Major interaction on record — check this product against your medications before combining. Based on 11 of 12 ingredients. Check your meds →
Dietary supplement

HyperMax Blue Razz Ingredients & Drug Interactions

by Performax Labs

HyperMax Blue Razz label
See full label image
Powder Category: Other Combinations
Most serious interaction: Major
Clinical methodology reviewed by · Updated Sep 30, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking HyperMax Blue Razz 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

HyperMax Blue Razz is a dietary supplement by Performax Labs with 12 active ingredients. Its ingredients are commonly taken for exercise performance, muscle soreness and fatigue, blood flow and circulation.Based on those ingredients, 1,447 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Absorption Enhancement, Citrus aurantium extract, Rauwolfia vomitoria extract. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

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Check Your Meds Against HyperMax Blue Razz by Performax Labs

Ask about any prescription or over-the-counter medication and we check it for interactions with HyperMax Blue Razz by Performax Labs — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of HyperMax Blue Razz by Performax Labs

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 Jul 11, 2026

What’s inside

Partial disclosure
Ingredient Transparency · database check
Partial

Most active ingredients list an amount, but at least one is hidden in a blend or missing.

Why this rating?
  • The label discloses an exact amount for 11 of its 12 active ingredients.
  • “Extreme Pumps and Performance” is listed as a grouped ingredient — the label doesn't break down how much of each component you get.
  • “Extreme Focus and Mood” is listed as a grouped ingredient — the label doesn't break down how much of each component you get.
  • “Extreme Energy Blend” is a proprietary blend — the label doesn't break down how much of each component you get.

HyperMax Blue Razz contains 12 active ingredients designed to support athletic performance, energy, focus, and blood flow. L-Citrulline is included for its possibly effective benefits on athletic performance and is converted in the body to nitric oxide, which aids blood vessel relaxation.

L-Tyrosine supports cognitive function and memory (both possibly effective) and serves as a precursor to thyroid hormone. Beta-Alanine is possibly effective for athletic and physical performance and works by increasing muscle carnosine levels.

Caffeine Anhydrous is likely effective for mental alertness and athletic performance. Agmatine Sulfate, B-Phenylethylamine HCl, and Rauwolfia vomitoria extract are included for focus and stimulant support, though their effectiveness ratings are largely insufficient or unstudied.

Barley is likely effective for cholesterol and heart health, while L-Ornithine L-Aspartate supports the other active ingredients. Black Pepper extract enhances absorption of other compounds.

The product also contains several proprietary blends—Extreme Pumps and Performance, Extreme Focus and Mood, and Extreme Energy Blend—whose component ingredients are listed individually above. No inactive fillers are listed.

Does it work?

Strong 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
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: Pre-workout energy and athletic performance.
  • We looked for evidence on: Athletic performance, Exercise-induced muscle soreness, Exercise-induced muscle breakdown, Fatigue, Headache, Cognitive function — and 3 related terms.
  • The strongest evidence on file: Caffeine is rated "Effective" for Postoperative headache (Natural Medicines).
  • Also on file: Caffeine is rated "Likely Effective" for Athletic performance.
  • Also on file: Caffeine is rated "Possibly Effective" for Postdural puncture headache.

The evidence for this product's performance support is mixed. Caffeine Anhydrous is likely effective for mental alertness and athletic performance at typical doses.

L-Citrulline and Beta-Alanine are both possibly effective for athletic performance, though L-Citrulline's blood pressure effects appear modest in clinical testing. L-Tyrosine is possibly effective for cognitive function and memory.

Barley is likely effective for cholesterol and heart health. For the other ingredients—Agmatine Sulfate, B-Phenylethylamine HCl, Rauwolfia vomitoria extract, and L-Ornithine L-Aspartate—evidence in our data is insufficient to establish effectiveness for athletic performance or focus.

The product's overall performance benefit will depend heavily on the caffeine and well-studied amino acids rather than the less-researched stimulant extracts.

The evidence, ingredient by ingredient L-citrulline Beta-alanine Agmatine L-ornithine-l-aspartate Phenethylamine (pea) Barley Tyrosine Caffeine

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 11 of the 11 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 11 of 11.
  • General safety write-ups exist for 11 of 11.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Most ingredients in this product are generally well tolerated in short-term use, but several carry important cautions. Beta-Alanine commonly causes a harmless tingling sensation (paresthesia), especially on the scalp and face, that typically lasts about an hour.

L-Citrulline and L-Tyrosine can cause gastrointestinal discomfort, heartburn, nausea, and fatigue. Caffeine at higher doses may cause anxiety, insomnia, tremor, and restlessness.

Citrus aurantium and Rauwolfia vomitoria extract are the most concerning: both can raise blood pressure and heart rate, particularly in combination, and may cause dizziness, difficulty concentrating, or rarely serious cardiovascular events. Agmatine may cause diarrhea, nausea, and indigestion.

Black Pepper and Barley are generally safe when used as food but may cause allergic reactions in sensitive individuals. Long-term safety data for most ingredients in this combination is not well studied.

Side effects, ingredient by ingredient L-citrulline Beta-alanine Agmatine L-ornithine-l-aspartate Phenethylamine (pea) Barley Tyrosine Caffeine

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?
  • 9 of the 11 matched ingredients can interact with medications — Barley, Black Pepper, Bitter Orange, Caffeine, Tyrosine, among others.
  • The most serious interaction on file is rated Major.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; immunosuppressants / transplant drugs; diabetes medications; heart-rhythm medications; lithium; Parkinson's medications.
  • For scale: 1,448 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.

Stop and check before using if you take monoamine oxidase inhibitors (MAOIs), antipsychotic drugs, stimulant medications, or levodopa—these carry Major-severity interactions. Major caution is also warranted with ephedrine.

For Moderate interactions, double-check your use if you take blood pressure medications (antihypertensives), diabetes drugs, antiseizure medications (phenobarbital, carbamazepine), antibiotics (especially quinolones), serotonergic antidepressants, midazolam, or beta-blockers. If any of these apply, verify your medications in the interaction checker below before proceeding.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glancePartially disclosed formula with clinical evidence supporting its stated purpose. Major medication interactions have been identified, and safety information is well characterized.

This is a high-stimulant pre-workout formula best suited for healthy adults without blood pressure concerns, heart conditions, or psychiatric medications. If you take any prescription medication—especially blood pressure drugs, antiseizure medications, antidepressants, diabetes drugs, or antipsychotics—check your medications with the tool on this page before using HyperMax Blue Razz.

The combination of caffeine, citrus extract, and Rauwolfia vomitoria makes this product unsuitable during pregnancy or breastfeeding. Talk to your pharmacist before starting, particularly if you have hypertension, cardiac concerns, or take multiple medications.

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

Assessment coverage: 11 of 12 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Dec 22, 2019.

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

At a glance

General information

Key facts about HyperMax Blue Razz, straight from the product label.

Brand Performax Labs
Net contents 400 Gram(s)
Market status On market
Date entered into DSLD Dec 22, 2019
DSLD ID 210037
Product type Other Combinations
Supplement form Powder
Dietary claims / uses 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 HyperMax Blue Razz by Performax Labs, 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:
16 Gram(s)
Maximum serving Sizes:
16 Gram(s)
Servings per container
25
IngredientAmount% DV
L-Citrulline6000 mg--
L-Tyrosine1000 mg--
Beta-Alanine3000 mg--
Caffeine Anhydrous325 mg--
Agmatine Sulfate1000 mg--
Citrus aurantium extract50 mg--
L-Ornithine L-Aspartate1000 mg--
B-Phenylethylamine HCl400 mg--
Extreme Pumps and Performance0 NP--
Extreme Focus and Mood0 NP--
Eria jarensis extract200 mg--
Hordeum vulgare50 mg--
Extreme Energy Blend0 NP--
Rauwolfia vomitoria extract3 mg--
Absorption Enhancement5 mg--
Black Pepper extract0 NP--

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

Pre-Workout Energy Powder

High-stim vasodilator Improve performance and endurance

Formula

Naturally and Artificially flavored

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

See for yourself

HyperMax Blue Razz by Performax Labs label

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

HyperMax Blue Razz 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 HyperMax Blue Razz by Performax Labs

These are the 12 active ingredients this product is made of. Select any to open its full monograph.

Serving size16 Gram(s) Dosage formPowder Servings per container25 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.

Extreme Pumps and Performance

0 NP per serving

Extreme Focus and Mood

0 NP per serving

Extreme Energy Blend

0 NP per serving

Absorption Enhancement

Interacts with
1,020 drugs
5 mg per serving

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 he...

Absorption Enhancement monograph & interactions
Interaction report

HyperMax Blue Razz by Performax Labs Drug Interactions

Want to check YOUR meds against HyperMax Blue Razz?

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
1,447Drugs
231 Major 1,181 Moderate 35 Minor

Ingredients driving the most interactions

Absorption Enhancement 1,020
Citrus aurantium extract 959
Rauwolfia vomitoria extract 840
Caffeine Anhydrous 655
Agmatine Sulfate 258

Individual Drug Interactions

The ingredients in HyperMax Blue Razz interact with 1,447 drugs. Click any drug to see the details.

9 of the 12 ingredients in HyperMax Blue Razz interact with drugs. Each result below shows which ingredient is responsible. Absorption Enhancement Citrus aurantium extract Rauwolfia vomitoria extract Caffeine Anhydrous Agmatine Sulfate B-Phenylethylamine HCl L-Citrulline L-Tyrosine Hordeum vulgare

Each ingredient & the kinds of drugs it affects

For each ingredient in HyperMax Blue Razz 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.

Absorption Enhancement17 drug types · 1,020 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
Absorption Enhancement full monograph & interactions

Citrus aurantium extract13 drug types · 959 drugs

Midazolam (Versed)

Bitter orange might increase blood levels of midazolam.
One small clinical study shows that bitter orange juice can increase midazolam levels, likely through inhibition of cytochrome P450 3A4 (CYP3A4). Theoretically, bitter orange might increase the risk of midazolam-related adverse effects.

Likelihood Probable Evidence B
Monoamine Oxidase Inhibitors (Maois)

Theoretically, taking MAOIs with synephrine-containing bitter orange preparations might increase the hypertensive effects of synephrine, potentially leading to hypertensive crisis.
Bitter orange contains tyramine, octopamine, and synephrine, which are MAO substrates.

Likelihood Probable Evidence D
Antidiabetes Drugs

Theoretically, bitter orange might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Some clinical research shows that drinking a tea containing bitter orange and Indian snakeroot reduces fasting and postprandial glucose levels in patients with type 2 diabetes who are using antidiabetes drugs. However, it is unclear if these effects are due to bitter orange, Indian snakeroot, or the combination. An animal study also shows that p-synephrine in combination with gliclazide , a sulfonylurea, causes an additional 20% to 44% decrease in glucose levels when compared with gliclazide alone.

Likelihood Possible Evidence B
Caffeine

Bitter orange might increase blood pressure and heart rate when taken with caffeine.
Small clinical studies show that taking bitter orange in combination with caffeine can increase blood pressure and heart rate in otherwise healthy normotensive adults. Theoretically, this might increase the risk of serious cardiovascular adverse effects.

Likelihood Possible Evidence B
Colchicine

Bitter orange might affect colchicine levels.
Colchicine is a substrate of P-glycoprotein and cytochrome P450 3A4 (CYP3A4). Bitter orange has been reported to inhibit CYP3A4 and increase levels of CYP3A4 substrates. However, one small clinical study in healthy adults shows that drinking bitter orange juice 240 mL twice daily for 4 days and taking a single dose of colchicine 0.6 mg on the 4th day decreases colchicine peak serum levels by 24%, time to peak serum level by 1 hour, and overall exposure to colchicine by 20%. The clinical significance of this finding is unclear.

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

Bitter orange might increase levels of drugs metabolized by CYP3A4.
Small clinical studies suggest that single or multiple doses of freshly squeezed bitter orange juice 200-240 mL can inhibit CYP3A4 metabolism of drugs, causing increased drug levels and potentially increasing the risk of adverse effects. However, the extent of the effect of bitter orange on CYP3A4-mediated drug interactions is unknown. Some evidence suggests that bitter orange selectively inhibits intestinal CYP3A4, but not hepatic CYP3A4. Its effect on P-glycoprotein, which strongly overlaps with CYP3A4 interactions, is unclear. One small clinical study shows that drinking 8 ounces of freshly squeezed bitter orange juice has no effect on cyclosporine, which seems to be more dependent on hepatic CYP3A4 and P-glycoprotein than intestinal CYP3A4.

Likelihood Possible Evidence B
Dextromethorphan (Robitussin Dm, Others)

Bitter orange might increase blood levels of dextromethorphan.
One small clinical study shows that bitter orange juice increases dextromethorphan levels, likely through cytochrome P450 3A4 (CYP3A4) inhibition. Theoretically, bitter orange might increase the risk for dextromethorphan-related adverse effects.

Likelihood Possible Evidence B
Felodipine (Plendil)

Bitter orange might increase blood levels of felodipine.
One small clinical study shows that bitter orange juice increases felodipine levels, likely through cytochrome P450 3A4 (CYP3A4) inhibition. Theoretically, bitter orange might increase the risk for felodipine-related adverse effects.

Likelihood Probable Evidence B
Indinavir (Crixivan)

Bitter orange might increase blood levels of indinavir.
One small clinical study shows that bitter orange juice slightly increases indinavir levels, but this effect is likely to be clinically insignificant. Bitter orange selectively inhibits intestinal cytochrome P450 3A4 (CYP3A4); however, the metabolism of indinavir seems to be more dependent on hepatic CYP3A4. The effect of bitter orange on other protease inhibitors has not been studied.

Likelihood Possible Evidence B
Qt Interval-Prolonging Drugs

Theoretically, bitter orange might have an additive effect when combined with drugs that prolong the QT interval, potentially increasing the risk of ventricular arrhythmias.
One case report suggests that taking bitter orange in combination with other stimulants such as caffeine might prolong the QT interval in some patients.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Bitter orange juice might increase blood levels of sildenafil.
A small clinical study in healthy adult males shows that drinking freshly squeezed bitter orange juice 250 mL daily for 3 days and taking a single dose of sildenafil 50 mg on the 3rd day increases the peak plasma concentration of sildenafil by 18% and the overall exposure to sildenafil by 44%. Theoretically, this may be due to inhibition of cytochrome P450 3A4 by bitter orange.

Likelihood Probable Evidence B
Stimulant Drugs

Theoretically, bitter orange might increase the risk of hypertension and adverse cardiovascular effects when taken with stimulant drugs.
Bitter orange appears to have stimulant effects.

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

Theoretically, bitter orange might increase levels of drug metabolized by CYP2D6.
In vitro research shows that octopamine, a constituent of bitter orange, weakly inhibits CYP2D6 enzymes. This effect has not been reported in humans.

Likelihood Possible Evidence D
Citrus aurantium extract full monograph & interactions

Rauwolfia vomitoria extract11 drug types · 840 drugs

Antipsychotic Drugs

Theoretically, concomitant use might increase the risk of adverse effects.
Concomitant use of neuroleptics with Rauvolfia vomitoria may potentiate the effects of these drugs and the rauwolfia alkaloids.

Likelihood Probable Evidence D
Levodopa

Theoretically, Rauvolfia vomitoria might reduce the effects of levodopa.
Avoid using Rauvolfia vomitoria with levodopa; concomitant use may reduce drug effectiveness and increase extrapyramidal motor symptoms.

Likelihood Probable Evidence D
Monoamine Oxidase Inhibitors (Maois)

Theoretically, concomitant use might cause additive effects.
Yohimbine, a constituent of Rauvolfia vomitoria, has MAO inhibitory effects. At high doses, yohimbine is a non-selective inhibitor of MAO.

Likelihood Probable Evidence D
Stimulant Drugs

Theoretically, concomitant use might cause additive effects.
Yohimbine, a constituent of Rauvolfia vomitoria, has sympathomimetic effects and increases blood pressure in a dose-dependent manner. Theoretically, taking Rauvolfia vomitoria with stimulant drugs can have additive stimulant and hypertensive effects.

Likelihood Probable Evidence D
Antidiabetes Drugs

Theoretically, taking Rauvolfia vomitoria with antidiabetes drugs might increase the risk of hypoglycemia.
Preliminary clinical research shows that drinking a beverage containing Rauvolfia vomitoria foliage and bitter orange fruit lowers blood glucose levels. Hypoglycemic effects of Rauvolfia vomitoria have also been demonstrated in an animal diabetic model.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, Rauvolfia vomitoria might increase the risk of hypotension.
Rauvolfia vomitoria contains a very small amount of the drug reserpine. Reserpine can reduce both systolic and diastolic blood pressure.

Likelihood Possible Evidence D
Cns Depressants

Theoretically, taking Rauvolfia vomitoria might cause additive sedative effects.
Rauvolfia vomitoria has sedative effects in animal research.

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

Theoretically, Rauvolfia vomitoria might increase the levels and clinical effects of CYP2D6 substrates.
Rauvolfia vomitoria contains small amounts of the drug yohimbine. In vitro research shows that yohimbine inhibits CYP2D6 enzyme activity.

Likelihood Possible Evidence D
Ephedrine

Theoretically, Rauvolfia vomitoria might alter the effects and side effects of ephedrine.
Rauvolfia vomitoria contains resperine, which might reduce indirect-sympathomimetic drug activity. However, another constituent of Rauvolfia vomitoria, yohimbine, has stimulant activity and may increase the risk of adverse effects with ephedrine.

Likelihood Probable Evidence D
Tricyclic Antidepressants (Tcas)

Theoretically, concomitant use might alter the effects of Rauvolfia vomitoria and increase the risk for adverse effects.
A small clinical study in patients taking TCAs for at least 4 weeks shows that receiving doses of intravenous yohimbine, a constituent of Rauvolfia vomitoria, 2.5-20 mg daily for up to 7 days precipitates severe anxiety, agitation, and tremor. Also, concomitant use of TCAs with Rauvolfia vomitoria may decrease the effects of rauwolfia alkaloids.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, combining Rauvolfia vomitoria with antiplatelet or anticoagulant drugs might have additive effects.
Rauvolfia vomitoria contains small amounts of yohimbine. Research in healthy adults shows that taking yohimbine in doses of 8 mg or more seems to inhibit platelet aggregation in vitro by binding to the alpha-2 adrenoceptor. The effects of Rauvolfia vomitoria itself are unclear.

Likelihood Possible Evidence D
Rauwolfia vomitoria extract 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

Agmatine Sulfate2 drug types · 258 drugs

Antidiabetes Drugs

Theoretically, agmatine might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal and in vitro research suggest that agmatine has mild hypoglycemic effects.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, agmatine might increase the risk of hypotension when taken with antihypertensive drugs.
Animal research suggests that agmatine can modestly decrease heart rate and blood pressure.

Likelihood Possible Evidence D
Agmatine Sulfate full monograph & interactions

B-Phenylethylamine HCl2 drug types · 187 drugs

Monoamine Oxidase Inhibitors (Maois)

Theoretically, taking phenethylamine concomitantly with MAOIs may increase adverse effects.
In humans, phenethylamine is oxidized by MAO-B to form the inactive metabolite phenylacetic acid. Animal research shows that administering an MAOI prior to phenethylamine increases the amphetamine-like effects of phenethylamine. However, low-quality clinical research has used phenethylamine with selegiline, an MAOI, with apparent safety.

Likelihood Possible Evidence D
Serotonergic Drugs

Theoretically, combining serotonergic drugs with phenethylamine might increase the risk of serotonergic adverse effects.
Animal research shows that phenethylamine increases levels of serotonin, norepinephrine, and dopamine. Theoretically, combining serotonergic drugs with phenethylamine might increase the risk of additive serotonergic adverse effects, including serotonin syndrome and cerebral vasoconstrictive disorders. However, low-quality clinical research has used phenethylamine with selegiline, a monoamine oxidase inhibitor (MAOI), with apparent safety.

Likelihood Possible Evidence D
B-Phenylethylamine HCl full monograph & interactions

L-Citrulline2 drug types · 178 drugs

Antihypertensive Drugs

Theoretically, concomitant use of L-citrulline with antihypertensive drugs might have additive effects and increase the chance of hypotension.
L-citrulline is converted to L-arginine, which can increase nitric oxide and cause vasodilation. However, a meta-analysis of 5 small clinical studies suggests that taking L-citrulline 3-6 grams daily for 1-8 weeks does not lower blood pressure when compared with control.

Likelihood Possible Evidence B
Phosphodiesterase-5 Inhibitors

Theoretically, concurrent use of phosphodiesterase-5 (PDE-5) inhibitors and L-citrulline might result in additive vasodilation.
L-citrulline is converted to L-arginine, which can increase nitric oxide and cause vasodilation. Theoretically, taking L-arginine with PDE-5 inhibitors might have additive vasodilatory and hypotensive effects. However, in studies evaluating the combined use of L-arginine and sildenafil for erectile dysfunction, hypotension was not reported.

Likelihood Possible Evidence D
L-Citrulline 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

Hordeum vulgare1 drug type · 1 drug

Triclabendazole (Egaten)

Theoretically, barley might decrease the clinical effects of triclabendazole.
Animal research suggests that a diet supplemented with barley can reduce the bioavailability of triclabendazole when taken concomitantly. This effect has not been shown in humans.

Likelihood Possible Evidence D
Hordeum vulgare full monograph & interactions
The maker

Brand information

Manufacturer and brand details for HyperMax Blue Razz, from the product label.

Performax Labs

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Name
Performax Labs
Pharmacist Counseling Corner

HyperMax Blue Razz by Performax Labs: Common Questions

Does HyperMax Blue Razz by Performax Labs interact with any medications?
Yes. Based on its ingredients, HyperMax Blue Razz has a known interaction with 1,447 medications, including 231 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
HyperMax Blue Razz contains 12 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.
Can I take HyperMax Blue Razz if I'm pregnant or breastfeeding?
No. Multiple ingredients in this product lack sufficient safety data during pregnancy, and the stimulant components (caffeine, citrus extract, Rauwolfia vomitoria) are not recommended. The safety data advises against use during pregnancy, and similar caution applies to breastfeeding due to unknown effects on the baby. Talk with your doctor or pharmacist about safer alternatives if you're pregnant or nursing.
What is that tingling sensation I get when I take this?
That's a harmless side effect of Beta-Alanine called paresthesia (a pins-and-needles feeling). It usually starts on the scalp within 20 minutes, spreads to the rest of the body, and lasts about an hour. It's more pronounced at higher doses and is not dangerous—it just feels unusual. Taking a lower dose reduces the sensation.
Why is there Black Pepper extract in a pre-workout drink?
Black Pepper extract contains piperine, which enhances the absorption and bioavailability of other ingredients in the formula, helping your body get more benefit from the amino acids and other active compounds. It acts as an absorption booster.
Is L-Citrulline safe to use if I'm on blood pressure medication?
L-Citrulline may have additive blood pressure-lowering effects when combined with antihypertensive drugs, which could increase the risk of low blood pressure. You should check your specific blood pressure medication in the interaction tool on this page before using HyperMax Blue Razz, and talk with your pharmacist about whether it's safe for you.
Does this product have any fillers or inactive ingredients?
No inactive or filler ingredients are listed for this product—all the contents are active ingredients or proprietary blends.
Can I take HyperMax Blue Razz every day long-term?
Long-term safety data for most of these ingredients combined at supplement doses has not been fully studied. Several ingredients—L-Citrulline, L-Tyrosine, Caffeine, Beta-Alanine, Agmatine Sulfate, and Rauwolfia vomitoria—specifically have limited or unknown long-term safety information. Routine daily use should be discussed with your pharmacist or doctor, especially if you have any heart, blood pressure, or thyroid conditions.

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.

HyperMax Blue Razz label
Go deeper

The Full Monographs Behind HyperMax Blue Razz’s Ingredients

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

Herb & supplement monograph

L-citrulline

Interacts with 178 drugs

L-citrulline is an amino acid that the body turns into L-arginine to help make nitric oxide, which relaxes blood vessels and may improve blood flow. It is popular for exercise performance an...

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

Beta-alanine

Beta-alanine is an amino acid taken mostly by athletes to raise muscle carnosine, which may help buffer acid and reduce fatigue during short, high-intensity exercise. The evidence is moderat...

Read the full Beta-alanine monograph → Herb & supplement monograph

Agmatine

Interacts with 258 drugs

Agmatine is a compound your body makes from the amino acid arginine, and it is sold mainly as a workout and 'pump' supplement. Human evidence for most of its claimed benefits is limited and...

Read the full Agmatine monograph → Herb & supplement monograph

L-ornithine-l-aspartate

L-ornithine-L-aspartate (LOLA) is a combination of two amino acids studied mainly for lowering ammonia in people with liver disease and helping manage hepatic encephalopathy. There is reason...

Read the full L-ornithine-l-aspartate monograph → Herb & supplement monograph

Phenethylamine (pea)

Interacts with 187 drugs

Phenethylamine (PEA) is a natural compound made in the body and found in foods like chocolate; supplements are marketed for mood, focus, and energy. Reliable human research on the supplement...

Read the full Phenethylamine (pea) monograph → Herb & supplement monograph

Barley

Interacts with 1 drug

Barley is a nutritious whole grain that is a good source of soluble fiber called beta-glucan, which has solid evidence for modestly lowering LDL ('bad') cholesterol when eaten regularly. It...

Read the full Barley 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

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

Bitter Orange

Interacts with 959 drugs

Bitter orange is a citrus fruit whose extracts contain synephrine, a mild stimulant often added to weight-loss and energy supplements. Evidence that it works for weight loss or performance i...

Read the full Bitter Orange monograph → Herb & supplement monograph

Rauvolfia Vomitoria

Interacts with 840 drugs

Rauvolfia vomitoria is an African shrub whose root contains powerful alkaloids, including reserpine, that have historically been used for high blood pressure and agitation. Because these com...

Read the full Rauvolfia Vomitoria monograph → Herb & supplement monograph

Black Pepper

Interacts with 1,020 drugs

Black pepper is a common kitchen spice that is generally safe in the amounts used in food. Its extract, piperine, is mostly added to supplements to help the body absorb other ingredients (li...

Read the full Black Pepper monograph →
Sources

Sources & How We Checked

HyperMax Blue Razz'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 413 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.

L-citrulline 8 references
  1. Cheng JW, Balwin SN. L-arginine in the management of cardiovascular diseases. Ann Pharmacother 2001;35:755-64. PubMed
  2. Schwedhelm E, Maas R, Freese R, et al. Pharmacokinetic and pharmacodynamic properties of oral L-citrulline and L-arginine: impact on nitric oxide metabolism. Br J Clin Pharmacol 2008;65:51-9. PubMed
  3. Romero MJ, Platt DH, Caldwell RB, Caldwell RW. Therapeutic use of citrulline in cardiovascular disease. Cardiovasc Drug Rev 2006;24:275-90. PubMed
  4. Balderas-Munoz K, Castillo-Martínez L, Orea-Tejeda A, et al. Improvement of ventricular function in systolic heart failure patients with oral L-citrulline supplementation. Cardiol J 2012;19:612-7. PubMed
  5. Sharif Kashani B, Tahmaseb Pour P, Malekmohammad M, et al. Oral l-citrulline malate in patients with idiopathic pulmonary arterial hypertension and Eisenmenger Syndrome: a clinical trial. J Cardiol 2014;64:231-5. PubMed
  6. Pérez-Guisado J, Jakeman PM. Citrulline malate enhances athletic anaerobic performance and relieves muscle soreness. J Strength Cond Res 2010;24:1215-22. PubMed
  7. Mirenayat MS, Moradi S, Mohammadi H, Rouhani MH. Effect of L-citrulline supplementation on blood pressure: a systematic review and meta-analysis of clinical trials. Curr Hypertens Rep. 2018;20(11):98. PubMed
  8. Xu Z, Liu C, Liu S, Zhou Z. Comparison of efficacy and safety of daily oral L-arginine and PDE5Is alone or combination in treating erectile dysfunction: A systematic review and meta-analysis of randomised controlled trials. Andrologia. 2021:e14007. PubMed

See these in context on the L-citrulline monograph →

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 →

Beta-alanine 13 references
  1. Harris RC, Tallon MJ, Dunnett M, et al. The absorption of orally supplied beta-alanine and its effect on muscle carnosine synthesis in human vastus lateralis. Amino Acids 2006;30:279-89.
  2. Hill CA, Harris RC, Kim HJ, et al. Influence of beta-alanine supplementation on skeletal muscle carnosine concentrations and high intensity cycling capacity. Amino Acids 2007;32:225-33.
  3. Bellinger PM, Minahan CL. The effect of ß-alanine supplementation on cycling time trials of different length. Eur J Sport Sci 2016;16(7):829-36.
  4. Chung W, Shaw G, Anderson ME, et al. Effect of 10 week beta-alanine supplementation on competition and training performance in elite swimmers. Nutrients 2012;4(10):1441-53. PubMed
  5. Glenn JM, Gray M, Stewart R, et al. Incremental effects of 28 days of beta-alanine supplementation on high-intensity cycling performance and blood lactate in masters female cyclists. Amino Acids 2015;47(12):2593-600. PubMed
  6. Gross M, Bieri K, Hoppeler H, Norman B, Vogt M. Beta-alanine supplementation improves jumping power and affects severe-intensity performance in professional alpine skiers. Int J Sport Nutr Exerc Metab 2014;24(6):665-73. PubMed
  7. Howe ST, Bellinger PM, Driller MW, Shing CM, Fell JW. The effect of beta-alanine supplementation on isokinetic force and cycling performance in highly trained cyclists. Int J Sport Nutr Exerc Metab 2013;23(6):562-70. PubMed
  8. Sweeney KM, Wright GA, Glenn Brice A, Doberstein ST. The effect of beta-alanine supplementation on power performance during repeated sprint activity. J Strength Cond Res 2010;24(1):79-87.
  9. Décombaz J, Beaumont M, Vuichoud J, Bouisset F, Stellingwerff T. Effect of slow-release ß-alanine tablets on absorption kinetics and paresthesia. Amino Acids 2012;43(1):67-76. Erratum in: Amino Acids 2013;45(4):1015.
  10. Stellingwerff T, Anwander H, Egger A, et al. Effect of two ß-alanine dosing protocols on muscle carnosine synthesis and washout. Amino Acids 2012;42(6):2461-72. PubMed
  11. da Silva RP, de Oliveira LF, Saunders B, et al. Effects of ß-alanine and sodium bicarbonate supplementation on the estimated energy system contribution during high-intensity intermittent exercise. Amino Acids. 2019;51(1):83-96. PubMed
  12. Varanoske AN, Hoffman JR, Church DD, et al. Comparison of sustained-release and rapid-release ß-alanine formulations on changes in skeletal muscle carnosine and histidine content and isometric performance following a muscle-damaging protocol. Amino Acids. PubMed
  13. Perim P, Gobbi N, Duarte B, et al. Beta-alanine did not improve high-intensity performance throughout simulated road cycling. Eur J Sport Sci 2021. PubMed

See these in context on the Beta-alanine monograph →

Caffeine 236 references
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  2. Harder S, Fuhr U, Staib AH, Wolff T. Ciprofloxacin-caffeine: a drug interaction established using in vivo and in vitro investigations. Am J Med 1989;87:89S-91S. PubMed
  3. Carbo M, Segura J, De la Torre R, et al. Effect of quinolones on caffeine disposition. Clin Pharmacol Ther 1989;45:234-40. PubMed
  4. Healy DP, Polk RE, Kanawati L, et al. Interaction between oral ciprofloxacin and caffeine in normal volunteers. Antimicrob Agents Chemother 1989;33:474-8. PubMed
  5. Mester R, Toren P, Mizrachi I, et al. Caffeine withdrawal increases lithium blood levels. Biol Psychiatry 1995;37:348-50. PubMed
  6. Jefferson JW. Lithium tremor and caffeine intake: two cases of drinking less and shaking more. J Clin Psychiatry 1988;49:72-3.
  7. Joeres R, Klinker H, Heusler H, et al. Influence of mexiletine on caffeine elimination. Pharmacol Ther 1987;33:163-9. PubMed
  8. Vahedi K, Domingo V, Amarenco P, Bousser MG. Ischemic stroke in a sportsman who consumed MaHuang extract and creatine monohydrate for bodybuilding. J Neurol Neurosurg Psychiatr 2000;68:112-3.
  9. Wakabayashi K, Kono S, Shinchi K, et al. Habitual coffee consumption and blood pressure: A study of self-defense officials in Japan. Eur J Epidemiol 1998;14:669-73. PubMed
  10. Hodgson JM, Puddey IB, Burke V, et al. Effects on blood pressure of drinking green and black tea. J Hypertens 1999;17:457-63. PubMed
  11. Rapuri PB, Gallagher JC, Kinyamu HK, Ryschon KL. Caffeine intake increases the rate of bone loss in elderly women and interacts with vitamin D receptor genotypes. Am J Clin Nutr 2001;74:694-700. PubMed
  12. The National Toxicology Program (NTP). Caffeine. Center for the Evaluation of Risks to Human Reproduction (CERHR). Available at: http://cerhr.niehs.nih.gov/common/caffeine.html.
  13. Klebanoff MA, Levine RJ, DerSimonian R, et al. Maternal serum paraxanthine, a caffeine metabolite, and the risk of spontaneous abortion. N Engl J Med 1999;341:1639-44. PubMed
  14. Eskenazi B. Caffeine—filtering the facts. N Engl J Med 1999;341:1688-9. PubMed
  15. Fernandes O, Sabharwal M, Smiley T, et al. Moderate to heavy caffeine consumption during pregnancy and relationship to spontaneous abortion and abnormal fetal growth: a meta-analysis. Reprod Toxicol 1998;12:435-44. PubMed
  16. Pollock BG, Wylie M, Stack JA, et al. Inhibition of caffeine metabolism by estrogen replacement therapy in postmenopausal women. J Clin Pharmacol 1999;39:936-40. PubMed
  17. Nurminen ML, Niittynen L, Korpela R, Vapaatalo H. Coffee, caffeine and blood pressure: a critical review. Eur J Clin Nutr 1999;53:831-9. PubMed
  18. Dews PB, Curtis GL, Hanford KJ, O'Brien CP. The frequency of caffeine withdrawal in a population-based survey and in a controlled, blinded pilot experiment. J Clin Pharmacol 1999;39:1221-32. PubMed
  19. FDA. Proposed rule: dietary supplements containing ephedrine alkaloids. Available at: www.verity.fda.gov (Accessed 25 January 2000).
  20. Briggs GB, Freeman RK, Yaffe SJ. Drugs in Pregnancy and Lactation. 5th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 1998.
  21. Hagg S, Spigset O, Mjorndal T, Dahlqvist R. Effect of caffeine on clozapine pharmacokinetics in healthy volunteers. Br J Clin Pharmacol 2000;49:59-63. PubMed
  22. Tobias JD. Caffeine in the treatment of apnea associated with respiratory syncytial virus infection in neonates and infants. South Med J 2000;93:297-304. DOI
  23. Watson JM, Jenkins EJ, Hamilton P, et al. Influence of caffeine on the frequency and perception of hypoglycemia in free-living patients with type 1 diabetes. Diabetes Care 2000;23:455-9. PubMed
  24. Lloyd T, Johnson-Rollings N, Eggli DF, et al. Bone status among postmenopausal women with different habitual caffeine intakes: a longitudinal investigation. J Am Coll Nutr 2000;19:256-61. PubMed
  25. American Academy of Pediatrics. The transfer of drugs and other chemicals into human milk. Pediatrics 2001;108:776-89. PubMed
  26. Sinclair CJ, Geiger JD. Caffeine use in sports. A pharmacological review. J Sports Med Phys Fitness 2000;40:71-9.
  27. Haller CA, Benowitz NL. Adverse cardiovascular and central nervous system events associated with dietary supplements containing ephedra alkaloids. N Engl J Med 2000;343:1833-8. PubMed
  28. Ali M, Afzal M. A potent inhibitor of thrombin stimulated platelet thromboxane formation from unprocessed tea. Prostaglandins Leukot Med 1987;27:9-13. PubMed
  29. Ardlie NG, Glew G, Schultz BG, Schwartz CJ. Inhibition and reversal of platelet aggregation by methyl xanthines. Thromb Diath Haemorrh 1967;18:670-3. DOI
  30. Ferrini RL, Barrett-Connor E. Caffeine intake and endogenous sex steroid levels in postmenopausal women. The Rancho Bernardo Study. Am J Epidemiol 1996:144:642-4. PubMed
  31. Avisar R, Avisar E, Weinberger D. Effect of coffee consumption on intraocular pressure. Ann Pharmacother 2002;36:992-5.. PubMed
  32. Bell DG, Jacobs I, Ellerington K. Effect of caffeine and ephedrine ingestion on anaerobic exercise performance. Med Sci Sports Exerc 2001;33:1399-403. PubMed
  33. Horner NK, Lampe JW. Potential mechanisms of diet therapy for fibrocystic breast conditions show inadequate evidence of effectiveness. J Am Diet Assoc 2000;100:1368-80. PubMed
  34. Bracken MB, Triche EW, Belanger K, et al. Association of maternal caffeine consumption with decrements in fetal growth. Am J Epidemiol 2003;157:456-66.. PubMed
  35. McGowan JD, Altman RE, Kanto WP Jr. Neonatal withdrawal symptoms after chronic maternal ingestion of caffeine. South Med J 1988;81:1092-4.. PubMed
  36. Massey LK. Is caffeine a risk factor for bone loss in the elderly? Am J Clin Nutr 2001;74:569-70. PubMed
  37. Dreher HM. The effect of caffeine reduction on sleep quality and well-being in persons with HIV. J Psychosom Res 2003;54:191-8.. PubMed
  38. Kockler DR, McCarthy MW, Lawson CL. Seizure activity and unresponsiveness after hydroxycut ingestion. Pharmacotherapy 2001;21:647-51.. PubMed
  39. Schechter MD, Timmons GD. Objectively measured hyperactivity--II. Caffeine and amphetamine effects. J Clin Pharmacol 1985;25:276-80.. PubMed
  40. Nix D, Zelenitsky S, Symonds W, et al. The effect of fluconazole on the pharmacokinetics of caffeine in young and elderly subjects. Clin Pharmacol Ther 1992;51:183. DOI
  41. Infante S, Baeza ML, Calvo M, et al. Anaphylaxis due to caffeine. Allergy 2003;58:681-2. PubMed
  42. Massey LK, Whiting SJ. Caffeine, urinary calcium, calcium metabolism and bone. J Nutr 1993;123:1611-4. PubMed
  43. Nawrot P, Jordan S, Eastwood J, et al. Effects of caffeine on human health. Food Addit Contam 2003;20:1-30. PubMed
  44. May DC, Jarboe CH, VanBakel AB, Williams WM. Effects of cimetidine on caffeine disposition in smokers and nonsmokers. Clin Pharmacol Ther 1982;31:656-61. PubMed
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Bitter Orange 47 references
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Barley 15 references
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Rauvolfia Vomitoria 46 references
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Black Pepper 29 references
  1. Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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