Major interaction on record — check this product against your medications before combining. Based on 5 of 6 ingredients. Check your meds →
Dietary supplement

Lipo-6 Hardcore Ingredients & Drug Interactions

by Nutrex Research

Lipo-6 Hardcore label
See full label image
Capsule Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Lipo-6 Hardcore 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

Lipo-6 Hardcore is a dietary supplement by Nutrex Research with 6 active ingredients. Its ingredients are commonly taken for mental focus and alertness, coping with stress, fatigue and sleep loss.Based on those ingredients, 1,333 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are BioPerine, Caffeine Anhydrous, Toothed Clubmoss Aerial Extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Lipo-6 Hardcore by Nutrex Research

Ask about any prescription or over-the-counter medication and we check it for interactions with Lipo-6 Hardcore by Nutrex Research — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of Lipo-6 Hardcore by Nutrex Research

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Aug 13, 2026

What’s inside

Low disclosure
Ingredient Transparency · database check
Low

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

Why this rating?
  • The label discloses an exact amount for 0 of its 6 active ingredients.
  • “LIPO-6 Hardcore Maximum Fat Burner” is listed as a grouped ingredient — the label gives one combined amount (646.50 mg) without saying how much of each component you get.

Lipo-6 Hardcore contains 6 active ingredients. L-tyrosine is an amino acid that serves as a precursor to neurotransmitters and thyroid hormone.

Caffeine anhydrous is a central nervous system stimulant. Rauwolfia root extract is traditionally used but we hold no interaction data for it.

The product also includes a proprietary blend called LIPO-6 Hardcore Maximum Fat Burner, CaloriBurn GP (derived from grains of paradise), BioPerine (black pepper extract), and toothed clubmoss aerial extract, which contains compounds that may affect nerve signaling. The capsules also contain inactive ingredients: cellulose, stearate, silicon dioxide, and colorants (FD&C Blue #1 and FD&C Red #40).

Does it work?

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

Some clinical evidence supports this product's ingredients for its stated purpose, but it isn't conclusive.

Why this rating?
  • The label markets this product for: Maximum weight loss, fires up metabolism, reduces appetite.
  • We looked for evidence on: Obesity, Metabolic rate, Body composition.
  • The strongest evidence on file: Caffeine is rated "Possibly Effective" for Obesity (Natural Medicines).
  • Also on file: Black Pepper is rated "Insufficient Reliable Evidence To Rate" for Obesity.
  • Also on file: Tyrosine is rated "Insufficient Reliable Evidence To Rate" for Obesity.

Evidence for this product's active ingredients is mixed. L-tyrosine is effective for phenylketonuria (PKU) and possibly effective for cognitive function and memory, though possibly ineffective for athletic performance and lacking reliable evidence for alcohol use disorder and dementia.

Caffeine is effective for neonatal apnea and postoperative headache, likely effective for mental alertness and athletic performance, and possibly effective for bronchopulmonary dysplasia. Black pepper (BioPerine) and toothed clubmoss lack established effectiveness ratings in the data we hold, and CaloriBurn GP has no documented effectiveness ratings.

The evidence, ingredient by ingredient Tyrosine Caffeine Grains Of Paradise Black Pepper Toothed Clubmoss

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 4 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

L-tyrosine is generally well tolerated in healthy adults, but safety data is incomplete—avoid supplemental doses unless your doctor advises otherwise. The most common side effects are fatigue, headache, heartburn, and nausea; higher doses can worsen these.

Caffeine is generally safe in moderate amounts but high doses carry serious risks; limit intake during pregnancy and be aware small amounts pass into breast milk. Common side effects include anxiety, dependence with regular use, diarrhea, insomnia, tremor, and nausea.

Black pepper (BioPerine) is likely safe as a food spice but concentrated supplements warrant caution; it's likely safe during pregnancy and breastfeeding at food levels. Toothed clubmoss aerial extract may cause dizziness, nausea, and sweating, and safety during pregnancy and breastfeeding is not established—avoid it in both.

CaloriBurn GP safety is not well studied; avoid supplement amounts in pregnancy and do not use while breastfeeding.

Side effects, ingredient by ingredient Tyrosine Caffeine Grains Of Paradise Black Pepper Toothed Clubmoss

Meds to double-check

Major interaction found
Known Interaction Concern · database check
Major identified

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

Why this rating?
  • 4 of the 5 matched ingredients can interact with medications — Toothed Clubmoss, Black Pepper, Caffeine, Tyrosine.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; lithium; Parkinson's medications.
  • For scale: 1,334 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.

Before taking Lipo-6 Hardcore, double-check with your doctor or pharmacist if you use ephedrine (Major severity)—the combination carries serious stimulant risks. Also verify if you take barbiturates, anticonvulsants, antipsychotics (especially clozapine), antibiotics (quinolones or rifampin), blood pressure drugs (propranolol), antiretrovirals (nevirapine), seizure medications (phenytoin), immunosuppressants (cyclosporine), cholesterol drugs (atorvastatin), respiratory medications (theophylline), blood vessel dilators (dipyridamole), stomach acid reducers (cimetidine), anticholinergics, or cholinergic drugs (all Moderate severity).

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFormula with limited ingredient disclosure with some supporting evidence for its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

This product is a multi-ingredient fat burner with significant interactions—especially the Major-severity combination of caffeine and ephedrine. If you take any prescription medications, especially for blood pressure, seizures, mood, stomach acid, or infections, talk with your doctor or pharmacist before starting.

Pregnant or breastfeeding women should also check with their healthcare provider first, as several ingredients carry insufficient safety data or specific cautions. Use the medication search tool on this page to verify your own drugs against the full interaction list.

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

Assessment coverage: 5 of 6 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Sep 25, 2023.

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 Lipo-6 Hardcore, straight from the product label.

Brand Nutrex Research
Barcode (UPC) 850005755654
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Sep 25, 2023
DSLD ID 288663
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Women (not pregnant or lactating)
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 Lipo-6 Hardcore by Nutrex Research, 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
UPC/BARCODE
850005755654
IngredientAmount% DV
L-Tyrosine0 NP--
Caffeine Anhydrous0 NP--
Rauwolfia Root Extract0 NP--
LIPO-6 Hardcore Maximum Fat Burner646.5 mg--
CaloriBurn GP0 NP--
BioPerine0 NP--
Toothed Clubmoss Aerial Extract0 NP--

Other ingredients: Cellulose, Stearate, Silicon Dioxide, FD&C Blue #1, FD&C Red #40

Tap any ingredient to jump to its full detail below.

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

Maximum weight loss Fires up metabolism High stimulant energy Helps reduce appetite

Maximum Fat Burner

Precautions

Warning: Do not use if under the age of 18, pregnant or nursing.

Warning: Do not use if under the age of 18, pregnant or nursing.

Never exceed the recommended dosage. Do no consume caffeine, synephrine, yohimbe or any stimulant from other sources, including but not limited to coffee, tea, soda energy drinks, dietary supplements or medications. Do not use longer than 2 months. Follow with a 1 month off-period.

Consult your physician prior to use if you are taking any medication or have any medical condition, including but not limited to, heart disease, psychiatric disorders, difficulty urinating, diabetes, high blood pressure, cardiac arrhythmia, recurrent headaches or enlarged prostate.

Discontinue use 2 weeks prior to surgery. Immediately discontinue use if you experience rapid heartbeat, dizziness, server headaches or shortness of breath. This product contains ingredients that may be banned by some sports organizations.

Keep out of reach of children.

This product is highly potent. Never exceed 1 capsule per serving. Never take more than 2 servings in any 24-hour period. For best results do not take with food. Do not take within 6 hours of sleep.

General Statements

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FDA Statement of Identity

Dietary Supplement

Brand IP Statement(s)

CALORIBURN Caloriburn GP trademark by NNB nutrition. Bioperine is a registered trademark of Sabinsa Corp.

Suggested/Recommended/Usage/Directions

Recommended Use: Take 1 capsule in the morning and 1 capsule in the afternoon. This product is highly potent. Never exceed 1 capsule per serving. Never take more than 2 servings in any 24-hour period. For best results do not take with food. Do not take within 6 hours of sleep. Use daily for a minimum of 30 days.

Regular exercise and proper diet are essential for achieving your weight loss goals. As individuals vary so may results from using this product.

FDA Disclaimer Statement

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

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

See for yourself

Lipo-6 Hardcore by Nutrex Research label

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

Lipo-6 Hardcore 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 Lipo-6 Hardcore by Nutrex Research

These are the 6 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.

LIPO-6 Hardcore Maximum Fat Burner

646.5 mg per serving

Other (inactive) ingredients: Cellulose, Stearate, Silicon Dioxide, FD&C Blue #1, FD&C Red #40. These complete the product’s ingredient list but are not active constituents.

Interaction report

Lipo-6 Hardcore by Nutrex Research Drug Interactions

Want to check YOUR meds against Lipo-6 Hardcore?

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
1,333Drugs
8 Major 1,282 Moderate 43 Minor

Ingredients driving the most interactions

BioPerine 1,019
Caffeine Anhydrous 655
Toothed Clubmoss Aerial Extract 219
L-Tyrosine 21

Individual Drug Interactions

The ingredients in Lipo-6 Hardcore interact with 1,333 drugs. Click any drug to see the details.

4 of the 6 ingredients in Lipo-6 Hardcore interact with drugs. Each result below shows which ingredient is responsible. BioPerine Caffeine Anhydrous Toothed Clubmoss Aerial Extract L-Tyrosine

Each ingredient & the kinds of drugs it affects

For each ingredient in Lipo-6 Hardcore 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.

BioPerine17 drug types · 1,019 drugs

Anticoagulant/Antiplatelet Drugs

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

Likelihood Possible Evidence D
Antidiabetes Drugs

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

Likelihood Possible Evidence D
Atorvastatin (Lipitor)

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

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

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

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

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

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

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

Likelihood Possible Evidence D
Lithium

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

Likelihood Probable Evidence D
Nevirapine (Viramune)

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

Likelihood Probable Evidence D
P-Glycoprotein Substrates

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

Likelihood Possible Evidence D
Pentobarbital (Nembutal)

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

Likelihood Possible Evidence D
Phenytoin (Dilantin)

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

Likelihood Possible Evidence B
Propranolol (Inderal)

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

Likelihood Possible Evidence B
Rifampin (Rifadin)

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

Likelihood Possible Evidence B
Theophylline

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

Likelihood Possible Evidence D
Amoxicillin (Amoxil, Trimox)

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

Likelihood Possible Evidence D
Carbamazepine (Tegretol)

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

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

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

Likelihood Possible Evidence D
BioPerine full monograph & interactions

Caffeine Anhydrous41 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 Anhydrous full monograph & all 41 interactions

Toothed Clubmoss Aerial Extract2 drug types · 219 drugs

Anticholinergic Drugs

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

Likelihood Possible Evidence D
Cholinergic Drugs

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

Likelihood Possible Evidence D
Toothed Clubmoss Aerial Extract 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
The maker

Brand information

Manufacturer and brand details for Lipo-6 Hardcore, from the product label.

Nutrex Research

See all Nutrex Research products
Name
Nutrex Research, Inc.
City
Oviedo
State
FL
ZipCode
32765
Phone Number
1-888-362-8739
Web Address
Nutrex.com
Pharmacist Counseling Corner

Lipo-6 Hardcore by Nutrex Research: Common Questions

Does Lipo-6 Hardcore by Nutrex Research interact with any medications?
Yes. Based on its ingredients, Lipo-6 Hardcore has a known interaction with 1,333 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?
Lipo-6 Hardcore contains 6 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Does this product have caffeine, and how much?
Yes, it contains caffeine anhydrous, which is a concentrated form of caffeine used as a stimulant for alertness and energy. The label should show you the exact dose per capsule. If you're sensitive to caffeine or limit your intake for any reason, check that amount carefully.
What are the most common side effects?
From the caffeine and L-tyrosine content, you might experience anxiety, insomnia, restlessness, headache, nausea, heartburn, or jitteriness. Black pepper may cause a burning aftertaste or stomach upset, and toothed clubmoss may cause dizziness or sweating. Side effects are often dose-dependent and may improve if you lower the dose.
Is it safe to take this while pregnant?
There isn't enough safety data for several ingredients in this product during pregnancy. Caffeine is listed as possibly safe and possibly unsafe depending on the dose, so your doctor needs to weigh the risks. Toothed clubmoss and CaloriBurn GP should be avoided—neither has adequate pregnancy safety information. Talk to your obstetrician or pharmacist before use.
Can I take this while breastfeeding?
Caffeine in small amounts passes into breast milk and is often considered acceptable at moderate intake, though it can affect the baby. Toothed clubmoss and CaloriBurn GP lack sufficient safety data and should be avoided while breastfeeding. Black pepper at food levels appears fine. Check with your doctor or pharmacist about your specific situation.
What does L-tyrosine do in this product?
L-tyrosine is an amino acid your body uses to make neurotransmitters and thyroid hormones. It's effective for phenylketonuria (PKU) and possibly effective for memory and thinking, though the evidence for athletic performance is weak.
What is BioPerine, and why is it in here?
BioPerine is black pepper extract. It's included because the piperine it contains may help your body absorb other ingredients more efficiently. At food spice levels it's well tolerated, though concentrated supplements warrant more caution.

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.

Lipo-6 Hardcore label
Go deeper

The Full Monographs Behind Lipo-6 Hardcore’s Ingredients

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

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

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 → Herb & supplement monograph

Grains Of Paradise

Grains of paradise is a West African spice in the ginger family that people use for digestion, as a spice, and more recently in supplements aimed at metabolism. Early human research suggests...

Read the full Grains Of Paradise 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

Toothed Clubmoss

Interacts with 219 drugs

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

Read the full Toothed Clubmoss monograph →
Sources

Sources & How We Checked

Lipo-6 Hardcore'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 274 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 →

Caffeine 236 references
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Grains Of Paradise 2 references
  1. Dietary Supplements: What You Need to Know — NIH Office of Dietary Supplements Source
  2. Using Dietary Supplements Wisely — NIH NCCIH Source

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Black Pepper 29 references
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See these in context on the Black Pepper monograph →

Toothed Clubmoss 3 references
  1. Budavari S, ed. The Merck Index. 12th ed. Whitehouse Station, NJ: Merck & Co., Inc., 1996.
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See these in context on the Toothed Clubmoss monograph →

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

© 2021 Therapeutic Research Center, LLC

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