L-Glutamine 500 mg Ingredients & Drug Interactions
by Quest
What is this page for?
First and foremost: checking L-Glutamine 500 mg 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
L-Glutamine 500 mg is a dietary supplement by Quest 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.
Check Your Meds Against L-Glutamine 500 mg by Quest
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Glutamine 500 mg by Quest — and tell you which ingredient is responsible.
AI summaries are generated from our interaction database for education only — always confirm with your pharmacist. How we use AI
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HelloPharmacist Scorecard of L-Glutamine 500 mg by Quest
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.
What’s inside
Full disclosure
Quest L-Glutamine 500 mg contains one active ingredient: L-glutamine, an amino acid your body uses for intestinal health, immune function, and recovery from physical stress. The capsule also holds microcrystalline cellulose, magnesium stearate, and gelatin as inactive ingredients (binders and capsule material).
Does it work?
Moderate evidence
The evidence for L-glutamine varies by use. It's rated effective for sickle cell disease.
For HIV/AIDS-related wasting, postoperative recovery, and critical illness from trauma, the evidence is rated possibly effective — meaning there's promise, but more research is needed. The data we hold doesn't establish effectiveness for other common uses you might see advertised.
How safe is it?
Well-documented data
Orally, L-glutamine is generally well tolerated. The most common side effects are digestive — belching, bloating, constipation, diarrhea, flatulence, nausea, vomiting, and stomach pain.
Headache and musculoskeletal pain have also been reported. A few rare cases of dizziness and neurological symptoms (mania or hypomania) appeared in people with bipolar disorder taking higher doses.
There isn't enough reliable safety data, so you should avoid supplemental doses unless your doctor recommends them. If you have kidney or liver disease, use it only under medical supervision.
During breastfeeding, little safety information exists — talk with your doctor or pharmacist before taking it. Pregnancy is rated likely safe, but confirm with your healthcare provider.
Meds to double-check
Moderate interaction found
Before you take this product, check with your doctor or pharmacist if you take anticonvulsants (anti-seizure medications). The concern is theoretical — glutamine might antagonize how these drugs work — but it hasn't been reported in humans yet.
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 has solid evidence for sickle cell disease and some promise for recovery after surgery or critical illness. The main concern is a theoretical interaction with anticonvulsants — one to run past your doctor or pharmacist if that applies to you.
It's generally well tolerated but can cause digestive upset, and people with kidney or liver disease need medical supervision. Talk with your own healthcare provider about whether it fits your situation.
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 Jul 25, 2013.
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
General information
Key facts about L-Glutamine 500 mg, straight from the product 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 500 mg by Quest, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Glutamine | 500 mg | -- |
Other ingredients: Microcrystalline Cellulose, Magnesium Stearate, Gelatin
Tap any ingredient to jump to its full detail below.
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.
Suggested/Recommended/Usage/Directions
Recommended Use: Helps restore plasma glutamine levels depleted after periods of physical stress (e.g. prolonged exhaustive exercise). Helps support digestive and immune system health after periods of physical stress. Helps to assist in muscle cell repair after exercise. Recommended Dose (Adults): Take 5 capsules twice daily.
Precautions
Risk Information: Consult a health care practitioner prior to use if you are pregnant, breastfeeding or following a low protein diet.
KEEP OUT OF REACH OF CHILDREN.
DO NOT USE IF SEAL UNDER CAP IS BROKEN.
Formulation
This product does not contain corn, dairy, egg, gluten, shellfish, soy or sulfites.
No artificial colours, flavours or preservatives
Storage
STORE IN A COOL, DRY PLACE.
General Statements
WELLNESS
Helps muscle cell repair after exercise
A Proud Canadian Company
Seals/Symbols
PREMIUM - QUALITY ASSURED
{Recycle}
SunOpta A healthy products company
General
338439.01-04
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Glutamine 500 mg by Quest label
The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.
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)The Ingredients in L-Glutamine 500 mg by Quest
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Capsule(s) Dosage formCapsule Amounts shown are per serving.
L-Glutamine
Interacts with50 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 c...
L-Glutamine monograph & interactionsOther (inactive) ingredients: Microcrystalline Cellulose, Magnesium Stearate, Gelatin. These complete the product’s ingredient list but are not active constituents.
L-Glutamine 500 mg by Quest Drug Interactions
HelloPharmacist Interaction Report
Quest L-Glutamine 500 mg has one documented interaction category: anticonvulsants (anti-seizure medications).
The concern is theoretical — glutamine is broken down into glutamate, an excitatory brain chemical that might work against how anticonvulsants calm seizure activity. However, this interaction has not been reported in actual human use.
Read the full breakdown — every affected drug type, severity by severity
If you take anticonvulsants, this is worth a conversation with your doctor or pharmacist before you start. Altogether, these interactions span 50 individual medications.
No other interactions are documented in our data for the ingredients we could check. That said, the absence of documented interactions is not a guarantee that none exist — it means we haven't found reports of them.
Use the medication checker on this page to look up your exact drugs, and run the list past your own healthcare provider or pharmacist.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Glutamine 500 mg?
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 checkerIngredients driving the most interactions
Individual Drug Interactions
The ingredients in L-Glutamine 500 mg interact with 50 drugs. Click any drug to see the details.
1 of the 1 ingredient in L-Glutamine 500 mg interact with drugs. Each result below shows which ingredient is responsible. L-Glutamine
AcetazolamideAk-Zol, Diamox
How Acetazolamide interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Acetazolamide interactionAminophylline, Amobarbital, EphedrineAmesec
How Aminophylline, Amobarbital, Ephedrine interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Aminophylline, Amobarbital, Ephedrine interactionAmobarbitalAmytal
How Amobarbital interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Amobarbital interactionAmobarbital, Ephedrine SulfateEphedrine & Amytal
How Amobarbital, Ephedrine Sulfate interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Amobarbital, Ephedrine Sulfate interactionAmobarbital, SecobarbitalTuinal
How Amobarbital, Secobarbital interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Amobarbital, Secobarbital interactionAprobarbital, Butabarbital, PhenobarbitalTriple Barbital
How Aprobarbital, Butabarbital, Phenobarbital interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Aprobarbital, Butabarbital, Phenobarbital interactionBelladonna, Caffeine, Ergotamine, PentobarbitalMicomp PB
How Belladonna, Caffeine, Ergotamine, Pentobarbital interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Belladonna, Caffeine, Ergotamine, Pentobarbital interactionBelladonna, PhenobarbitalBellophen, Susano
How Belladonna, Phenobarbital interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Belladonna, Phenobarbital interactionBellafoline, Caffeine, Ergotamine Tartrate, PentobarbitalCafergot PB
How Bellafoline, Caffeine, Ergotamine Tartrate, Pentobarbital interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Bellafoline, Caffeine, Ergotamine Tartrate, Pentobarbital interactionButalbital, Phenobarbital, SecobarbitalTribarb
How Butalbital, Phenobarbital, Secobarbital interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Butalbital, Phenobarbital, Secobarbital interactionCarbamazepineCarbatrol, Carnexiv, Equetro, Tegretol, Tegretol XR
How Carbamazepine interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Carbamazepine interactionCenobamateXcopri
How Cenobamate interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Cenobamate interactionClobazamFrisium, Onfi, Sympazan
How Clobazam interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Clobazam interactionClonazepamCeberclon, Klonopin, Rivotril
How Clonazepam interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Clonazepam interactionClorazepateTranxene, Tranxene SD, Tranxene T-Tab
How Clorazepate interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Clorazepate interactionDiazepamDiastat AcuDial, Valium, Valium injection, Valtoco
How Diazepam interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Diazepam interactionDivalproex SodiumDepakote
How Divalproex Sodium interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Divalproex Sodium interactionEphedrine, Phenobarbital, TheophyllineTedral
How Ephedrine, Phenobarbital, Theophylline interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Ephedrine, Phenobarbital, Theophylline interactionEthosuximideZarontin
How Ethosuximide interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Ethosuximide interactionEthotoinPaganone
How Ethotoin interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Ethotoin interactionFelbamateFelbatol
How Felbamate interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Felbamate interactionFosphenytoinCerebyx
How Fosphenytoin interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Fosphenytoin interactionFosphenytoin SodiumSesquient
How Fosphenytoin Sodium interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Fosphenytoin Sodium interactionGabapentinGralise, Neurontin
How Gabapentin interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Gabapentin interactionGabapentin EnacarbilHorizant
How Gabapentin Enacarbil interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Gabapentin Enacarbil interactionLamotrigineLamictal
How Lamotrigine interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Lamotrigine interactionLevetiracetamElepsia XR, Keppra, Spritam
How Levetiracetam interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Levetiracetam interactionLorazepamAtivan
How Lorazepam interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Lorazepam interactionMagnesium Sulfate (prescription Drug)Bilagog, Magnesium Sulfate
How Magnesium Sulfate (prescription Drug) interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Magnesium Sulfate (prescription Drug) interactionMephenytoinMesantoin
How Mephenytoin interacts with L-Glutamine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-glutamineAnticonvulsants Moderate
Interaction Summary
Theoretically, glutamine might antagonize the effects of anticonvulsant medications.
Read the full L-glutamine + Mephenytoin interactionEach ingredient & the kinds of drugs it affects
For each ingredient in L-Glutamine 500 mg 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-Glutamine
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.
Brand information
Manufacturer and brand details for L-Glutamine 500 mg, from the product label.
Quest
See all Quest products- Name
- SunOpta Inc.
- Street Address
- 6 Commerce Crescent
- City
- Acton
- State
- ON
- ZipCode
- L7J 2X3
L-Glutamine 500 mg by Quest: Common Questions
Does L-Glutamine 500 mg by Quest interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Does L-glutamine really work?
What side effects should I expect?
Is it safe to take while pregnant or breastfeeding?
Can I take this if I have kidney or liver disease?
What is L-glutamine used for in the body?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Glutamine 500 mg is safe with your meds?
Our pharmacists answer your medication & supplement questions — free.
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.
The Full Monographs Behind L-Glutamine 500 mg’s Ingredients
Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.
Sources & How We Checked
L-Glutamine 500 mg'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.
- NIH Dietary Supplement Label Database (DSLD) — The official product label on file for this supplement.
- Natural Medicines (Therapeutic Research Center) — Evidence-graded clinical reference behind the ingredient interaction data.
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
- Miller AL. Therapeutic considerations of L-glutamine: a review of the literature. Altern Med Rev 1999;4:239-48..
- 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
- Mebane AH. L-Glutamine and mania. Am J Psychiatry 984;141:1302-3.
- Meldrum BS. Glutamate as a neurotransmitter in the brain: review of physiology and pathology. J Nutr 2000;130:1007S-15S.. PubMed
- Garlick PJ. Assessment of the safety of glutamine and other amino acids. J Nutr 2001;131:2556S-61S.. PubMed
- Chapman AG. Glutamate and epilepsy. J Nutr 2000;130:1043S-5S.. PubMed
- Ziegler TR. Glutamine supplementation in cancer patients receiving bone marrow transplantation and high dose chemotherapy. J Nutr 2001;131:2578S-84S.. PubMed
- 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
- Endari (l-glutamine) [package insert]. Torrance, CA: Emmaus Medical,Inc; 2017.
- 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.
- 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
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