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Dietary supplement

L-Glutamine Ingredients & Drug Interactions

by GNC Mega Men

Other (e.g. Tea Bag) Category: Amino Acid/protein
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

L-Glutamine is a dietary supplement by GNC Mega Men 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 by GNC Mega Men

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 product contains one active ingredient: L-glutamine, an amino acid your body naturally makes and uses for immune function, gut health, and muscle recovery. GNC Mega Men L-Glutamine also includes two inactive ingredients — dicalcium phosphate and cellulose — which serve as a binder and filler to hold the supplement 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: Supports recovery with glutamine.
  • We looked for evidence on: Athletic performance, Exercise-induced muscle damage, Postoperative recovery, Wound healing, Critical illness (trauma), Burns — and 3 related terms.
  • The strongest evidence on file: Glutamine is rated "Possibly Effective" for Critical illness (trauma) (Natural Medicines).
  • Also on file: Glutamine is rated "Possibly Effective" for Postoperative recovery.
  • Also on file: Glutamine is rated "Possibly Ineffective" for Athletic performance, Burns, Radiation-induced diarrhea.

L-glutamine is rated effective for sickle cell disease. It's considered possibly effective for HIV/AIDS-related wasting, postoperative recovery, and critical illness from trauma.

The evidence we hold doesn't establish whether it works for other uses outside those categories.

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 by healthy adults. Common side effects include belching, bloating, gas, constipation, diarrhea, stomach pain, nausea, vomiting, headache, cough, and muscle or joint pain — especially at higher doses.

A small number of people have reported dizziness or, rarely, mood changes (mania or hypomania) when taking it; one case of dizziness resolved when the dose was reduced. If you have kidney or liver disease, use it only under medical supervision.

The safety data for pregnancy is considered likely safe. There isn't enough reliable safety information for breastfeeding, so talk with your doctor or pharmacist before taking it while nursing.

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 anticonvulsants (seizure medications), check with your doctor or pharmacist before starting this supplement. Glutamine might theoretically reduce how well these drugs work, though this hasn't been confirmed in people.

The interaction severity is Moderate, so it's worth confirming your exact medications before you begin.

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.

L-glutamine may help with sickle cell disease and might support recovery after surgery or serious illness, though the evidence for those uses is less established. The main caution is if you take seizure medications — check with your doctor or pharmacist first.

Side effects are usually mild and digestive. It's generally well tolerated in healthy adults.

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 Feb 23, 2012.

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, straight from the product label.

Brand GNC Mega Men
Net contents 30 Pack(s)
Market status On market
Date entered into DSLD Feb 23, 2012
DSLD ID 5888
Product type Amino Acid/protein
Supplement form Other (e.g. Tea Bag)
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Adult Male (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 by GNC Mega Men, 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:
1 Caplet(s)
Maximum serving Sizes:
1 Caplet(s)
IngredientAmount% DV
L-Glutamine1000 mg--

Other ingredients: Dicalcium Phosphate, Cellulose

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 Statement of Identity

Dietary Supplement

Suggested/Recommended/Usage/Directions

Directions: As a dietary supplement, take the contents of one pack daily with food.

Brand IP Statement(s)

Dr. Frank J. Costa, M.D., an internationally acclaimed urological surgeon and men’s health expert, is part of the GNC Medical Advisory Board. One of “America’s Top Physicians,” Dr. Costa lectures nationally and internationally on men’s health topics. Dr. Costa is regularly featured in television, radio and newspaper interviews and has published articles in both professional journals and popular magazines. “Proper nutrition is essential for optimal athletic performance. I recommend the Mega Men(R) Sport Vitapak(R) Program. It provides a strategic combination of vitamins, minerals and other nutrients to fuel performance while supporting good health." Dr. Frank J. Costa MD (signature)

MegaNatural(R)-BP(TM) and MegaNatural(R) Gold and their logos are trademarks of Constellation Wines U.S., Inc.

Formulation

No Artificial Colors, No Wheat, No Gluten, No Dairy, Yeast Free.

Formula

Supports recovery with glutamine*

General Statements

Sport

GNC QUALITY COMMITMENT GNC, the leader in the development and manufacture of dietary supplements, is committed to producing the highest quality products available. This commitment begins with quality designed supplement formulations. Every raw material that goes into a GNC supplement is guaranteed as to quality and potency. Each product is dated and then shipped immediately to our stores, so you can be sure you are purchasing the freshest supplements available. At GNC, we extend our quality commitment to you by offering our money-back guarantee.

GNC GUARANTEE Use any GNC supplement for as little as 10 days. If you are not 100% completely satisfied, return the unused portion of the product with proof of purchase to your GNC store for a complete refund of your purchase price. No questions asked!

Each pack contains:

CLINICALLY STUDIED^

ACTUAL SIZE

Conforms to USP <2091> for weight. Meets USP <2040> for disintegration.

L-Glutamine

L-Glutamine – An important amino acid that plays a pivotal role in the nitrogen balance in the body, provides an anti-catabolic effect and is involved in protein synthesis and hydrating muscle cells.* Glutamine levels in the body are drastically reduced with intense exercise and supplementing with L-glutamine can help the body maintain glutamine levels and maximize your muscle function.*

Potency verified by GNC procedure #5052.

Precautions

WARNING: Consult your physician prior to using this product if you are pregnant, nursing, taking medication, or have a medical condition. Discontinue use two weeks prior to surgery.

KEEP OUT OF REACH OF CHILDREN.

General

CODE 328211 CMG

Storage

Store in a cool, dry place.

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 by GNC Mega Men label

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

What’s inside

The Ingredients in L-Glutamine by GNC Mega Men

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

Serving size1 Caplet(s) Dosage formOther (e.g. Tea Bag) Amounts shown are per serving.

L-Glutamine

Interacts with
50 drugs
1000 mg 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: Dicalcium Phosphate, Cellulose. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Glutamine by GNC Mega Men Drug Interactions

Want to check YOUR meds against L-Glutamine?

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 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, from the product label.

GNC Mega Men

See all GNC Mega Men products
Phone Number
1-888-462-2548
Pharmacist Counseling Corner

L-Glutamine by GNC Mega Men: Common Questions

Does L-Glutamine by GNC Mega Men interact with any medications?
Yes. Based on its ingredients, L-Glutamine 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 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.
Is L-glutamine safe during pregnancy?
Yes — the safety data rates L-glutamine as likely safe in pregnancy. However, individual circumstances vary, so let your doctor know you're taking it.
Is it safe to take while breastfeeding?
There isn't enough reliable safety data to know either way. Talk with your doctor or pharmacist before taking it while nursing — they can weigh the benefits and risks for your situation.
What are the most common side effects?
Digestive complaints like belching, bloating, gas, constipation, diarrhea, stomach pain, and nausea are the most frequent. Headache, cough, and muscle pain have also been reported. Most are mild and more common at higher doses.
Does L-glutamine actually work?
It's proven effective for sickle cell disease. For other uses like surgery recovery or wound healing, the evidence is promising but not yet established enough to say it definitely works.
Who should be careful taking this supplement?
People with kidney or liver disease should only use it under medical supervision. Anyone taking seizure medications should check with their doctor or pharmacist first. If you have bipolar disorder, talk with your healthcare provider, as a couple of cases of mood changes have been reported.

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

Not sure if L-Glutamine 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 label
Sources

Sources & How We Checked

L-Glutamine'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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