Interactions on record — worth a quick check against your medications. Based on 6 of 7 ingredients. Check your meds →
Dietary supplement

Muscle Synergy Ingredients & Drug Interactions

by Beverly International

Muscle Synergy label
See full label image
Tablet Or Pill Category: Other Combinations
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 16, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking Muscle Synergy 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: Moderate

Muscle Synergy is a dietary supplement by Beverly International with 7 active ingredients. Its ingredients are commonly taken for high blood pressure, erectile dysfunction, athletic performance.Based on those ingredients, 747 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Niacin, L-Arginine, L-Citrulline. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Muscle Synergy by Beverly International

Ask about any prescription or over-the-counter medication and we check it for interactions with Muscle Synergy by Beverly International — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Muscle Synergy by Beverly International

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

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 7 of its 7 active ingredients.
  • No proprietary blends here — you can verify the dose of every single component.

Muscle Synergy contains 7 active ingredients. The main ones are L-arginine and L-citrulline, amino acids that support blood vessel function and circulation.

L-glycine and L-ornithine hydrochloride are additional amino acids with roles in muscle and nervous system support. Creatine monohydrate is a compound that helps muscles produce energy during exercise.

Niacin (a B vitamin) supports energy metabolism. The product also contains myHMB, though we hold no interaction data for it.

The remaining ingredients are inactive fillers and binders that hold the tablet together.

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: Muscle size, strength and exercise performance.
  • We looked for evidence on: Athletic performance, Muscle strength, Physical performance, Muscle breakdown, Muscle pump, Vascularity — and 1 related terms.
  • The strongest evidence on file: Ornithine is rated "Possibly Effective" for Athletic performance (Natural Medicines).
  • Also on file: Creatine is rated "Possibly Effective" for Athletic performance, Muscle strength.
  • Also on file: L-citrulline is rated "Possibly Effective" for Athletic performance.

The evidence for Muscle Synergy's ingredients is mixed. L-citrulline and L-ornithine are rated possibly effective for athletic performance.

Creatine monohydrate is rated possibly effective for muscle strength and athletic performance, and possibly effective for sarcopenia (age-related muscle loss). L-glycine is rated possibly effective for schizophrenia, though that's not the product's stated purpose.

For many uses — like cardiovascular health, heart failure, and diabetes control — the evidence in our data is insufficient to rate. Niacin is rated likely effective for pellagra (a nutrient-deficiency disease) and possibly effective for metabolic syndrome and certain lipid disorders, but evidence for its role in muscle support is not established in the data we hold.

The evidence, ingredient by ingredient L-arginine L-citrulline Glycine Ornithine Creatine Niacin

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

L-arginine and L-citrulline are generally well tolerated short-term, but both can lower blood pressure and neither should be used without medical guidance — long-term safety is not fully studied. Common side effects from L-arginine include abdominal pain, bloating, nausea, diarrhea, headache, insomnia, and flushing.

L-citrulline may cause gastrointestinal discomfort and heartburn. L-glycine is generally well tolerated at typical doses but can rarely cause mild sedation, irritability, insomnia, fatigue, or gastrointestinal upset.

Creatine monohydrate is generally well tolerated but may cause dehydration, diarrhea, gastrointestinal upset, muscle cramps, and water retention; those with kidney problems should be careful. Niacin at high supplemental doses commonly causes flushing and gastrointestinal complaints, and can rarely cause liver problems or muscle damage.

L-ornithine hydrochloride is generally well tolerated short-term but long-term safety is not well studied. For pregnancy: L-citrulline, L-ornithine, creatine, and myHMB data advise avoiding them — not enough safety information.

L-arginine is rated possibly safe, and niacin is rated likely safe at normal prenatal-vitamin doses. For breastfeeding: L-citrulline, L-ornithine, creatine, and niacin advise avoiding supplements.

L-glycine and L-arginine have insufficient data — talk to your doctor or pharmacist.

Side effects, ingredient by ingredient L-arginine L-citrulline Glycine Ornithine Creatine Niacin

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 4 of the 6 matched ingredients can interact with medications — L-arginine, Niacin, Glycine, L-citrulline.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; diabetes medications.
  • For scale: 748 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking Muscle Synergy, check with your pharmacist if you take any blood pressure medications (including ACE inhibitors, ARBs, or other antihypertensives), blood thinners (anticoagulants or antiplatelets), potassium-sparing diuretics, diabetes drugs, statins, sildenafil or other erectile dysfunction medications, clozapine (an antipsychotic), gout medications, bile acid sequestrants, or drugs that affect the liver. The severity of these interactions is Moderate across the board.

All six of these drug types carry Moderate-severity risks from one or more ingredients in this product.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with some supporting evidence for its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

This product is aimed at people looking to support muscle performance and recovery, but it's not a simple multivitamin. Because several ingredients can lower blood pressure, affect blood clotting, or alter blood-sugar and potassium levels, anyone on medications — especially for blood pressure, heart disease, diabetes, or clotting — should check with their pharmacist before starting.

The long-term safety profile is not fully established for most ingredients. If you have kidney problems or take clozapine, this product requires special caution.

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

Assessment coverage: 6 of 7 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 25, 2025.

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 Muscle Synergy, straight from the product label.

Brand Beverly International
Barcode (UPC) 857254000559
Net contents 240 Tablet(s)
Market status On market
Date entered into DSLD Jun 25, 2025
DSLD ID 332849
Product type Other Combinations
Supplement form Tablet Or Pill
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years)
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for Muscle Synergy by Beverly International, 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 Tablet(s)
Maximum serving Sizes:
16 Tablet(s)
Servings per container
15
UPC/BARCODE
857254000559
IngredientAmount% DV
L-Arginine7000 mg--
L-Citrulline1600 mg--
L-Glycine1200 mg--
L-Ornithine Hydrochloride1020 mg--
Creatine Monohydrate3000 mg--
Niacin200 mg1250%
myHMB3000 mg--

Other ingredients: Dicalcium Phosphate, Microcrystalline Cellulose, Stearic Acid, Croscarmellose Sodium, Pharmaceutical Glaze, Magnesium Stearate, Silicon Dioxide, Hydroxypropyl Methylcellulose, Gum Acacia, Hydroxypropyl Cellulose, Wax, Micronized, Talc

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.
Formula

Muscle Synergy tablets are used by natural physique athletes who are striving to achieve more dramatic muscle pumps and maximize exercise-induced gains in muscle size and strength.

Muscle pump, size & strength maximizing tablets w/HMB

Suggested/Recommended/Usage/Directions

Use: Take 16 tablets daily.

Try this trick for legendary pumps and vascularity: Take Muscle Synergy 2x daily to stay pumped all day. Stack it with Quadracarn for dramatic vascularity.

Formulation

Muscle Synergy is perfect if you're 40 or over and trying to get your physique back; your training needs a kickstart; you're a hard gainer; or you have difficulty getting pumps during workouts.

100% money-back guarantee If you are not 100% satisfied after using this product for 60 days, then we will refund your money. No questions asked.

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.

General Statements

Questions or comments? Call 800-781-3475 or email [email protected]

Brand IP Statement(s)

Beverly International 1967

Nutritional uses of Calcium Beta-Hydroxy Beta-Methylbutyrate Monohydrate myHMB are licensed to Beverly Inernational Nutrition, Inc under U.S. Patent #6,103,764. Use of the trademark myHMB is licensed from Metabolic Technologies.

FDA Statement of Identity

Dietary Supplement

Precautions

Warning: Consult your physician prior to using this product if you are: under 18 years of age; pregnant; nursing; trying to become pregnant; taking medication; or have a medical condition.

Warning: Consult your physician prior to using this product if you are: under 18 years of age; pregnant; nursing; trying to become pregnant; taking medication; or have a medical condition. Keep out of reach of children.

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

See for yourself

Muscle Synergy by Beverly International label

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

Muscle Synergy 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 Muscle Synergy by Beverly International

These are the 7 active ingredients this product is made of. Select any to open its full monograph.

Serving size16 Tablet(s) Dosage formTablet Or Pill Servings per container15 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.

L-Arginine

Interacts with
403 drugs
7000 mg per serving

L-arginine is an amino acid that the body uses to make nitric oxide, a substance that helps blood vessels relax and widen. It is popularly used for bl...

L-Arginine monograph & interactions

L-Citrulline

Interacts with
178 drugs
1600 mg per serving

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. I...

L-Citrulline monograph & interactions

L-Glycine

Interacts with
1 drug
1200 mg per serving

Glycine is a non-essential amino acid your body makes on its own and that also appears in protein-rich foods. It is most studied for improving sleep q...

L-Glycine monograph & interactions

L-Ornithine Hydrochloride

No known
interactions
1020 mg per serving

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 fo...

L-Ornithine Hydrochloride monograph & interactions

Creatine Monohydrate

No known
interactions
3000 mg per serving

Creatine is one of the most studied sports supplements, with solid evidence that it can boost strength and performance during short, high-intensity ac...

Creatine Monohydrate monograph & interactions

Niacin

Interacts with
727 drugs
200 mg per serving Form: Nicotinamide, Nicotinic Acid

Niacin (vitamin B3) is an essential nutrient your body needs for energy and metabolism, and deficiency is uncommon in most developed countries. Prescr...

Niacin monograph & interactions

MyHMB

3000 mg per serving Form: Calcium Hydroxymethylbutrate Monohydrate

Other (inactive) ingredients: Dicalcium Phosphate, Microcrystalline Cellulose, Stearic Acid, Croscarmellose Sodium, Pharmaceutical Glaze, Magnesium Stearate, Silicon Dioxide, Hydroxypropyl Methylcellulose, Gum Acacia, Hydroxypropyl Cellulose, Wax, Micronized, Talc. These complete the product’s ingredient list but are not active constituents.

Interaction report

Muscle Synergy by Beverly International Drug Interactions

Want to check YOUR meds against Muscle Synergy?

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
747Drugs
747 Moderate

Ingredients driving the most interactions

Niacin 727
L-Arginine 403
L-Citrulline 178
L-Glycine 1

Individual Drug Interactions

The ingredients in Muscle Synergy interact with 747 drugs. Click any drug to see the details.

4 of the 7 ingredients in Muscle Synergy interact with drugs. Each result below shows which ingredient is responsible. Niacin L-Arginine L-Citrulline L-Glycine

Each ingredient & the kinds of drugs it affects

For each ingredient in Muscle Synergy 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.

Niacin15 drug types · 727 drugs

Alcohol (Ethanol)

Concomitant use of alcohol and niacin might increase the risk of flushing and hepatotoxicity.
Alcohol can exacerbate the flushing and pruritus associated with niacin. Large doses of niacin might also exacerbate liver dysfunction associated with chronic alcohol use. A case report describes delirium and lactic acidosis in a patient taking niacin 3 grams daily who ingested 1 liter of wine. Advise patients to avoid large amounts of alcohol while taking niacin.

Likelihood Probable Evidence D
Allopurinol (Zyloprim)

Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as allopurinol.
Large doses of niacin can reduce urinary excretion of uric acid, potentially resulting in hyperuricemia. Doses of uricosurics such as allopurinol might need to be increased to maintain control of gout in patients who start taking niacin. People who have frequent attacks of gout despite uricosuric therapy should avoid niacin.

Likelihood Probable Evidence C
Anticoagulant/Antiplatelet Drugs

Theoretically, niacin may have additive effects when used with anticoagulant or antiplatelet drugs.
Several cases of clotting factor synthesis deficiency and coagulopathy have been reported in patients taking sustained-release niacin. Also, thrombocytopenia has been reported in patients treated with niacin or niacin plus lovastatin.

Likelihood Possible Evidence D
Antidiabetes Drugs

Niacin can increase blood glucose levels and may diminish the effects of antidiabetes drugs.
Niacin impairs glucose tolerance in a dose-dependent manner, probably by causing or aggravating insulin resistance and increasing hepatic production of glucose. In diabetes patients, niacin 4.5 grams daily for 5 weeks can increase plasma glucose by an average of 16% and glycated hemoglobin (HbA1c) by 21%. However, lower doses of 1.5 grams daily or less appear to have minimal effects on blood glucose. In some patients, glucose levels increase when niacin is started, but then return to baseline when a stable dose is reached. Up to 35% of patients with diabetes may need adjustments in hypoglycemic therapy when niacin is added.

Likelihood Probable Evidence B
Antihypertensive Drugs

Theoretically, niacin may increase the risk of hypotension when used with antihypertensive drugs.
The vasodilating effects of niacin can cause hypotension. Furthermore, some clinical evidence suggests that a one-hour infusion of niacin can reduce systolic, diastolic, and mean blood pressure in hypertensive patients. This effect is not observed in normotensive patients.

Likelihood Possible Evidence B
Bile Acid Sequestrants

Bile acid sequestrants can bind niacin and decrease absorption. Separate administration by 4-6 hours to avoid an interaction.
In vitro studies show that colestipol (Colestid) binds about 98% of available niacin and cholestyramine (Questran) binds 10% to 30%.

Likelihood Possible Evidence D
Gemfibrozil (Lopid)

Theoretically, concomitant use of niacin and gemfibrozil might increase the risk of myopathy in some patients.
A case of myopathy from concomitant use of niacin and gemfibrozil has been reported. Niacin alone has also been associated with cases of myopathy. Using gemfibrozil with niacin might further increase the risk of developing myopathy.

Likelihood Possible Evidence D
Hepatotoxic Drugs

Theoretically, concomitant use of niacin and hepatotoxic drugs might increase the risk of hepatotoxicity.
Niacin has been associated with cases of liver toxicity, especially when used in pharmacologic doses. Sustained-release niacin preparations appear to be associated with a higher risk of hepatotoxicity than immediate-release niacin.

Likelihood Possible Evidence D
Hmg-Coa Reductase Inhibitors ("Statins")

Theoretically, concomitant use of niacin and statins might increase the risk of myopathy and rhabdomyolysis in some patients.
Some case reports have raised concerns that niacin might increase the risk of myopathy and rhabdomyolysis when combined with statins. However, a significantly increased risk of myopathy has not been demonstrated in clinical trials, including those using an FDA-approved combination of lovastatin and niacin (Advicor).

Likelihood Possible Evidence D
Probenecid (Benemid)

Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as probenecid.
Large doses of niacin reduce urinary excretion of uric acid, potentially causing hyperuricemia. Doses of uricosurics such as probenecid might need to be increased to maintain control of gout in patients who start taking niacin. People who have frequent attacks of gout despite uricosuric therapy should avoid niacin.

Likelihood Probable Evidence C
Sulfinpyrazone (Anturane)

Theoretically, niacin might antagonize the therapeutic effects of uricosurics such as sulfinpyrazone.
Large doses of niacin reduce urinary excretion of uric acid, potentially causing hyperuricemia. Doses of uricosurics such as sulfinpyrazone might need to be increased to maintain control of gout in patients who start taking niacin. People who have frequent attacks of gout despite uricosuric therapy should avoid niacin.

Likelihood Probable Evidence C
Thyroid Hormone

Theoretically, niacin might antagonize the therapeutic effects of thyroid hormones.
Clinical research and case reports suggests that taking niacin can reduce serum levels of thyroxine-binding globulin by up to 25% and moderately reduce levels of thyroxine (T4). Patients taking thyroid hormone for hypothyroidism might need dose adjustments when using niacin.

Likelihood Probable Evidence D
Transdermal Nicotine (Nicoderm)

Theoretically, concomitant use of niacin and transdermal nicotine might increase the risk of flushing and dizziness.
Niacin and nicotine can both cause flushing and dizziness.

Likelihood Possible Evidence D
Warfarin (Coumadin)

There is limited evidence that niacin may increase the anticoagulant effects of warfarin.
In a case report, a patient on warfarin developed an elevated international normalized ratio (INR) of 3.9 after taking niacin for two weeks. The patient's INR was previously stable, ranging between 2 and 3 in recent months, and no other medication changes were identified. The elevated INR returned to therapeutic range within 4 days following the discontinuation of niacin.

Likelihood Possible Evidence D
Aspirin

Large doses of aspirin might alter the clearance of niacin.
Aspirin is often used with niacin to reduce niacin-induced flushing. Doses of 80-975 mg aspirin have been used, but 325 mg appears to be optimal. Aspirin also seems to reduce the clearance of niacin by competing for glycine conjugation. Taking aspirin 1 gram seems to reduce niacin clearance by 45%. This is probably a dose-related effect and not clinically significant with the more common aspirin dose of 325 mg.

Likelihood Likely Evidence B
Niacin full monograph & interactions

L-Arginine9 drug types · 403 drugs

Ace Inhibitors (Aceis)

Theoretically, concomitant use of L-arginine and ACE inhibitors may increase the risk for hypotension and hyperkalemia.
Combining L-arginine with some antihypertensive drugs, especially ACE inhibitors, seems to have additive vasodilating and blood pressure-lowering effects. Furthermore, ACE inhibitors can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concomitant use of ACE inhibitors with L-arginine may increases the risk of hyperkalemia.

Likelihood Probable Evidence D
Angiotensin Receptor Blockers (Arbs)

Theoretically, concomitant use of L-arginine and ARBs may increase the risk of hypotension and hyperkalemia.
L-arginine increases nitric oxide, which causes vasodilation. Combining L-arginine with ARBs seems to increase L-arginine-induced vasodilation. Furthermore, ARBs can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients. Theoretically, concomitant use of ARBs with L-arginine may increases the risk of hyperkalemia.

Likelihood Probable Evidence D
Anticoagulant/Antiplatelet Drugs

Theoretically, concomitant use of L-arginine with anticoagulant and antiplatelet drugs might have additive effects and increase the risk of bleeding.
Preliminary research suggests that L-arginine infusions reduce platelet aggregation in humans. The clinical significance of this effect is unclear.

Likelihood Possible Evidence D
Antidiabetes Drugs

Theoretically, concomitant use of L-arginine might have additive effects with antidiabetes drugs.
Preliminary clinical research shows that L-arginine decreases blood glucose levels in patients with type 2 diabetes.

Likelihood Possible Evidence D
Antihypertensive Drugs

Theoretically, concomitant use of L-arginine and antihypertensive drugs may increase the risk of hypotension.
L-arginine increases nitric oxide, which causes vasodilation. Clinical evidence shows that L-arginine can reduce blood pressure in some individuals with hypertension. Furthermore, combining L-arginine with some antihypertensive drugs seems to have additive vasodilating and blood pressure-lowering effects.

Likelihood Probable Evidence D
Isoproterenol (Isuprel)

Theoretically, concurrent use of isoproterenol and L-arginine might result in additive effects and hypotension.
Preliminary clinical evidence suggests that L-arginine enhances isoproterenol-induced vasodilation in patients with essential hypertension or a family history of essential hypertension.

Likelihood Probable Evidence D
Potassium-Sparing Diuretics

Theoretically concomitant use of potassium-sparing diuretics with L-arginine may increases the risk of hyperkalemia.
Potassium-sparing diuretics can increase potassium levels. Use of L-arginine has been associated with hyperkalemia in some patients.

Likelihood Possible Evidence D
Sildenafil (Viagra)

Theoretically, concurrent use of sildenafil and L-arginine might increase the risk for hypotension.
In vivo, concurrent use of L-arginine and sildenafil has resulted in increased vasodilation. Theoretically, concurrent use 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
Testosterone

Theoretically, concomitant use of L-arginine and testosterone might have additive effects.
In clinical research, L-arginine increases the level of testosterone in male patients with erectile dysfunction. The clinical significance of this finding is unclear.

Likelihood Possible Evidence D
L-Arginine 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-Glycine1 drug type · 1 drug

Clozapine (Clozaril)

Theoretically, glycine might decrease the effectiveness of clozapine.
One small clinical study in patients with schizophrenia shows that adding glycine to clozapine therapy worsens symptoms of schizophrenia when compared with clozapine alone. The mechanism of this interaction is unclear.

Likelihood Probable Evidence B
L-Glycine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for Muscle Synergy, from the product label.

Beverly International

See all Beverly International products
Name
Beverly International Nutrition, Inc
City
Cold Spring
State
KY
ZipCode
41076
Phone Number
(800) 781-3475
Web Address
www.BeverlyInternational.com
Pharmacist Counseling Corner

Muscle Synergy by Beverly International: Common Questions

Does Muscle Synergy by Beverly International interact with any medications?
Yes. Based on its ingredients, Muscle Synergy has a known interaction with 747 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Muscle Synergy contains 7 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.
Will this help me build muscle?
Some of the ingredients — L-citrulline, L-ornithine, and creatine — are rated possibly effective for athletic performance and muscle strength. L-arginine and niacin don't have established evidence in our data for muscle building specifically. Results depend on the ingredient doses, your training, and individual variation.
Can I take this if I'm pregnant or breastfeeding?
Safety data are limited for most ingredients here. L-arginine is rated possibly safe in pregnancy, and niacin at normal prenatal-vitamin doses is likely safe. For L-citrulline, L-ornithine, creatine, and myHMB, there isn't enough data — avoid them unless your doctor says otherwise. For breastfeeding, avoid L-citrulline, L-ornithine, and creatine supplements. Talk to your doctor or pharmacist about your individual situation.
What side effects should I expect?
Common side effects from L-arginine include bloating, nausea, diarrhea, and headache. L-citrulline may cause heartburn or gastrointestinal discomfort. Creatine often causes water retention and can lead to dehydration or muscle cramps. Niacin frequently causes flushing and stomach upset. Most other side effects are mild and resolve if you stop the product.
Is this safe if I have kidney problems?
Creatine monohydrate requires caution in people with kidney issues — the safety notes specifically flag this. Talk with your doctor or pharmacist before using this product if you have any kidney condition.
What is myHMB?
MyHMB is one of the seven active ingredients in this product. We don't hold interaction data for it, so we can't comment on its safety profile relative to medications, but we recommend asking your pharmacist if you take any prescription drugs.
Why do I need to check my medications before taking this?
L-arginine and L-citrulline both lower blood pressure and can interact with blood pressure drugs, blood thinners, heart medications, and diabetes drugs — sometimes with serious effects like low blood pressure or bleeding. Niacin can interfere with liver function and interact with statins and gout meds. It's essential to run your exact prescriptions through the checker on this page.

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.

Muscle Synergy label
Go deeper

The Full Monographs Behind Muscle Synergy’s Ingredients

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

Herb & supplement monograph

L-arginine

Interacts with 403 drugs

L-arginine is an amino acid that the body uses to make nitric oxide, a substance that helps blood vessels relax and widen. It is popularly used for blood pressure, erectile dysfunction, and...

Read the full L-arginine 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

Glycine

Interacts with 1 drug

Glycine is a non-essential amino acid your body makes on its own and that also appears in protein-rich foods. It is most studied for improving sleep quality, where early research is promisin...

Read the full Glycine 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

Creatine

Creatine is one of the most studied sports supplements, with solid evidence that it can boost strength and performance during short, high-intensity activities like weightlifting and sprintin...

Read the full Creatine monograph → Herb & supplement monograph

Niacin

Interacts with 727 drugs

Niacin (vitamin B3) is an essential nutrient your body needs for energy and metabolism, and deficiency is uncommon in most developed countries. Prescription-strength niacin has been used to...

Read the full Niacin monograph →
Sources

Sources & How We Checked

Muscle Synergy'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 232 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-arginine 66 references
  1. Sapienza MA, Kharitonov SA, Horvath I, et al. Effect of inhaled L-arginine on exhaled nitric oxide in normal and asthmatic subjects. Thorax 1998;53:172-5.
  2. Clarkson P, Adams MR, Powe AJ, et al. Oral L-arginine improves endothelium-dependent dilation in hypercholesterolemic young adults. J Clin Invest 1996;97:1989-94. PubMed
  3. Tenenbaum A, Fisman EZ, Motro M. L-arginine: Rediscovery in progress. Cardiology 1998;90:153-9.
  4. Brittenden J, Park KGM, Heys SD, et al. L-Arginine stimulates host defenses in patients with breast cancer. Surgery 1994;115:205-12.
  5. Korting GE, Smith SD, Wheeler MA, et al. A randomized double-blind trial of oral L-arginine for treatment of interstitial cystitis. J Urol 1999;161:558-65. DOI
  6. Rector TS, Bank AJ, Mullen KA, et al. Randomized, double-blind, placebo-controlled study of supplemental oral L-arginine in patients with heart failure. Circulation 1996;93:2135-41.
  7. Siani A, Pagano E, Iacone R, et al. Blood pressure and metabolic changes during dietary L-arginine supplementation in humans. Am J Hypertens 2000;13:547-51. PubMed
  8. Cheng JW, Balwin SN. L-arginine in the management of cardiovascular diseases. Ann Pharmacother 2001;35:755-64. PubMed
  9. Wallace AW, Tom WL. Interaction of L-arginine and phosphodiesterase inhibitors in vasodilation of the porcine internal mammary artery. Anesth Analg 2000;90:840-6. DOI
  10. Huynh NT, Tayek JA. Oral arginine reduces systemic blood pressure in type 2 diabetes: its potential role in nitric oxide generation. J Am Coll Nutr 2002;21:422-7.. PubMed
  11. Staff AC, Berge L, Haugen G, et al. Dietary supplementation with L-arginine or placebo in women with pre-eclampsia. Acta Obstet Gynecol Scand 2004;83:103-7.
  12. Resnick DJ, Softness B, Murphy AR, et al. Case report of an anaphylactoid reaction to arginine. Ann Allergy Asthma Immunol 2002;88:67-8. PubMed
  13. Anon. Arginine hydrochloride injection (marketed as R-Gene 10). FDA Drug Safety Newsletter 2009;2(2):16-18. Available at: www.fda.gov/Drugs/DrugSafety/DrugSafetyNewsletter/default.htm.
  14. Higashi Y, Oshima T, Sasaki S, et. al. Angiotensin-converting enzyme inhibition, but not calcium antagonism, improves a response of the renal vasculature to L-arginine in patients with essential hypertension. Hypertension. 1998 Jul;32(1):16-24.
  15. Facchinetti, F., Longo, M., Piccinini, F., Neri, I., and Volpe, A. L-arginine infusion reduces blood pressure in preeclamptic women through nitric oxide release. J Soc Gynecol.Investig. 1999;6(4):202-207. DOI
  16. de Gouw, H. W., Verbruggen, M. B., Twiss, I. M., and Sterk, P. J. Effect of oral L-arginine on airway hyperresponsiveness to histamine in asthma. Thorax 1999;54(11):1033-1035. PubMed
  17. Komers, R., Komersova, K., Kazdova, L., Ruzickova, J., and Pelikanova, T. Effect of ACE inhibition and angiotensin AT1 receptor blockade on renal and blood pressure response to L-arginine in humans. J Hypertens. 2000;18(1):51-59. PubMed
  18. Cartledge, J. J., Davies, A. M., and Eardley, I. A randomized double-blind placebo-controlled crossover trial of the efficacy of L-arginine in the treatment of interstitial cystitis. BJU.Int. 2000;85(4):421-426.
  19. Sozykin, A. V., Noeva, E. A., Balakhonova, T. V., Pogorelova, O. A., and Men'shikov, M. I. [Effect of L-arginine on platelet aggregation, endothelial function adn exercise tolerance in patients with stable angina pectoris]. Ter.Arkh. 2000;72(8):24-27.
  20. Nagaya, N., Uematsu, M., Oya, H., Sato, N., Sakamaki, F., Kyotani, S., Ueno, K., Nakanishi, N., Yamagishi, M., and Miyatake, K. Short-term oral administration of L-arginine improves hemodynamics and exercise capacity in patients with precapillary pulmona
  21. Stokes, G. S., Barin, E. S., Gilfillan, K. L., and Kaesemeyer, W. H. Interactions of L-arginine, isosorbide mononitrate, and angiotensin II inhibitors on arterial pulse wave. Am J Hypertens. 2003;16(9 Pt 1):719-724.
  22. Park, K. G., Heys, S. D., Blessing, K., Kelly, P., McNurlan, M. A., Eremin, O., and Garlick, P. J. Stimulation of human breast cancers by dietary L-arginine. Clin.Sci.(Lond) 1992;82(4):413-417.
  23. Palloshi, A., Fragasso, G., Piatti, P., Monti, L. D., Setola, E., Valsecchi, G., Galluccio, E., Chierchia, S. L., and Margonato, A. Effect of oral L-arginine on blood pressure and symptoms and endothelial function in patients with systemic hypertension,
  24. Schlaich, M. P., Ahlers, B. A., Parnell, M. M., and Kaye, D. M. beta-Adrenoceptor-mediated, nitric-oxide-dependent vasodilatation is abnormal in early hypertension: restoration by L-arginine. J Hypertens. 2004;22(10):1917-1925. PubMed
  25. Neri, I., Blasi, I., and Facchinetti, F. Effects of acute L-arginine infusion on non-stress test in hypertensive pregnant women. J Matern.Fetal Neonatal Med. 2004;16(1):23-26. PubMed
  26. Rytlewski, K., Olszanecki, R., Korbut, R., and Zdebski, Z. Effects of prolonged oral supplementation with l-arginine on blood pressure and nitric oxide synthesis in preeclampsia. Eur.J Clin.Invest 2005;35(1):32-37.
  27. Mansoor, J. K., Morrissey, B. M., Walby, W. F., Yoneda, K. Y., Juarez, M., Kajekar, R., Severinghaus, J. W., Eldridge, M. W., and Schelegle, E. S. L-arginine supplementation enhances exhaled NO, breath condensate VEGF, and headache at 4,342 m. High Alt.M
  28. Neri, I., Jasonni, V. M., Gori, G. F., Blasi, I., and Facchinetti, F. Effect of L-arginine on blood pressure in pregnancy-induced hypertension: a randomized placebo-controlled trial. J Matern.Fetal Neonatal Med. 2006;19(5):277-281.
  29. Lucotti, P., Setola, E., Monti, L. D., Galluccio, E., Costa, S., Sandoli, E. P., Fermo, I., Rabaiotti, G., Gatti, R., and Piatti, P. Beneficial effects of a long-term oral L-arginine treatment added to a hypocaloric diet and exercise training program in
  30. Savoye, G., Jemaa, Y., Mosni, G., Savoye-Collet, C., Morcamp, P., Dechelotte, P., Bouin, M., Denis, P., and Ducrotte, P. Effects of intragastric L-arginine administration on proximal stomach tone under basal conditions and after an intragastric diet. Dig PubMed
  31. Facchinetti, F., Saade, G. R., Neri, I., Pizzi, C., Longo, M., and Volpe, A. L-arginine supplementation in patients with gestational hypertension: a pilot study. Hypertens.Pregnancy. 2007;26(1):121-130. PubMed
  32. Jovanovic, A., Gerrard, J., and Taylor, R. The second-meal phenomenon in type 2 diabetes. Diabetes Care 2009;32(7):1199-1201. PubMed
  33. Fontanive P, Saponati G, Iurato A, et al. Effects of L-arginine on the Minnesota Living with Heart Failure Questionnaire quality-of-life score in patients with chronic systolic heart failure. Med.Sci.Monit. 2009;15:CR606-11.
  34. Doutreleau, S., Rouyer, O., Di, Marco P., Lonsdorfer, E., Richard, R., Piquard, F., and Geny, B. L-arginine supplementation improves exercise capacity after a heart transplant. Am J Clin.Nutr. 2010;91(5):1261-1267. PubMed
  35. Ast, J., Jablecka, A., Bogdanski, P., Smolarek, I., Krauss, H., and Chmara, E. Evaluation of the antihypertensive effect of L-arginine supplementation in patients with mild hypertension assessed with ambulatory blood pressure monitoring. Med.Sci.Monit. 2
  36. Saleh, A. I., Abdel Maksoud, S. M., El-Maraghy, S. A., and Gad, M. Z. Protective effect of L-arginine in experimentally induced myocardial ischemia: comparison with aspirin. J Cardiovasc.Pharmacol.Ther 2011;16(1):53-62. PubMed
  37. Dong, J. Y., Qin, L. Q., Zhang, Z., Zhao, Y., Wang, J., Arigoni, F., and Zhang, W. Effect of oral L-arginine supplementation on blood pressure: a meta-analysis of randomized, double-blind, placebo-controlled trials. Am.Heart J 2011;162(6):959-965. PubMed
  38. Hertz, P. and Richardson, J. A. Arginine-induced hyperkalemia in renal failure patients. Arch.Intern.Med. 1972;130(5):778-780. DOI
  39. Bushinsky, D. A. and Gennari, F. J. Life-threatening hyperkalemia induced by arginine. Ann.Intern.Med. 1978;89(5 Pt 1):632-634. PubMed
  40. Adams, M. R., Forsyth, C. J., Jessup, W., Robinson, J., and Celermajer, D. S. Oral L-arginine inhibits platelet aggregation but does not enhance endothelium-dependent dilation in healthy young men. J Am Coll.Cardiol 1995;26(4):1054-1061. PubMed
  41. Dell'Omo, G., Catapano, G., Ebel, M., Gazzano, A., Ducci, M., Del, Chicca M., Clerico, A., and Pedrinelli, R. [Pressor, renal and endocrine effects of systemic infusion of L-arginine in hypertensive patients]. Ann.Ital Med.Int. 1995;10(2):107-112.
  42. Higashi, Y., Oshima, T., Ozono, R., Watanabe, M., Matsuura, H., and Kajiyama, G. Effects of L-arginine infusion on renal hemodynamics in patients with mild essential hypertension. Hypertension 1995;25(4 Pt 2):898-902.
  43. Bode-Boger, S. M., Boger, R. H., Creutzig, A., Tsikas, D., Gutzki, F. M., Alexander, K., and Frolich, J. C. L-arginine infusion decreases peripheral arterial resistance and inhibits platelet aggregation in healthy subjects. Clin.Sci.(Lond) 1994;87(3):303
  44. Marfella, R., Acampora, R., Verrazzo, G., Ziccardi, P., De, Rosa N., Giunta, R., and Giugliano, D. Metformin improves hemodynamic and rheological responses to L-arginine in NIDDM patients. Diabetes Care 1996;19(9):934-939. PubMed
  45. Giugliano, D., Marfella, R., Verrazzo, G., Acampora, R., Coppola, L., Cozzolino, D., and D'Onofrio, F. The vascular effects of L-Arginine in humans. The role of endogenous insulin. J Clin.Invest 2-1-1997;99(3):433-438. PubMed
  46. Khan, F., Litchfield, S. J., McLaren, M., Veale, D. J., Littleford, R. C., and Belch, J. J. Oral L-arginine supplementation and cutaneous vascular responses in patients with primary Raynaud's phenomenon. Arthritis Rheum. 1997;40(2):352-357.
  47. Wolf, A., Zalpour, C., Theilmeier, G., Wang, B. Y., Ma, A., Anderson, B., Tsao, P. S., and Cooke, J. P. Dietary L-arginine supplementation normalizes platelet aggregation in hypercholesterolemic humans. J Am Coll.Cardiol 3-1-1997;29(3):479-485. PubMed
  48. Schellong, S. M., Boger, R. H., Burchert, W., Bode-Boger, S. M., Galland, A., Frolich, J. C., Hundeshagen, H., and Alexander, K. Dose-related effect of intravenous L-arginine on muscular blood flow of the calf in patients with peripheral vascular disease
  49. Marietta, M., Facchinetti, F., Neri, I., Piccinini, F., Volpe, A., and Torelli, G. L-arginine infusion decreases platelet aggregation through an intraplatelet nitric oxide release. Thromb.Res 10-15-1997;88(2):229-235. PubMed
  50. Bauer JD, Isenring E, Waterhouse M. The effectiveness of a specialised oral nutrition supplement on outcomes in patients with chronic wounds: a pragmatic randomised study. J Hum Nutr Diet. 2013 Oct;26(5):452-8. PubMed
  51. Vadillo-Ortega F, Perichart-Perera O, Espino S, et al. Effect of supplementation during pregnancy with L-arginine and antioxidant vitamins in medical food on pre-eclampsia in high risk population: randomised controlled trial. BMJ. 2011 May 19;342:d2901. PubMed
  52. Camarena Pulido EE, García Benavides L, Panduro Barón JG, et al. Efficacy of L-arginine for preventing preeclampsia in high-risk pregnancies: A double-blind, randomized, clinical trial. Hypertens Pregnancy. 2016;35(2):217-25. PubMed
  53. Yokota T, Hamauchi S, Yoshida Y, et al. A phase II study of HMB/Arg/Gln against oral mucositis induced by chemoradiotherapy for patients with head and neck cancer. Support Care Cancer. 2018;26(9):3241-3248. PubMed
  54. Binet Q, Dufour I, Agneessens E, et al. The second case of a young man with L-arginine-induced acute pancreatitis. Clin J Gastroenterol. 2018;11(5):424-427. PubMed
  55. El Taieb M, Hegazy E, Ibrahim A. Daily oral l-arginine plus tadalafil in diabetic patients with erectile dysfunction: A double-blinded, randomized, controlled clinical trial. J Sex Med. 2019;16(9):1390-1397.
  56. Gallo L, Pecoraro S, Sarnacchiaro P, Silvani M, Antonini G. The daily therapy with L-arginine 2,500 mg and tadalafil 5 mg in combination and in monotherapy for the treatment of erectile dysfunction: A prospective, randomized multicentre study. Sex Med. 20 PubMed
  57. de la Parra PR, González-Cruz MÁ, Ferreiro-Marin A, Casaubón-Garcín PR. L-arginine-induced esophagitis, report of six cases. Bol Med Hosp Infant Mex. 2020;77(1):38-41. PubMed
  58. El-Wakeel LM, Fouad FA, Saleem MD, Saber-Khalaf M. Efficacy and tolerability of sildenafil/l-arginine combination relative to sildenafil alone in patients with organic erectile dysfunction. Andrology. 2020;8(1):143-147.
  59. Abu El-Hamd M, Hegazy EM. Comparison of the clinical efficacy of daily use of L-arginine, tadalafil and combined L-arginine with tadalafil in the treatment of elderly patients with erectile dysfunction. Andrologia. 2020;52(7):e13640. PubMed
  60. Liao SY, Showalter MR, Linderholm AL, et al. l-Arginine supplementation in severe asthma. JCI Insight. 2020;5(13):e137777. PubMed
  61. Yousefi Rad E, Nazarian B, Saboori S, Falahi E, Hekmatdoost A. Effects of l-arginine supplementation on glycemic profile: Evidence from a systematic review and meta-analysis of clinical trials. J Integr Med. 2020;18(4):284-291. PubMed
  62. 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
  63. Goto E. Effects of prenatal oral L-arginine on birth outcomes: a meta-analysis. Sci Rep 2021;11(1):22748. PubMed
  64. Monari F, Menichini D, Pignatti L, Basile L, Facchinetti F, Neri I. Effect of L-arginine supplementation in pregnant women with chronic hypertension and previous placenta vascular disorders receiving Aspirin prophylaxis: a randomized control trial. Minerv PubMed
  65. Li H, Liu Q, Zou Z, et al. L-arginine supplementation to mitigate cardiovascular effects of walking outside in the context of traffic-related air pollution in participants with elevated blood pressure: A randomized, double-blind, placebo-controlled trial. PubMed
  66. Shiraseb F, Asbaghi O, Bagheri R, Wong A, Figueroa A, Mirzaei K. The Effect of L-arginine Supplementation On Blood Pressure in Adults: A Systematic Review and Dose-response Meta-analysis of Randomized Clinical Trials. Adv Nutr 2021. PubMed

See these in context on the L-arginine 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 →

Glycine 5 references
  1. Heresco-Levy U, Javitt DC, Ermilov M, et al. Efficacy of high-dose glycine in the treatment of enduring negative symptoms of schizophrenia. Arch Gen Psychiatry 1999;56:29-36.. PubMed
  2. Potkin SG, Jin Y, Bunney BG, Costa J, Gulasekaram B. Effect of clozapine and adjunctive high-dose glycine in treatment-resistant schizophrenia. Am J Psychiatry 1999;156:145-7.. PubMed
  3. Gusev EI, Skvortsova VI, Dambinova SA, et al. Neuroprotective effects of glycine for therapy of acute ischaemic stroke. Cerebrovasc Dis 2000;10:49-60. PubMed
  4. Inagawa K, Kawai N, Ono K, Sukegawa E, Tsubuku S, Takahashi M. Assessment of acute adverse effects of glycine ingestion at a high dose in human volunteers. Seikatsu Eisei. 2006; 50:27-32.
  5. Woods SW, Walsh BC, Hawkins KA, Miller TJ, Saksa JR, D'Souza DC, Pearlson GD, Javitt DC, McGlashan TH, Krystal JH. Glycine treatment of the risk syndrome for psychosis: report of two pilot studies. Eur Neuropsychopharmacol. 2013 Aug;23(8):931-40. PubMed

See these in context on the Glycine 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 →

Creatine 86 references
  1. Koshy KM, Griswold E, Schneeberger EE. Interstitial nephritis in a patient taking creatine. N Engl J Med 1999;340:814-5. PubMed
  2. 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.
  3. Greenhaff P. Renal dysfunction accompanying oral creatine supplements. Lancet 1998;352:233-4. PubMed
  4. Vandenberghe K, Goris M, Van Hecke P, et al. Long-term creatine intake is beneficial to muscle performance during resistance training (abstract). J Appl Physiol 1997;83:2055-63. PubMed
  5. Hultman E, Soderlund K, Timmons JA, et al. Muscle creatine loading in men. J Appl Physiol 1996;81:232-7. PubMed
  6. Pritchard NR, Kalra PA. Renal dysfunction accompanying oral creatine supplements. Lancet 1998;351:1252-3. PubMed
  7. Poortmans JR, Auquier H, Renaut V, et al. Effect of short-term creatine supplementation on renal responses in men (abstract). Eur J Appl Physiol Occup Physiol 1997;76:566-7. PubMed
  8. Poortmans JR, Francaux M. Long-term oral creatine supplementation does not impair renal function in healthy athletes. Med Sci Sports Exerc 1999;31:1108-10. PubMed
  9. Mihic S, MacDonald JR, McKenzie S, Tarnopolsky MA. Acute creatine loading increases fat-free mass, but does not affect blood pressure, plasma creatinine, or CK activity in men and women. Med Sci Sports Exerc 2000;32:291-6. PubMed
  10. Rawson ES, Wehnert ML, Clarkson PM. Effects of 30 days of creatine ingestion in older men. Eur J Appl Physiol Occup Physiol 1999;80:139-44. PubMed
  11. Earnest CP, Almada AL, Mitchell TL. High-performance capillary electrophoresis-pure creatine monohydrate reduces blood lipids in men and women. Clin Sci (Colch) 1996;91:113-8. PubMed
  12. Juhn MS. Oral creatine supplementation. Separating fact from hype. Phys Sportsmed 1999;27:47-50,53-54,56,61,89. PubMed
  13. Juhn MS, O'Kane JW, Vinci DM. Oral creatine supplementation in male collegiate athletes: a survey of dosing habits and side effects. J Am Diet Assoc 1999;99:593-5.
  14. Green AL, Hultman E, Macdonald IA, et al. Carbohydrate ingestion augments skeletal muscle creatine accumulation during creatine supplementation in humans. Am J Physiol 1996;271:E821-6. PubMed
  15. Balsom PD, Soderlund K, Sjodin B, Ekblom B. Skeletal muscle metabolism during short duration high-intensity exercise: influence of creatine supplementation. Acta Physiol Scand 1995;154:303-10. PubMed
  16. Snow RJ, McKenna MJ, Selig SE, et al. Effect of creatine supplementation on sprint exercise performance and muscle metabolism. (abstract) J Appl Physiol 1998;84:1667-73. PubMed
  17. McNaughton LR, Dalton B, Tarr J. The effects of creatine supplementation on high-intensity exercise performance in elite performers. (abstract) Eur J Appl Physiol Occup Physiol 1998;78:236-40. PubMed
  18. Groeneveld GJ, Veldink JH, van der Tweel I, et al. A randomized sequential trial of creatine in amyotrophic lateral sclerosis. Ann Neurol 2003;53:437-45. . PubMed
  19. Robinson SJ. Acute quadriceps compartment syndrome and rhabdomyolysis in a weight lifter using high-dose creatine supplementation. J Am Board Fam Pract 2000;13:134-7. PubMed
  20. Kammer RT. Lone atrial fibrillation associated with creatine monohydrate supplementation. Pharmacotherapy 2005;25:762-4. PubMed
  21. Gualano B, Ugrinowitsch C, Novaes RB, et al. Effects of creatine supplementation on renal function: a randomized, double-blind, placebo-controlled clinical trial. Eur J Appl Physiol 2008;103:33-40. PubMed
  22. Pfeffer, G., Majamaa, K., Turnbull, D. M., Thorburn, D., and Chinnery, P. F. Treatment for mitochondrial disorders. Cochrane Database.Syst.Rev. 2012;4:CD004426. PubMed
  23. Boos, C. J., White, S. H., Bland, S. A., and McAllister, P. D. Dietary supplements and military operations: caution is advised. J R.Army Med Corps 2010;156(1):41-43. PubMed
  24. Kreider, R. B. Dietary supplements and the promotion of muscle growth with resistance exercise. Sports Med 1999;27(2):97-110. PubMed
  25. Juhn, M. S., O'Kane, J. W., and Vinci, D. M. Oral creatine supplementation in male collegiate athletes: a survey of dosing habits and side effects. J Am.Diet.Assoc 1999;99(5):593-595.
  26. Volek, J. S., Duncan, N. D., Mazzetti, S. A., Putukian, M., Gomez, A. L., and Kraemer, W. J. No effect of heavy resistance training and creatine supplementation on blood lipids. Int J Sport Nutr.Exerc.Metab 2000;10(2):144-156. PubMed
  27. Robinson, T. M., Sewell, D. A., Casey, A., Steenge, G., and Greenhaff, P. L. Dietary creatine supplementation does not affect some haematological indices, or indices of muscle damage and hepatic and renal function. Br.J Sports Med 2000;34(4):284-288. PubMed
  28. Tarnopolsky, M. A. Potential benefits of creatine monohydrate supplementation in the elderly. Curr.Opin.Clin Nutr.Metab Care 2000;3(6):497-502. PubMed
  29. Tarnopolsky, M. A. and MacLennan, D. P. Creatine monohydrate supplementation enhances high-intensity exercise performance in males and females. Int J Sport Nutr.Exerc.Metab 2000;10(4):452-463. PubMed
  30. Arciero, P. J., Hannibal, N. S., III, Nindl, B. C., Gentile, C. L., Hamed, J., and Vukovich, M. D. Comparison of creatine ingestion and resistance training on energy expenditure and limb blood flow. Metabolism 2001;50(12):1429-1434. PubMed
  31. Chrusch, M. J., Chilibeck, P. D., Chad, K. E., Davison, K. S., and Burke, D. G. Creatine supplementation combined with resistance training in older men. Med Sci.Sports Exerc. 2001;33(12):2111-2117. PubMed
  32. Cox, G., Mujika, I., Tumilty, D., and Burke, L. Acute creatine supplementation and performance during a field test simulating match play in elite female soccer players. Int J Sport Nutr.Exerc.Metab 2002;12(1):33-46. PubMed
  33. Kilduff, L. P., Vidakovic, P., Cooney, G., Twycross-Lewis, R., Amuna, P., Parker, M., Paul, L., and Pitsiladis, Y. P. Effects of creatine on isometric bench-press performance in resistance-trained humans. Med Sci.Sports Exerc. 2002;34(7):1176-1183. PubMed
  34. Brose, A., Parise, G., and Tarnopolsky, M. A. Creatine supplementation enhances isometric strength and body composition improvements following strength exercise training in older adults. J Gerontol A Biol.Sci.Med Sci. 2003;58(1):11-19. PubMed
  35. Volek, J. S., Ratamess, N. A., Rubin, M. R., Gomez, A. L., French, D. N., McGuigan, M. M., Scheett, T. P., Sharman, M. J., Hakkinen, K., and Kraemer, W. J. The effects of creatine supplementation on muscular performance and body composition responses to
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