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Dietary supplement

L-Glutamine 5000 mg Unflavored Ingredients & Drug Interactions

by GNC Pro Performance

Powder Category: Amino Acid/protein
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

L-Glutamine 5000 mg Unflavored is a dietary supplement by GNC Pro Performance with 1 active ingredient. Its ingredients are commonly taken for muscle recovery and sports performance, gut health and 'leaky gut', recovery from severe illness or injury.Based on those ingredients, 50 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are L-Glutamine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of L-Glutamine 5000 mg Unflavored by GNC Pro Performance

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

From our pharmacy team — supplement deep dive

What’s inside

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 1 of its 1 active ingredient.
  • No proprietary blends here — you can verify the dose of every single component.

This is a straightforward single-ingredient product: 5,000 mg of L-glutamine per serving, an amino acid your body makes naturally. L-glutamine is used by your cells for energy and immune function, and it plays a role in gut health and muscle recovery.

There are no inactive ingredients listed.

Does it work?

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

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

Why this rating?
  • The label markets this product for: muscle recovery and immune support.
  • We looked for evidence on: Exercise-induced muscle damage, Athletic performance, Critical illness (trauma), Postoperative recovery, Wound healing, HIV/AIDS-related wasting — and 4 related terms.
  • The strongest evidence on file: Glutamine is rated "Effective" for Sickle cell disease (Natural Medicines).
  • Also on file: Glutamine is rated "Possibly Effective" for HIV/AIDS-related wasting, Critical illness (trauma), Postoperative recovery.
  • Also on file: Glutamine is rated "Possibly Ineffective" for Athletic performance, Radiation-induced diarrhea.

The evidence for L-glutamine is strongest for sickle cell disease, where it's rated effective. For HIV/AIDS-related wasting, postoperative (after-surgery) recovery, and critical illness from trauma, the evidence is rated possibly effective — meaning the studies suggest it may help, but more research is needed to be sure.

We hold no effectiveness data for other uses.

The evidence, ingredient by ingredient 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 1 of the 1 matched ingredient.
  • Pregnancy & breastfeeding safety ratings cover 1 of 1.
  • General safety write-ups exist for 1 of 1.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

L-glutamine is generally well tolerated in healthy adults. The most common side effects are digestive — belching, bloating, constipation, diarrhea, flatulence, nausea, and vomiting — as well as headache and musculoskeletal pain.

People with kidney or liver disease should only use it under medical supervision. If you have bipolar disorder, know that mania and hypomania have been reported rarely in patients taking glutamine.

Pregnancy and lactation safety is rated likely safe, though not enough data exists for supplemental doses while breastfeeding unless your doctor advises otherwise.

Side effects, ingredient by ingredient 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?
  • 1 of the 1 matched ingredient can interact with medications — Glutamine.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: seizure medications.
  • For scale: 50 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.

If you take anticonvulsant medications (seizure drugs), double-check with your doctor or pharmacist before adding this product — glutamine may theoretically reduce how well they work, though no human cases have been reported yet.

Check your own medication Run your meds through the checker above

The bottom line

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

L-glutamine may be worth considering if you have sickle cell disease or are recovering from surgery or critical illness, but the evidence for other uses isn't established in our data. The main concern is a theoretical interaction with anticonvulsants — if that's you, talk it over with your doctor or pharmacist before starting.

Digestive side effects are common, so start low and see how you feel.

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

Assessment coverage: 1 of 1 active ingredient matched to our full ingredient reviews (monographs). Based on the product label dated May 22, 2020.

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 L-Glutamine 5000 mg Unflavored, straight from the product label.

Brand GNC Pro Performance
Barcode (UPC) 048107169831
Net contents 32 Oz(s); 2 lb(s); 907 Gram(s)
Market status On market
Date entered into DSLD May 22, 2020
DSLD ID 220100
Product type Amino Acid/protein
Supplement form Powder
Dietary claims / uses All Other, Structure/Function
Intended target group(s) Adult (18 - 50 Years), Gluten Free, Dairy Free
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 L-Glutamine 5000 mg Unflavored by GNC Pro Performance, 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:
5 Gram(s)
Maximum serving Sizes:
5 Gram(s)
Servings per container
181
UPC/BARCODE
048107169831
IngredientAmount% DV
L-Glutamine5 Gram(s)--

Other ingredients: None

Tap any ingredient to jump to its full detail below.

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

Pro Performance Results Supplementation may help maintain glutamine levels that have been depleted as a result of intense exercise. Glutamine is involved in protein synthesis and plays a pivotal role in the body's nitrogen balance. It serves as fuel for the immune system and maintenance of proper intestinal function. When used in conjunction with an exercise program.

Pro Performance Quality Pro Performance L-Glutamine is tested and certified Banned Substance Free. It is gluten free, lactose free and mixed easily with your favorite beverage.

Key Amino Acid for muscles Fuels the immune system

Gluten free, lactose free.

Products bearing this logo have been tested for banned substances by LGC Science, Inc., a world-class anti-doping lab. Product was tested for over 145 banned substances on the 2017 World Anti-Doping Agency (WADA) Prohibited List via LGC skip lot testing protocol #ICP0307. See gnc.com for more information.

Precautions

Keep out of reach of children.

Storage

Store in a cool, dry place.

Seals/Symbols

Banned Substance Free

Informedchoice.org Trusted by sport

FDA Statement of Identity

Dietary Supplement

General Statements

181 Servings

Notice: Significant product settling may occur.

Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement, mix one scoop (5 g) twice daily in a beverage or shake. For maximum results, take one serving (5g) post-exercise.

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.

See for yourself

L-Glutamine 5000 mg Unflavored by GNC Pro Performance label

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

What’s inside

The Ingredients in L-Glutamine 5000 mg Unflavored by GNC Pro Performance

This is the 1 active ingredient this product is made of. Select it to open its full monograph.

Serving size5 Gram(s) Dosage formPowder Servings per container181 Amounts shown are per serving.

L-Glutamine

Interacts with
50 drugs
5 Gram(s) per serving

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 c...

L-Glutamine monograph & interactions

Other (inactive) ingredients: None. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Glutamine 5000 mg Unflavored by GNC Pro Performance Drug Interactions

Want to check YOUR meds against L-Glutamine 5000 mg 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
50Drugs
50 Moderate

Ingredients driving the most interactions

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Glutamine 5000 mg Unflavored with known interactions, here are the types of medications it can affect. Open any type for the detail — or search your exact drug in the checker above.

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
The maker

Brand information

Manufacturer and brand details for L-Glutamine 5000 mg Unflavored, from the product label.

GNC Pro Performance

See all GNC Pro Performance products
Name
General Nutrition Corporation
City
Pittsburgh
State
PA
ZipCode
15222
Phone Number
1-888-462-2548
Web Address
gnc.com
Pharmacist Counseling Corner

L-Glutamine 5000 mg Unflavored by GNC Pro Performance: Common Questions

Does L-Glutamine 5000 mg Unflavored by GNC Pro Performance interact with any medications?
Yes. Based on its ingredients, L-Glutamine 5000 mg Unflavored has a known interaction with 50 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
L-Glutamine 5000 mg Unflavored contains a single active ingredient, and that one ingredient can interact with many different medications on its own. We check it against each medication and show the mechanism 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 is L-glutamine and why would I take it?
L-glutamine is an amino acid that your body produces naturally. It's used by your cells for energy, immune support, and gut health. It's most clearly effective for sickle cell disease and may help with recovery after surgery or during critical illness, though the evidence for those uses is still developing.
What side effects should I expect?
Digestive upset is most common — bloating, gas, constipation, diarrhea, nausea, and vomiting. Headache and muscle pain have also been reported. Dizziness is rare but has occurred; if it does, lowering your dose may help. In people with bipolar disorder, mood changes (mania or hypomania) have been reported rarely.
Is it safe if I'm pregnant or breastfeeding?
L-glutamine is rated likely safe during pregnancy. For breastfeeding, there isn't enough data to know either way — talk with your doctor or pharmacist about whether to take it while nursing.
Can I take this if I have kidney or liver disease?
Only under medical supervision. If you have either condition, check with your doctor or pharmacist before starting this supplement.
Does this product have any fillers or other ingredients?
No — this is unflavored powder with L-glutamine only and no other inactive ingredients listed.

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

Not sure if L-Glutamine 5000 mg Unflavored is safe with your meds?

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Ask a pharmacist

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.

L-Glutamine 5000 mg Unflavored label
Go deeper

The Full Monographs Behind L-Glutamine 5000 mg Unflavored’s Ingredients

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

Sources

Sources & How We Checked

L-Glutamine 5000 mg 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 11 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 →

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

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

© 2021 Therapeutic Research Center, LLC

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