Major interaction on record — check this product against your medications before combining. Based on 6 of 9 ingredients. Check your meds →
Dietary supplement

Precursor Blackberry Ingredients & Drug Interactions

by Science Powered Supplements

Powder Category: Other Combinations
Most serious interaction: Major
The interaction bottom line Most serious interaction: Major

Precursor Blackberry is a dietary supplement by Science Powered Supplements with 9 active ingredients. Its ingredients are commonly taken for mental focus and alertness, coping with stress, fatigue and sleep loss.Based on those ingredients, 1,135 medications have a known interaction with it, the most serious rated major. The ingredients most likely to interact are Grape seed extract, Agmatine Sulfate, L-Citrulline Malate. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of Precursor Blackberry by Science Powered Supplements

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

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 1 of its 10 active ingredients.
  • “Advanced Pump Matrix” is a proprietary blend — the label gives one combined amount (5,100 mg) without saying how much of each component you get.
  • “elevATP(TM)” is listed as a grouped ingredient — the label doesn't break down how much of each component you get.

Precursor Blackberry contains 10 active ingredients designed to support athletic performance and muscle function. The product includes L-Tyrosine, L-Ornithine Hydrochloride, and L-Citrulline Malate — amino acids that play different roles in energy, muscle recovery, and blood flow.

CarnoSyn (a branded form of beta-alanine) and Agmatine Sulfate are added for workout endurance and muscle support. Grape seed extract and Apple extract provide polyphenol antioxidants.

The formula also contains L-Norvaline, Advanced Pump Matrix, SPS Energy Complex, and elevATP — ingredients we've listed individually in this page where data is available, and blended ingredients whose specifics aren't fully disclosed. The powder also contains several inactive ingredients: natural and artificial flavors, maltodextrin (a carbohydrate filler), beet color, grape skin extract, citric acid, silica, acesulfame potassium, and sucralose.

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: Athletic performance and exercise capacity.
  • We looked for evidence on: Athletic performance, Exercise-induced muscle breakdown, Muscle soreness, Muscle strength, Physical performance, Endurance — and 2 related terms.
  • The strongest evidence on file: Ornithine is rated "Possibly Effective" for Athletic performance (Natural Medicines).
  • Also on file: Beta-alanine is rated "Possibly Effective" for Athletic performance, Physical performance.
  • Also on file: L-citrulline is rated "Possibly Effective" for Athletic performance.

The evidence for this formula's ingredients is mixed. L-Tyrosine is effective for phenylketonuria (PKU) — a genetic condition — and possibly effective for cognitive function and memory, though it's possibly ineffective for athletic performance.

L-Citrulline Malate is possibly effective for athletic performance. CarnoSyn (beta-alanine) is also possibly effective for athletic performance and physical performance.

L-Ornithine Hydrochloride is possibly effective for athletic performance. Grape seed extract is possibly effective for chronic venous insufficiency (leg swelling from poor circulation), but possibly ineffective for allergic rhinitis and weight loss.

For apple extract, agmatine, and the proprietary blend components, the evidence in our data is either insufficient or not established. If you're considering this product for a specific health goal, talk with your pharmacist about whether the science backs it for your situation.

The evidence, ingredient by ingredient Tyrosine Ornithine Beta-alanine L-citrulline Agmatine Grape

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

Most of these ingredients are generally well tolerated in healthy adults, though several carry important caveats. L-Tyrosine commonly causes fatigue, headache, heartburn, and nausea — especially at larger doses.

CarnoSyn (beta-alanine) frequently causes harmless skin tingling and flushing, usually starting on the scalp within 20 minutes and lasting roughly an hour; this is dose-dependent and less noticeable at lower doses. L-Citrulline Malate and Agmatine Sulfate may cause gastrointestinal upset, heartburn, diarrhea, nausea, or dyspepsia.

Grape seed extract can cause abdominal pain, diarrhea, dry mouth, headache, and joint pain — though a rare case of anaphylaxis to grape skin has been reported. Apple extract rarely causes allergic reactions including anaphylaxis.

For pregnancy and breastfeeding: L-Tyrosine, L-Ornithine Hydrochloride, CarnoSyn, L-Citrulline Malate, and Agmatine Sulfate all lack enough safety data — the facts advise against use in pregnancy and breastfeeding. Grape seed extract is likely safe when consumed as whole grapes but is best avoided as a concentrated supplement during pregnancy and breastfeeding due to limited data.

Apple extract has insufficient data; apples as food are considered safe in pregnancy and breastfeeding, but concentrated extracts are not well studied. Talk with your doctor or pharmacist before using this product if you're pregnant, planning pregnancy, or breastfeeding.

Side effects, ingredient by ingredient Tyrosine Ornithine Beta-alanine L-citrulline Agmatine Grape

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?
  • 5 of the 7 matched ingredients can interact with medications — Apple, Grape, Tyrosine, L-citrulline, Agmatine.
  • 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: 1,136 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Check your medications against this product if you take organic anion-transporting polypeptide (OATP) substrates — a Major interaction. Also screen for antihypertensive drugs (blood pressure medications), blood thinners or antiplatelet drugs, antidiabetes medications, thyroid hormones, levodopa (Parkinson medication), phosphodiesterase-5 inhibitors (erectile dysfunction drugs), and liver-metabolizing enzyme substrates (CYP1A2, CYP2D6, CYP3A4, CYP2E1 substrates).

Additionally, cyclosporine and lithium are affected. Use the interaction checker on this page with your exact medications to be sure.

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.

Precursor Blackberry is designed as a pre-workout or athletic performance aid. If you take blood pressure medications, diabetes medications, blood thinners, thyroid medication, levodopa, any heart or erectile dysfunction drugs, immunosuppressants like cyclosporine, or lithium, you'll need to check your specific medications against our interaction tool — the interaction count is high.

People with no medications or only ones we've cleared can consider it, though gastrointestinal side effects and harmless tingling are common. Always talk with your pharmacist before starting, especially if you're pregnant, breastfeeding, or managing a chronic condition.

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

Assessment coverage: 7 of 10 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Feb 25, 2015.

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 Precursor Blackberry, straight from the product label.

Brand Science Powered Supplements
Barcode (UPC) 855710002239
Net contents 7.72 oz.; 219 Gram(s)
Market status On market
Date entered into DSLD Feb 25, 2015
DSLD ID 42498
Product type Other Combinations
Supplement form Powder
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Precursor Blackberry by Science Powered Supplements, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
7.3 Gram(s)
Maximum serving Sizes:
14.6 Gram(s)
Servings per container
30
UPC/BARCODE
855710002239
IngredientAmount% DV
L-Tyrosine0 NP--
L-Ornithine Hydrochloride0 NP--
CarnoSyn0 NP--
L-Citrulline Malate0 NP--
L-Norvaline0 NP--
Agmatine Sulfate0 NP--
Grape seed extract0 NP--
Apple extract0 NP--
Advanced Pump Matrix5100 mg--
SPS Energy Complex1100 mg--
elevATP(TM)0 NP--
Ancient Peat {extract}0 NP--

Other ingredients: Natural & Artificial flavors, Maltodextrin, Beet color, Grape skin extract, Citric Acid, Silica, Acesulfame Potassium, Sucralose

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.
Precautions

Warning: This product is only intended to be consumed by healthy adults 18 years of age or older.

Before using this product consult with your physician if you are using any medication, pregnant or nursing, or if you have any pre-existing medical condition.

Discontinue use and consult your health care professional if you experience any adverse reaction to this product. Do not exceed recommended serving. Do not use if safety seal is broken or missing.

KEEP OUT OF REACH OF CHILDREN.

Formula

This product contains Beta-Alanine and may cause a temporary tingling sensation on your skin.

General Statements

This product contains Beta-Alanine and may cause a temporary tingling sensation on your skin. This is normal. With continued use, the intensity of the sensation will decrease or disappear.

Contents may settle after shipping. Shake container prior to each use to redistribute ingredients.

+ Explosive Pre-Workout Formula + Scientifically Formulated to Maximize Your Gains + Increase Cellular Energy, Pumps, Size, and Power

Brand IP Statement(s)

CarnoSyn(R) trademark and patents owned by Natural Alternatives International, Inc.

SPs Science Powered Supplements(TM)

FDA Disclaimer Statement

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

FDA Statement of Identity

Dietary Supplement

Seals/Symbols

CarnoSyn(TM) Carnosine Synthesizer

Suggested/Recommended/Usage/Directions

USE ONLY AS DIRECTED. On Workout Days: To determine tolerance, begin with one serving (1 scoop) mixed with (6-10 oz.) of water 30-45 minutes before training. After tolerance has been assessed, take one to two servings (1-2 scoops) 30-45 minutes before training.

See for yourself

Precursor Blackberry by Science Powered Supplements label

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

What’s inside

The Ingredients in Precursor Blackberry by Science Powered Supplements

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

Serving size7.3 Gram(s) Dosage formPowder Servings per container30 Amounts shown are per serving.

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

Advanced Pump Matrix

5100 mg per serving

SPS Energy Complex

1100 mg per serving

Other (inactive) ingredients: Natural & Artificial flavors, Maltodextrin, Beet color, Grape skin extract, Citric Acid, Silica, Acesulfame Potassium, Sucralose. These complete the product’s ingredient list but are not active constituents.

Interaction report

Precursor Blackberry by Science Powered Supplements Drug Interactions

Want to check YOUR meds against Precursor Blackberry?

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
1,135Drugs
47 Major 1,067 Moderate 21 Minor

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in Precursor Blackberry 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.

Grape seed extract9 drug types · 910 drugs

Anticoagulant/Antiplatelet Drugs

Theoretically, grape extracts may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
In vitro evidence suggests that grape extracts might decrease platelet aggregation.

Likelihood Possible Evidence D
Cyclosporine (Neoral, Sandimmune)

Ingesting grape juice with cyclosporine can reduce cyclosporine absorption.
A small pharmacokinetic study in healthy young adults shows that intake of purple grape juice 200 mL along with cyclosporine can decrease the absorption of cyclosporine by up to 30% when compared with water. Separate doses of grape juice and cyclosporine by at least 2 hours to avoid this interaction.

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

Theoretically, grape juice might reduce the levels of CYP1A2 substrates.
A small pharmacokinetic study in healthy adults shows that ingestion of 200 mL of grape juice decreases phenacetin plasma levels. This is thought to be due to induction of CYP1A2.

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

Theoretically, grape seed extract may increase the levels of CYP2D6 substrates.
In vitro evidence suggests that grape seed extract might inhibit CYP2D6 enzymes. However, this interaction has not been reported in humans.

Likelihood Possible Evidence D
Cytochrome P450 2E1 (Cyp2E1) Substrates

Theoretically, grape seed extract might increase the levels of CYP2E1 substrates.
In vitro and animal research suggests that grape seed proanthocyanidin extract inhibits CYP2E1 enzymes. However, this interaction has not been reported in humans.

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

It is unclear if grape seed extract inhibits or induces CYP3A4; research is conflicting.
In vitro evidence suggests that grape seed extract might inhibit CYP3A4 enzymes. However, evidence from animal research shows that grape seed extract may induce CYP3A4 in the liver. So far, these interactions have not been reported in humans.

Likelihood Possible Evidence D
Midazolam (Versed)

Theoretically, long-term intake of grape seed extract might decrease the effects of midazolam.
Animal research shows that subchronic ingestions of grape seed extract can increase the elimination of intravenous midazolam by increasing hepatic CYP3A4 activity. Single doses of grape seed extract do not appear to affect midazolam elimination.

Likelihood Possible Evidence D
Phenacetin

Grape juice might decrease phenacetin absorption.
A small pharmacokinetic study in healthy adults shows that ingestion of 200 mL of grape juice decreases phenacetin plasma levels. This is thought to be due to induction of cytochrome P450 1A2 (CYP1A2).

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

It is unclear if grape juice or grape seed extract inhibits CYP2C9; research is conflicting.
In vitro evidence shows that grape seed extract or grape juice might inhibit CYP2C9 enzymes. However, a small pharmacokinetic study in healthy adults shows that drinking 8 ounces of grape juice once does not affect the clearance of flurbiprofen, a probe-drug for CYP2C9 metabolism. The effects of continued grape juice consumption are unclear.

Likelihood Unlikely Evidence D

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

L-Citrulline Malate2 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-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
The maker

Brand information

Manufacturer and brand details for Precursor Blackberry, from the product label.

Science Powered Supplements

See all Science Powered Supplements products
Name
Direct Digital LLC
City
Charlotte
State
NC
ZipCode
28202
Pharmacist Counseling Corner

Precursor Blackberry by Science Powered Supplements: Common Questions

Does Precursor Blackberry by Science Powered Supplements interact with any medications?
Yes. Based on its ingredients, Precursor Blackberry has a known interaction with 1,135 medications, including 47 rated major. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Precursor Blackberry contains 9 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
What does L-Tyrosine do?
L-Tyrosine is an amino acid your body uses to make neurotransmitters and thyroid hormones. It's effective for phenylketonuria (PKU), a genetic condition, and possibly effective for cognitive function and memory. However, it's possibly ineffective for athletic performance specifically.
Will this supplement make me tingle or flush?
Yes, likely — CarnoSyn (beta-alanine) in this formula commonly causes skin tingling and flushing, usually starting on the scalp within 20 minutes of taking it and lasting about an hour. This is harmless and dose-dependent; lower amounts cause it in fewer people and less noticeably.
Can I take this while pregnant or breastfeeding?
Most of the active ingredients in this formula lack enough safety data — the facts advise against use during pregnancy and breastfeeding. Grapes as food are likely safe, but the concentrated grape seed extract here is not well studied. Talk with your doctor or pharmacist for personalized advice.
Is this product safe if I don't take any medications?
For someone with no medications, the main concerns are gastrointestinal side effects (heartburn, nausea, diarrhea) and the common, harmless tingling from beta-alanine. These ingredients are generally well tolerated in healthy adults, though long-term safety for some (like agmatine and beta-alanine at high doses) has not been fully studied.
Does apple extract in this product reduce how my medications work?
Yes — apple extract can significantly lower blood levels of certain medications, especially those using the OATP absorption pathway (like atenolol, fexofenadine, and aliskiren) and can interfere with blood pressure and blood sugar control. Use the interaction checker with your exact medications to see if you're affected.
What is Agmatine Sulfate for?
Agmatine is a compound related to the amino acid arginine. The evidence for it is insufficient for athletic performance, cognitive disorders, anxiety, and other conditions in our data — so we can't say it works for those purposes based on what we hold.

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

Not sure if Precursor Blackberry is safe with your meds?

Our pharmacists answer your medication & supplement questions — free.

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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.

Precursor Blackberry label
Go deeper

The Full Monographs Behind Precursor Blackberry’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

Ornithine

Ornithine is a non-essential amino acid your body makes naturally as part of the urea cycle, which helps remove ammonia. It is sold as a supplement for fatigue, exercise recovery, and sleep,...

Read the full Ornithine 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

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

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

Grape

Interacts with 910 drugs

Grapes and grape products like grape seed extract contain antioxidant compounds such as resveratrol and proanthocyanidins that may support heart and blood vessel health. While the food is he...

Read the full Grape monograph →
Sources

Sources & How We Checked

Precursor Blackberry'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 79 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 →

Ornithine 1 reference
  1. Dietary Supplements: What You Need to Know — NIH Office of Dietary Supplements Source

See these in context on the Ornithine 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 →

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 →

Agmatine 3 references
  1. Piletz JE, Aricioglu F, Cheng JT, et al. Agmatine: clinical applications after 100 years in translation. Drug Discov Today 2013;18(17-18):880-93. PubMed
  2. Keynan O, Mirovsky Y, Dekel S, Gilad VH, Gilad GM. Safety and efficacy of dietary agmatine sulfate in lumbar disc-associated radiculopathy. An open-label, dose-escalating study followed by a randomized, double-blind, placebo-controlled trial. Pain Med 201 PubMed
  3. Shopsin B. The clinical antidepressant effect of exogenous agmatine is not reversed by parachlorophenylalanine: a pilot study. Acta Neuropsychiatr 2013;25(2):113-8. PubMed

See these in context on the Agmatine monograph →

Grape 34 references
  1. Kiesewetter H, Koscielny J, Kalus U, et al. Efficacy of orally administered extract of red vine leaf AS 195 (folia vitis viniferae) in chronic venous insufficiency (stages I-II). A randomized, double-blind, placebo-controlled trial. Arzneimittelforschung
  2. Xiao Dong S, Zhi Ping Z, Zhong Xiao W, et al. Possible enhancement of the first-pass metabolism of phenacetin by ingestion of grape juice in Chinese subjects. Br J Clin Pharmacol 1999;48:638-40. PubMed
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  12. de Lange, D. W., Scholman, W. L., Kraaijenhagen, R. J., Akkerman, J. W., and van de Wiel, A. Alcohol and polyphenolic grape extract inhibit platelet adhesion in flowing blood. Eur.J Clin.Invest 2004;34(12):818-824. PubMed
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  16. Etheridge, A. S., Black, S. R., Patel, P. R., So, J., and Mathews, J. M. An in vitro evaluation of cytochrome P450 inhibition and P-glycoprotein interaction with goldenseal, Ginkgo biloba, grape seed, milk thistle, and ginseng extracts and their constitu
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See these in context on the Grape monograph →

Apple 16 references
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See these in context on the Apple monograph →

Parts of this content are provided by the Therapeutic Research Center, LLC.

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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