Interactions on record — worth a quick check against your medications. Based on 2 of 7 ingredients. Check your meds →
Dietary supplement

Best Glutamine Unflavored Ingredients & Drug Interactions

by BPI Sports

Best Glutamine Unflavored label
See full label image
Powder 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 Best Glutamine Unflavored 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

Best Glutamine Unflavored is a dietary supplement by BPI Sports with 7 active ingredients. Its ingredients are commonly taken for common cold and immune support, antioxidant support, skin health and collagen formation.Based on those ingredients, 256 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Vitamin C, L-Glutamine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

Jump to a section

Check Your Meds Against Best Glutamine Unflavored by BPI Sports

Ask about any prescription or over-the-counter medication and we check it for interactions with Best Glutamine Unflavored by BPI Sports — and tell you which ingredient is responsible.

Pharmacist-reviewed data Checks every ingredient Answer in seconds
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HelloPharmacist Scorecard of Best Glutamine Unflavored by BPI Sports

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

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 7 active ingredients.
  • “Best Glutamine Blend (Proprietary)” is a proprietary blend — the label gives one combined amount (6.50 Gram(s)) without saying how much of each component you get.

This powder contains 7 ingredients total, but only some are active. The active amino acids are L-Glutamine, Glutamic Acid, N-Acetyl-L-Glutamine, L-Alanyl-L-Glutamine, and Glutamine Alpha-Ketoglutarate, along with plain Glutamine—most of them forms or related compounds of glutamine, an amino acid your body uses for muscle and gut health.

Vitamin C is also active. The rest are inactive ingredients (fillers and flavor enhancers like citric acid, malic acid, sucralose, and silica) that make the powder work and taste better.

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 recovery and lean muscle building.
  • We looked for evidence on: Athletic performance, Exercise-induced muscle damage, Critical illness (trauma), HIV/AIDS-related wasting, Malnutrition, Muscular dystrophy — and 3 related terms.
  • The strongest evidence on file: Glutamine is rated "Possibly Effective" for HIV/AIDS-related wasting (Natural Medicines).
  • Also on file: Glutamine is rated "Possibly Effective" for Critical illness (trauma).
  • Also on file: Glutamine is rated "Possibly Ineffective" for Athletic performance, Muscular dystrophy.

The glutamine forms in this product are effective for sickle cell disease. They're rated possibly effective for HIV/AIDS-related wasting, recovery after surgery, and critical illness from trauma.

Vitamin C is effective for preventing vitamin C deficiency and is possibly effective for chronic disease anemia, atrial fibrillation, cataracts, and respiratory infections triggered by heavy exercise. The evidence for the other ingredients—Glutamic Acid, N-Acetyl-L-Glutamine, and L-Alanyl-L-Glutamine—isn't established in the data we hold.

The evidence, ingredient by ingredient Vitamin C Glutamine

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 2 of the 2 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 2 of 2.
  • General safety write-ups exist for 2 of 2.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Glutamine is generally well tolerated in healthy adults. The most common side effects are belly discomfort (belching, bloating, constipation, diarrhea, gas, pain), nausea, vomiting, cough, headache, and musculoskeletal pain.

High doses (10–30 grams daily) in clinical trials have caused nausea and GI pain. In rare cases, dizziness and mania or hypomania have been reported.

People with kidney or liver disease should only use glutamine under medical supervision. Vitamin C at normal doses is well tolerated, but very high doses can cause abdominal cramps, heartburn, diarrhea, nausea, vomiting, and kidney stones (especially in people prone to them).

For pregnancy and lactation: the glutamine in this product is rated likely safe, but vitamin C carries a likely-safe rating in pregnancy for normal amounts and a possibly-unsafe rating for some pregnancy/lactation contexts—talk with your doctor about high-dose supplements during pregnancy or breastfeeding.

Side effects, ingredient by ingredient Vitamin C Glutamine

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?
  • 2 of the 2 matched ingredients can interact with medications — Glutamine, Vitamin C.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: anticoagulant / antiplatelet drugs; seizure medications; cancer treatments.
  • For scale: 256 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 before you take this if you're on anticonvulsant (seizure prevention) drugs—glutamine may theoretically work against them. Also double-check if you take estrogen-based birth control or hormone therapy, blood thinners like warfarin, levothyroxine (thyroid hormone), chemotherapy drugs, or antipsychotic or HIV medications.

While no interactions are documented for Glutamic Acid, N-Acetyl-L-Glutamine, and L-Alanyl-L-Glutamine, we hold no data on those ingredients, so mention them to your pharmacist too.

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. Moderate medication interactions have been identified, and safety information is well characterized.

This glutamine and vitamin C powder is aimed at muscle recovery and immune support, backed by some evidence for specific conditions like sickle cell disease. It's generally well tolerated in healthy people, but you'll want to check your medications first—especially seizure preventers, blood thinners, thyroid drugs, and chemotherapy.

If you have kidney or liver disease, or if you're pregnant or breastfeeding, talk with your pharmacist before starting.

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

Assessment coverage: 4 of 7 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Oct 21, 2017.

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 Best Glutamine Unflavored, straight from the product label.

Brand BPI Sports
Barcode (UPC) 811213022655
Net contents 14.1 Oz(s); 400 Gram(s)
Market status On market
Date entered into DSLD Oct 21, 2017
DSLD ID 79819
Product type Other Combinations
Supplement form Powder
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 Best Glutamine Unflavored by BPI Sports, 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:
8 Gram(s)
Maximum serving Sizes:
8 Gram(s)
Servings per container
50
UPC/BARCODE
811213022655
IngredientAmount% DV
L-Glutamine0 NP--
Vitamin C500 mg833%
Glutamic Acid0 NP--
N-Acetyl-L-Glutamine0 NP--
L-Alanyl-L-Glutamine0 NP--
Best Glutamine Blend (Proprietary)6.5 Gram(s)--
Glutamine Alpha-Ketoglutarate0 NP--
Glutamine0 NP--

Other ingredients: Citric Acid, Malic Acid, Sucralose, Acesulfame-K, Natural and Artificial flavors, Silica, Oligopeptide-Enzymatic Technology

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.
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

Rev. 01-003-BGL002 10/16

General Statements

When combined with a proper exercise and nutrition regimen. Statements based on early-stage independent 3rd party in vivo and / or in vitro model scientific research data findings for individual ingredients.

Glutamine is the most abundant amino acid (a building block for proteins) in the body, and one of the best supplements for promoting recovery and lean muscle building. Strenuous exercise can lower glutamine levels causing stress to the body and immune system. However, with proper glutamine supplementation you can help your body recover and rebuild faster.

Lean muscle Recovery

Natural and artificial flavors

New!

Essential Amino Acid for intense training

Promotes recovery Supports lean muscle Promotes Glycogen replenishment

To report an adverse event or for more information call: 954.926.0900 (tel)

Facebook www.facebook.com/BPIonline

Brand IP Statement(s)

Why is Best Glutamine better?

Best Glutamine is designed to prevent protein catabolism (the breakdown of muscle proteins) and support your efforts to train harder and longer.

Best Glutamine comes in delicious flavors to support recovery and promote lean muscle.

Be better. Be stronger. BPI.

Formula

Best Glutamine combines 6 advanced forms of Glutamine and is designed to promote a rapid rise in cellular Glutamine levels and Glutamine stores in muscle.

6 advanced forms of Glutamine

L-Glutamine Glutamine AKG Glutamic Acid N-Acetyl-L Glutamine Glutamine (as Oligopeptide Enzymatic Technology) L-Alanyl-L Glutamine

FDA Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Take 1 scoop blended into 6oz water pre/post workout

Please read entire label before use. Suggested Use: Take one (1) serving (1 scoop) with approximately 6 ounces of water or juice, or as directed by a qualified healthcare practitioner. Can be taken before, during or after workouts. On non-training days, take one (1) serving (1 scoop) first thing in the morning on an empty stomach, or as directed by a qualified healthcare practitioner.

Precautions

Warnings: Not intended for use by persons under age 18.

Do not exceed recommended dose.

Get the consent of a licensed physician before using this product, especially if you are taking medication, have a medical condition, you are pregnant, nursing or thinking about becoming pregnant.

Discontinue use two weeks prior to surgery.

Keep this product and all supplements out of the reach of children.

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

See for yourself

Best Glutamine Unflavored by BPI Sports label

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

Best Glutamine Unflavored 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 Best Glutamine Unflavored by BPI Sports

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

Serving size8 Gram(s) Dosage formPowder Servings per container50 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.

Vitamin C

Interacts with
207 drugs
500 mg per serving Form: Ascorbic Acid

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for im...

Vitamin C monograph & interactions

Best Glutamine Blend (Proprietary)

6.5 Gram(s) per serving

Other (inactive) ingredients: Citric Acid, Malic Acid, Sucralose, Acesulfame-K, Natural and Artificial flavors, Silica, Oligopeptide-Enzymatic Technology. These complete the product’s ingredient list but are not active constituents.

Interaction report

Best Glutamine Unflavored by BPI Sports Drug Interactions

Want to check YOUR meds against Best Glutamine Unflavored?

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
256Drugs
151 Moderate 105 Minor

Ingredients driving the most interactions

Vitamin C 207
L-Glutamine 50

Individual Drug Interactions

The ingredients in Best Glutamine Unflavored interact with 256 drugs. Click any drug to see the details.

2 of the 7 ingredients in Best Glutamine Unflavored interact with drugs. Each result below shows which ingredient is responsible. Vitamin C L-Glutamine

Each ingredient & the kinds of drugs it affects

For each ingredient in Best Glutamine Unflavored 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.

Vitamin C13 drug types · 207 drugs

Alkylating Agents

Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Aluminum

Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption. In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely. Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.

Likelihood Probable Evidence B
Antitumor Antibiotics

Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin. In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells. More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.

Likelihood Possible Evidence D
Estrogens

Vitamin C might increase blood levels of estrogens.
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products. It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall. When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements. Monitor these patients for estrogen-related side effects.

Likelihood Probable Evidence B
Fluphenazine (Prolixin)

Theoretically, vitamin C might decrease levels of fluphenazine.
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started. The mechanism is not known, and there is no further data to confirm this interaction.

Likelihood Possible Evidence D
Indinavir (Crixivan)

Vitamin C can modestly reduce indinavir levels.
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown.

Likelihood Probable Evidence B
Levothyroxine (Synthroid, Others)

Vitamin C can increase levothyroxine absorption.
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH.

Likelihood Probable Evidence B
Warfarin (Coumadin)

High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption. There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time. Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant. However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.

Likelihood Possible Evidence D
Acetaminophen (Tylenol, Others)

High-dose vitamin C might slightly prolong the clearance of acetaminophen.
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases. This effect is not likely to be clinically significant.

Likelihood Probable Evidence B
Aspirin

Acidification of the urine by vitamin C might increase aspirin levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction is not clinically significant.

Likelihood Possible Evidence B
Choline Magnesium Trisalicylate (Trilisate)

Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Niacin

Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% in patients with coronary disease. It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.

Likelihood Possible Evidence A
Salsalate (Disalcid)

Acidification of the urine by vitamin C might increase salsalate levels.
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels. However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion, suggesting this interaction probably is not clinically significant.

Likelihood Possible Evidence B
Vitamin C full monograph & interactions

L-Glutamine1 drug type · 50 drugs

Anticonvulsants

Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Glutamine is metabolized to the excitatory neurotransmitter glutamate. Glutamate might have antagonistic effects with anticonvulsant drugs. However, this interaction has not yet been reported in humans.

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

Brand information

Manufacturer and brand details for Best Glutamine Unflavored, from the product label.

BPI Sports

See all BPI Sports products
Name
BPI Sports
Street Address
3149 SW 42nd St. Suite 200
City
Hollywood
State
FL
ZipCode
33312
Phone Number
954.926.0900
Web Address
www.bpisports.com
Pharmacist Counseling Corner

Best Glutamine Unflavored by BPI Sports: Common Questions

Does Best Glutamine Unflavored by BPI Sports interact with any medications?
Yes. Based on its ingredients, Best Glutamine Unflavored has a known interaction with 256 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
Best Glutamine Unflavored 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.
What does glutamine do in my body?
Glutamine is an amino acid your body uses to build and repair muscle, support your gut, and help you recover after stress, illness, or intense exercise. It's especially important after surgery or for muscle wasting from conditions like HIV/AIDS.
Can I take this if I'm pregnant or breastfeeding?
The glutamine in this product is rated likely safe in pregnancy and lactation. Vitamin C from normal food and prenatal vitamins is fine, but avoid high-dose supplements unless your doctor recommends them. Talk with your doctor or pharmacist about what's safe for you personally.
What side effects might I get from this powder?
The most common are belly symptoms—bloating, gas, constipation, diarrhea, or discomfort—plus nausea, headache, and cough. Higher doses can make these worse. Rarely, dizziness has been reported. If you have bipolar disorder, watch for unusual mood changes and let your doctor know.
Is this safe if I have kidney or liver problems?
No—people with kidney or liver disease should only use glutamine under a doctor's supervision. The same applies to very high doses of vitamin C if you're prone to kidney stones. Talk with your doctor before starting.
Will this powder help my athletic recovery?
Glutamine is possibly effective for recovery after surgery and after critical illness from trauma, so it may help with recovery. The evidence for athletic performance or muscle building specifically isn't established in the data we hold, but you can ask your coach or sports doctor for their take.
What's in this powder besides the active ingredients?
The rest are inactive ingredients—fillers and flavor enhancers like citric acid, malic acid, sucralose, acesulfame-K, natural and artificial flavors, silica, and an enzyme technology. They help the powder mix and taste better.

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.

Best Glutamine Unflavored label
Go deeper

The Full Monographs Behind Best Glutamine Unflavored’s Ingredients

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

Herb & supplement monograph

Vitamin C

Interacts with 207 drugs

Vitamin C (ascorbic acid) is an essential nutrient your body needs but cannot make, so you must get it from food or supplements. It's important for immune function, collagen, and acts as an...

Read the full Vitamin C monograph → Herb & supplement monograph

Glutamine

Interacts with 50 drugs

Glutamine is the most abundant amino acid in the body and is usually made in your muscles. A prescription form is FDA-approved to help reduce sickle cell disease complications, but for most...

Read the full Glutamine monograph →
Sources

Sources & How We Checked

Best Glutamine Unflavored'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 62 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.

Glutamine 11 references
  1. Miller AL. Therapeutic considerations of L-glutamine: a review of the literature. Altern Med Rev 1999;4:239-48..
  2. Bozzetti F, Biganzoli L, Gavazzi C, et al. Glutamine supplementation in cancer patients receiving chemotherapy: a double-blind randomized study. Nutrition 1997;13:748-51.. PubMed
  3. Mebane AH. L-Glutamine and mania. Am J Psychiatry 984;141:1302-3.
  4. Meldrum BS. Glutamate as a neurotransmitter in the brain: review of physiology and pathology. J Nutr 2000;130:1007S-15S.. PubMed
  5. Garlick PJ. Assessment of the safety of glutamine and other amino acids. J Nutr 2001;131:2556S-61S.. PubMed
  6. Chapman AG. Glutamate and epilepsy. J Nutr 2000;130:1043S-5S.. PubMed
  7. Ziegler TR. Glutamine supplementation in cancer patients receiving bone marrow transplantation and high dose chemotherapy. J Nutr 2001;131:2578S-84S.. PubMed
  8. Laviano A, Molfino A, Lacaria MT, Canelli A, De Leo S, Preziosa I, Rossi Fanelli F. Glutamine supplementation favors weight loss in nondieting obese female patients. A pilot study. Eur J Clin Nutr. 2014 Nov;68(11):1264-6. PubMed
  9. Endari (l-glutamine) [package insert]. Torrance, CA: Emmaus Medical,Inc; 2017.
  10. Niihara Y, Miller ST, Kanter J, et al. A Phase 3 Trial of l-Glutamine in Sickle Cell Disease. N Engl J Med 2018;379(3):226-35. doi: 10.1056/NEJMoa1715971.
  11. Ogden HB, Child RB, Fallowfield JL, et al. Gastrointestinal Tolerance of Low, Medium and High Dose Acute Oral l-Glutamine Supplementation in Healthy Adults: A Pilot Study. Nutrients. 2020;12(10):2953. PubMed

See these in context on the Glutamine monograph →

Vitamin C 51 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Back DJ, Breckenridge AM, MacIver M, et al. Interaction of ethinyloestradiol with ascorbic acid in man. Br Med J (Clin Res Ed) 1981;282:1516.
  3. Morris JC, Beeley L, Ballantine N. Interaction of ethinyloestradiol with ascorbic acid in man [letter]. Br Med J (Clin Res Ed) 1981;283:503.
  4. Labriola D, Livingston R. Possible interactions between dietary antioxidants and chemotherapy. Oncology 1999;13:1003-8.
  5. Dwyer JH, Merz NB, Shirocre AM, et al. Progression of early atherosclerosis and intake of vitamin C and vitamin E from supplements and food. The Los Angeles Atherosclerosis Study. 41st Annual Conference on Cardiovascular Disease Epidemiology and Prevent
  6. Levine M, Rumsey SC, Daruwala R, et al. Criteria and recommendations for vitamin C intake. JAMA 1999;281:1415-23. PubMed
  7. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  8. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  9. Food and Nutrition Board, Institute of Medicine. Dietary Reference Intakes for Vitamin C, Vitamin E, Selenium, and Carotenoids. Washington, DC: National Academy Press, 2000. Available at: http://www.nap.edu/books/0309069351/html/.
  10. Houston JB, Levy G. Drug biotransformation interactions in man VI: Acetaminophen and ascorbic acid. J Pharm Sci 1976;65:1218-21. PubMed
  11. Brown BG, Zhao XQ, Chait A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med 2001;345:1583-93. DOI
  12. Rosenthal G. Interaction of ascorbic acid and warfarin. JAMA 1971;215:1671. DOI
  13. Hume R, Johnstone JM, Weyers E. Interaction of ascorbic acid and warfarin. JAMA 1972;219:1479. DOI
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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