood Probable Evidence D
L-Tyrosine full monograph & interactions

L-Carnitine3 drug types · 19 drugs

Acenocoumarol (Sintrom)

Theoretically, L-carnitine might increase the anticoagulant effects of acenocoumarol.
L-carnitine might enhance the anticoagulant effects of acenocoumarol, an oral anticoagulant similar to warfarin, but shorter-acting. There are at least two case reports of INR elevation with concomitant use. In one case, a 33-year-old male with a previously stable INR had an elevated INR of 4.65 after L-carnitine was started and continued for 10 weeks. INR normalized after discontinuation of the L-carnitine-containing product.

Likelihood Possible Evidence D
Thyroid Hormone

Theoretically, L-carnitine might decrease the effectiveness of thyroid hormone replacement.
L-carnitine appears to act as a peripheral thyroid hormone antagonist by inhibiting entry of thyroid hormone into the nucleus of cells. Taking L-carnitine also seems to diminish some of the symptoms of hyperthyroidism.

Likelihood Probable Evidence B
Warfarin (Coumadin)

Theoretically, L-carnitine might increase the anticoagulant effects of warfarin.
L-carnitine might increase the anticoagulant effects of acenocoumarol, a shorter-acting oral anticoagulant similar to warfarin. There is not enough information to know whether this interaction occurs with L-carnitine and warfarin.

Likelihood Possible Evidence D
L-Carnitine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Knock Out, from the product label.

nutra4health

See all nutra4health products
Name
nutra4health LLC
Street Address
16192 Coastal Hwy
City
Lewes
State
DE
ZipCode
19958
Web Address
www.nutra4.com
Pharmacist Counseling Corner

Knock Out by nutra4health: Common Questions

Does Knock Out by nutra4health interact with any medications?
Yes. Based on its ingredients, Knock Out has a known interaction with 2,228 medications, including 22 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Knock Out 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.

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.

Knock Out label
Go deeper

The Full Monographs Behind Knock Out’s Ingredients

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

Herb & supplement monograph

Raspberry Ketone

Interacts with 174 drugs

Raspberry ketone is a natural aroma compound found in red raspberries that is heavily marketed for weight loss, but there is no good human evidence that it helps people lose weight. Most cla...

Read the full Raspberry Ketone monograph → Herb & supplement monograph

Green Tea

Interacts with 1,293 drugs

Green tea is a popular beverage rich in antioxidants called catechins, and drinking it in normal amounts is considered safe for most people. Concentrated green tea extracts are a different s...

Read the full Green Tea monograph → Herb & supplement monograph

Yohimbe

Interacts with 1,125 drugs

Yohimbe is a West African tree bark that contains yohimbine, a compound mainly promoted for erectile dysfunction and as an aphrodisiac. A prescription form of yohimbine has some evidence for...

Read the full Yohimbe monograph → Herb & supplement monograph

L-carnitine

Interacts with 19 drugs

L-carnitine is a compound your body makes naturally and also gets from foods like meat. It helps cells turn fat into energy, and supplements are most clearly useful for people with a true ca...

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

Cola Nut

Interacts with 655 drugs

Cola nut is a caffeine-containing seed from West Africa used mainly as a natural stimulant for energy and alertness. Most of its effects come from caffeine, and strong human evidence for spe...

Read the full Cola Nut monograph → Herb & supplement monograph

Tyrosine

Interacts with 21 drugs

L-tyrosine is an amino acid your body uses to make brain chemicals like dopamine and norepinephrine. Some studies suggest it may help mental performance during short-term stress, sleep loss,...

Read the full Tyrosine monograph → Herb & supplement monograph

Glucomannan

Interacts with 2,022 drugs

Glucomannan is a soluble fiber from the konjac root that swells into a gel in your stomach, which may help with mild weight loss, constipation, and modestly lowering cholesterol. It is gener...

Read the full Glucomannan monograph → Herb & supplement monograph

Caffeine

Interacts with 655 drugs

Caffeine is a natural stimulant found in coffee, tea, and many other plants and products. In moderate amounts it can boost alertness and reduce tiredness for most healthy adults, but too muc...

Read the full Caffeine monograph →
Sources

Sources & How We Checked

Knock Out'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 742 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.

Tyrosine 4 references
  1. Meyer JS, Welch KM, Deshmukh VD, et al. Neurotransmitter precursor amino acids in the treatment of multi-infarct dementia and Alzheimer's disease. J Amer Geriat Soc 1977;25:289-98.
  2. DiPiro JT, Talbert RL, Yee GC, et al; eds. Pharmacotherapy: A pathophysiologic approach. 4th ed. Stamford, CT: Appleton & Lange, 1999.
  3. Wood DR, Reimherr FW, Wender PH. Amino acid precursors for the treatment of attention deficit disorder, residual type. Psychopharmacol Bull 1985;21:146-9.
  4. van Spronsen FJ, van Rijn M, Bekhof J. Phenylketonuria: tyrosine supplementation in phenylalanine-restricted diets. Am J Clin Nutr 2001;73:153-7. PubMed

See these in context on the Tyrosine monograph →

L-carnitine 41 references
  1. Ellaway CM, Williams K, Leonard H, et al. Rett syndrome: randomized controlled trial of L-carnitine. J Child Neurol 1999;14:162-7. PubMed
  2. Anon. Carnitor (levocarnitine) package insert. Sigma-Tau Pharmaceuticals Inc, Gaithersburg, MD. December 1999.
  3. Cherchi A, Lai C, Angelino F, et al. Effects of L-carnitine on exercise tolerance in chronic stable angina: a multicenter, double-blind, randomized, placebo-controlled, crossover study. Int J Clin Pharmacol Ther Toxicol 1985;23:569-72.
  4. Plioplys AV, Plioplys S. Amantadine and L-carnitine treatment of Chronic Fatigue Syndrome. Neuropsychobiology 1997;35:16-23. PubMed
  5. Benvenga S, Ruggeri RM, Russo A, et al. Usefulness of L-carnitine, a naturally occurring peripheral antagonist of thyroid hormone action, in iatrogenic hyperthyroidism: a randomized, double-blind, placebo-controlled clinical trial. J Clin Endocrinol Meta
  6. Martinez E, Domingo P, Roca-Cusachs A. Potentiation of acenocoumarol action by L-carnitine. J Intern Med 1993;233:94.
  7. Bachmann HU, Hoffmann A. Interaction of food supplement L-carnitine with oral anticoagulant acenocoumarol. Swiss Med Wkly 2004;134:385. PubMed
  8. Evans AM, Fornasini G. Pharmacokinetics of L-carnitine. Clin Pharmacokinet 2003;42:941-67. PubMed
  9. 12761 Benvenga S, Amato A, Calvani M, Trimarchi F. Effects of carnitine on thyroid hormone action. Ann N Y Acad Sci 2004;1033:158-67. PubMed
  10. Ciacci C, Peluso G, Iannoni E, et al. L-Carnitine in the treatment of fatigue in adult celiac disease patients: a pilot study. Dig Liver Dis 2007;39:922-8. PubMed
  11. Cruciani RA, Dvorkin E, Homel P, et al. Safety, tolerability and symptom outcomes associated with L-carnitine supplementation in patients with cancer, fatigue, and carnitine deficiency: a phase I/II study. J Pain Symptom Manage 2006;32:551-9. PubMed
  12. Lebrun C, Alchaar H, Candito M, et al. Levocarnitine administration in multiple sclerosis patients with immunosuppressive therapy-induced fatigue. Mult Scler 2006;12:321-4. PubMed
  13. Malaguarnera M, Cammalleri L, Gargante MP, et al. L-Carnitine treatment reduces severity of physical and mental fatigue and increases cognitive functions in centenarians: a randomized and controlled clinical trial. Am J Clin Nutr 2007;86:1738-44. PubMed
  14. Mantovani G, Maccio A, Madeddu C, et al. Randomized phase III clinical trial of five different arms of treatment in 322 patients with cancer cachexia. Oncologist 2010;15:200-11.
  15. Angelova-Fischer I, Rippke F, Fischer TW, Neufang G, Zillikens D. A double-blind, randomized, vehicle-controlled efficacy assessment study of a skin care formulation for improvement of mild to moderately severe acne. J Eur Acad Dermatol Venereol. 2013 Jul PubMed
  16. Hatamkhani S, Khalili H, Karimzadeh I, Dashti-Khavidaki S, Abdollahi A, Jafari S. Carnitine for prevention of antituberculosis drug-induced hepatotoxicity: a randomized, clinical trial. J Gastroenterol. Hepatol. 2014 May;29(5):997-1004. PubMed
  17. Boehm G, Stahl B. Oligosaccharides from milk. J Nutr 2007;137(3 Suppl 2):847S-849S.
  18. Van Oudheusden, L. J. and Scholte, H. R. Efficacy of carnitine in the treatment of children with attention-deficit hyperactivity disorder. Prostaglandins Leukot.Essent.Fatty Acids 2002;67(1):33-38. PubMed
  19. Derosa, G., Cicero, A. F., Gaddi, A., Mugellini, A., Ciccarelli, L., and Fogari, R. The effect of L-carnitine on plasma lipoprotein(a) levels in hypercholesterolemic patients with type 2 diabetes mellitus. Clin Ther 2003;25(5):1429-1439. PubMed
  20. Foitzik, K., Hoting, E., Heinrich, U., Tronnier, H., and Paus, R. Indications that topical L-carnitin-L-tartrate promotes human hair growth in vivo. J Dermatol.Sci 2007;48(2):141-144. PubMed
  21. Kumar, A., Singh, R. B., Saxena, M., Niaz, M. A., Josh, S. R., Chattopadhyay, P., Mechirova, V., Pella, D., and Fedacko, J. Effect of carni Q-gel (ubiquinol and carnitine) on cytokines in patients with heart failure in the Tishcon study. Acta Cardiol. 20
  22. Cruciani, R. A., Dvorkin, E., Homel, P., Culliney, B., Malamud, S., Lapin, J., Portenoy, R. K., and Esteban-Cruciani, N. L-carnitine supplementation in patients with advanced cancer and carnitine deficiency: a double-blind, placebo-controlled study. J Pa PubMed
  23. Malaguarnera, M., Vacante, M., Avitabile, T., Malaguarnera, M., Cammalleri, L., and Motta, M. L-Carnitine supplementation reduces oxidized LDL cholesterol in patients with diabetes. Am J Clin.Nutr 2009;89(1):71-76. PubMed
  24. Alvarez, T. M., Guardiola, P. D., Roldan, J. O., Elviro, R., Wevers, R., and Guijarro, G. [Primary trimethylaminuria: the fish odor syndrome]. Endocrinol.Nutr. 2009;56(6):337-340.
  25. Wu, Z. M., Lu, X., Wang, Y. W., Sun, J., Tao, J. W., Yin, F. H., and Cheng, H. J. [Short-term medication of L-carnitine before intracytoplasmic sperm injection for infertile men with oligoasthenozoospermia]. Zhonghua Nan.Ke.Xue 2012;18(3):253-256.
  26. Tarighat, Esfanjani A., Mahdavi, R., Ebrahimi, Mameghani M., Talebi, M., Nikniaz, Z., and Safaiyan, A. The effects of magnesium, L-carnitine, and concurrent magnesium-L-carnitine supplementation in migraine prophylaxis. Biol.Trace Elem.Res 2012;150(1-3): PubMed
  27. DiNicolantonio, J. J., Lavie, C. J., Fares, H., Menezes, A. R., and O'Keefe, J. H. L-carnitine in the secondary prevention of cardiovascular disease: systematic review and meta-analysis. Mayo Clin Proc. 2013;88(6):544-551. PubMed
  28. Huang, W. W., Wang, M. Y., Shi, H. M., Peng, Y., Peng, C. S., Zhang, M., Li, Y., Lu, J., and Li, X. B. Comparative study of bioactive constituents in crude and processed Glycyrrhizae radix and their respective metabolic profiles in gastrointestinal tract
  29. Madsen KL, Preisler N, Orngreen MC, Andersen SP, Olesen JH, Lund AM, Vissing J. Patients with medium-chain acyl-coenzyme a dehydrogenase deficiency have impaired oxidation of fat during exercise but no effect of L-carnitine supplementation. J Clin Endocri
  30. Prohaska ES, Muzyk AJ, Rivelli SK. Levocarnitine-induced hypophosphatemia in a hemodialysis patient with acute valproic acid toxicity. J Neuropsychiatry Clin Neurosci. 2012 Winter;24(1):E18-9. PubMed
  31. Shang R, Sun Z, Li H. Effective dosing of L-carnitine in the secondary prevention of cardiovascular disease: a systematic review and meta-analysis. BMC Cardiovasc Disord. 2014 Jul 21;14:88. PubMed
  32. Zhang JJ, Wu ZB, Cai YJ, Ke B, Huang YJ, Qiu CP, Yang YB, Shi LY, Qin J. L-carnitine ameliorated fasting-induced fatigue, hunger, and metabolic abnormalities in patients with metabolic syndrome: a randomized controlled study. Nutr J. 2014 Nov 26;13:110. PubMed
  33. Koeth RA, Wang Z, Levison BS, Buffa JA, Org E, Sheehy BT, Britt EB, Fu X, Wu Y, Li L, Smith JD, DiDonato JA, Chen J, Li H, Wu GD, Lewis JD, Warrier M, Brown JM, Krauss RM, Tang WH, Bushman FD, Lusis AJ, Hazen SL. Intestinal microbiota metabolism of L-carn
  34. Jun DW, Kim BI, Cho YK, Kim HJ, Kwon YO, Park SY, Han SY, Baek YH, Jung YJ, Kim HY, Kim W, Heo J, Woo HY, Hwang SG, Rim KS, Choi JY, Bae SH, Lee YS, Lim YS,Cheong JY, Cho SW, Lee BS, Kim SH, Sohn JH, Kim TY, Paik YH, Kim JK, Lee KS. Efficacy and safety of
  35. An JH, Kim YJ, Kim KJ, et al. L-carnitine supplementation for the management of fatigue in patients with hypothyroidism on levothyroxine treatment: a randomized, double-blind, placebo-controlled trial. Endocr J. 2016;63(10):885-95. PubMed
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See these in context on the Caffeine monograph →

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See these in context on the Cola Nut monograph →

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