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Dietary supplement

L-Glutamine Powder Ingredients & Drug Interactions

by Douglas Laboratories

L-Glutamine Powder label
See full label image
Powder Category: Amino Acid/protein
Most serious interaction: Moderate
Clinical methodology reviewed by · Updated Sep 9, 2026 · Label data from the NIH DSLD
What is this page for?

First and foremost: checking L-Glutamine Powder 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

L-Glutamine Powder is a dietary supplement by Douglas Laboratories 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.

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Check Your Meds Against L-Glutamine Powder by Douglas Laboratories

Ask about any prescription or over-the-counter medication and we check it for interactions with L-Glutamine Powder by Douglas Laboratories — and tell you which ingredient is responsible.

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HelloPharmacist Scorecard of L-Glutamine Powder by Douglas Laboratories

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

From our pharmacy team — supplement deep dive

Generated from HelloPharmacist’s pharmacist-curated databases and editorial rules · Last generated Jul 11, 2026

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 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 makes naturally. L-glutamine plays a role in immune function, gut health, and muscle metabolism.

Douglas Laboratories' formula is just the amino acid itself in powder form, with no inactive fillers or other 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

This product doesn't appear to be marketed for a specific use, so we graded Glutamine's overall clinical evidence instead.

Strong

Strong clinical evidence supports Glutamine for:

Why this rating?
  • We looked at the product name, claims, and label statements and couldn't find a stated purpose to grade.
  • Since the label doesn't commit to one use, we graded the ingredient's overall clinical evidence instead.
  • On file: Sickle cell disease — rated "Effective" (Natural Medicines).
  • On file: HIV/AIDS-related wasting — rated "Possibly Effective" (Natural Medicines).
  • On file: Critical illness (trauma) — rated "Possibly Effective" (Natural Medicines).
  • On file: Postoperative recovery — rated "Possibly Effective" (Natural Medicines).
  • On file: Pancreatitis — rated "Possibly Effective" (Natural Medicines).

L-glutamine is rated effective for sickle cell disease. For HIV/AIDS-related wasting, postoperative recovery, and critical illness from trauma, the evidence is considered possibly effective — meaning there's some promise, but we'd need more research to be certain.

The data we hold doesn't establish effectiveness 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 from oral use are digestive — belching, bloating, constipation, diarrhea, flatulence, and nausea — though these tend to be mild.

Headache and musculoskeletal pain have also been reported. If you have kidney or liver disease, use this supplement only under medical supervision.

Safety data in pregnancy is rated as likely safe. However, there isn't enough reliable safety information for breastfeeding, so talk with your doctor or pharmacist before using it while nursing.

In rare cases, people with bipolar disorder have reported mood changes (mania or hypomania); if this applies to you, discuss it with your clinician first.

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 us before starting — glutamine may theoretically reduce their effectiveness, though this hasn't been proven in humans yet.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with strong clinical evidence behind its ingredients' uses. 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, or if a doctor recommends it for HIV/AIDS-related wasting. If you take seizure medications, check with us first.

Anyone with kidney or liver disease should only use it under medical supervision.

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 Oct 24, 2024.

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 Powder, straight from the product label.

Brand Douglas Laboratories
Barcode (UPC) 310539004722
Net contents 266.6 Gram(s); 9.4 Ounce(s)
Market status On market
Date entered into DSLD Oct 24, 2024
DSLD ID 317995
Product type Amino Acid/protein
Supplement form Powder
Dietary claims / uses All Other
Intended target group(s) Adult (18 - 50 Years), Gluten 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 Powder by Douglas Laboratories, 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:
4.3 Gram(s)
Maximum serving Sizes:
4.3 Gram(s)
Servings per container
62
UPC/BARCODE
310539004722
IngredientAmount% DV
L-Glutamine4 Gram(s)--

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.
Suggested/Recommended/Usage/Directions

Suggested usage: As a dietary supplement, adults mix one heaping teaspoon in water or juice, twice daily or as directed by your health professional.

Precautions

Warning: If you are pregnant, nursing, have any health condition or taking any medication, consult your health professional before using this product.

Keep out of the reach of children.

Use only if safety seal is intact.

Storage

Store in a cool, dry place.

Packaged by weight, not volume. Settling may occur.

Formulation

Gluten-free, Non-GMO

General Statements

Scan to learn about our manufacturing excellence

FDA Statement of Identity

Dietary Supplement

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

See for yourself

L-Glutamine Powder by Douglas Laboratories label

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

L-Glutamine Powder 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 L-Glutamine Powder by Douglas Laboratories

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

Serving size4.3 Gram(s) Dosage formPowder Servings per container62 Amounts shown are per serving.

L-Glutamine

Interacts with
50 drugs
4 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
Interaction report

L-Glutamine Powder by Douglas Laboratories Drug Interactions

Want to check YOUR meds against L-Glutamine Powder?

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

L-Glutamine 50

Individual Drug Interactions

The ingredients in L-Glutamine Powder interact with 50 drugs. Click any drug to see the details.

1 of the 1 ingredient in L-Glutamine Powder interact with drugs. Each result below shows which ingredient is responsible. L-Glutamine

Each ingredient & the kinds of drugs it affects

For each ingredient in L-Glutamine Powder 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
L-Glutamine full monograph & interactions
The maker

Brand information

Manufacturer and brand details for L-Glutamine Powder, from the product label.

Douglas Laboratories

See all Douglas Laboratories products
Name
Douglas Laboratories
City
Sudbury
State
MA
ZipCode
01776
Phone Number
1.800.245.4440
Web Address
www.douglaslabs.com
Pharmacist Counseling Corner

L-Glutamine Powder by Douglas Laboratories: Common Questions

Does L-Glutamine Powder by Douglas Laboratories interact with any medications?
Yes. Based on its ingredients, L-Glutamine Powder 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 Powder 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 what does it do in my body?
L-glutamine is an amino acid — a building block of protein — that your body naturally makes. It supports immune function, gut health, and muscle metabolism. This product delivers it as a supplement in powder form.
Will this help with my condition?
L-glutamine is proven effective for sickle cell disease. For HIV/AIDS-related wasting, recovery after surgery, and critical illness from trauma, it's possibly effective — meaning there's some evidence, but more research is needed. For other uses, effectiveness hasn't been established in our data.
What side effects should I watch for?
Most people experience mild digestive symptoms: belching, bloating, constipation, diarrhea, or nausea. Headache and muscle pain have also been reported. Symptoms tend to be manageable, and in rare cases where dizziness occurred, lowering the dose resolved it.
Is it safe to take while pregnant or breastfeeding?
L-glutamine is rated likely safe in pregnancy. For breastfeeding, there isn't enough reliable safety data — talk with your doctor or pharmacist to decide whether to use it while nursing.
Can I take this if I have kidney or liver disease?
Only under medical supervision. People with kidney or liver problems need to discuss this supplement with their doctor or pharmacist first, since glutamine metabolism is affected by these organs.
I have bipolar disorder — is this safe for me?
A small number of people with bipolar disorder reported mood changes (mania or hypomania) while taking glutamine. Talk with your clinician before starting this supplement.

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.

L-Glutamine Powder label
Go deeper

The Full Monographs Behind L-Glutamine Powder’s Ingredients

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

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

L-Glutamine Powder'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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