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Dietary supplement

L-Glutamine 500 mg Ingredients & Drug Interactions

by NOW

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

L-Glutamine 500 mg is a dietary supplement by NOW 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 500 mg by NOW

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 produces. It's the form of glutamine used in clinical trials and supplements.

The capsule also contains inactive ingredients—hypromellose (a capsule material), rice flour, and ascorbyl palmitate (a form of vitamin C used as a preservative).

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: Immune function support and nitrogen transport.
  • We looked for evidence on: Postoperative infection, Postoperative recovery, Critical illness (trauma), HIV/AIDS-related wasting, Malnutrition, Oral mucositis — and 4 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), Postoperative recovery.
  • Also on file: Glutamine is rated "Possibly Ineffective" for Radiation-induced diarrhea.

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

These ratings come from clinical trial data, though the evidence for the "possibly effective" uses is still being built.

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 belching, bloating, constipation, diarrhea, flatulence, nausea, vomiting, headache, and gastrointestinal pain.

People with kidney or liver disease should take it only under medical supervision. There isn't enough safety data in pregnancy and breastfeeding to know whether supplemental doses are safe; talk with your doctor or pharmacist for personalized advice before using it in these situations.

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), talk to your pharmacist before starting this product. Glutamine is theoretically metabolized in a way that could reduce how well seizure medications work, though this hasn't been reported in real patients yet.

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 be worth considering if you have sickle cell disease or certain recovery scenarios—especially under medical guidance. If you take seizure medications, check with your pharmacist first.

People with kidney or liver disease should get medical supervision before starting. Your pharmacist can review your exact medications and medical history.

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, 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 500 mg, straight from the product label.

Brand NOW
Barcode (UPC) 733739000927
Net contents 120 Veg Capsule(s)
Market status On market
Date entered into DSLD Jul 25, 2024
DSLD ID 314417
Product type Amino Acid/protein
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Kosher, Halal, 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 500 mg by NOW, 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 Veg Capsule(s)
Maximum serving Sizes:
1 Veg Capsule(s)
Servings per container
120
UPC/BARCODE
733739000927
IngredientAmount% DV
L-Glutamine500 mg--

Other ingredients: Hypromellose, Rice Flour, Ascorbyl Palmitate

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: Take 1 capsule 1 to 3 times daily, preferably between meals.

Formula

Glutamine is considered to be a conditionally essential amino acid, which means that under certain circumstances, the body may require more Glutamine than it can produce. In the body, Glutamine functions as a major nitrogen transporter and is critical for the maintenance of healthy nitrogen balance. Glutamine also acts as the primary fuel for the rapidly growing cells of the immune system and GI tract.

Amino Acid

Triangle K (Kosher)

Crescent H (Halal)

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.

Precautions

Caution: For adults only. Keep out of reach of children.

Consult physician if pregnant/nursing, taking medication, or have a medical condition.

Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish, tree nut or sesame ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.

Formulation

Supports immune function Nitrogen transporter

Non-GMO

Vegetarian/Vegan

Made and quality tested in the USA with globally sourced ingredients. Natural color variation may occur in this product.

Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish, tree nut or sesame ingredients.

FDA Statement of Identity

A Dietary Supplement

Seals/Symbols

Triangle K (Kosher)

Crescent H (Halal) GMP Quality Assured

General Statements

Amino Acids Family owned since 1968.

Storage

Store in a cool, dry place after opening.

See for yourself

L-Glutamine 500 mg by NOW label

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

What’s inside

The Ingredients in L-Glutamine 500 mg by NOW

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

Serving size1 Veg Capsule(s) Dosage formCapsule Servings per container120 Amounts shown are per serving.

L-Glutamine

Interacts with
50 drugs
500 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: Hypromellose, Rice Flour, Ascorbyl Palmitate. These complete the product’s ingredient list but are not active constituents.

Interaction report

L-Glutamine 500 mg by NOW Drug Interactions

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 checker
50Drugs
50 Moderate

Ingredients driving the most interactions

Each 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-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 500 mg, from the product label.

NOW

See all NOW products
Name
NOW FOODS
Street Address
395 S. Glen Ellyn Rd.
City
Bloomingdale
State
IL
ZipCode
60108
Web Address
nowfoods.com
Pharmacist Counseling Corner

L-Glutamine 500 mg by NOW: Common Questions

Does L-Glutamine 500 mg by NOW interact with any medications?
Yes. Based on its ingredients, L-Glutamine 500 mg 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 500 mg 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 to take while pregnant or breastfeeding?
The safety data on supplemental L-glutamine in pregnancy and breastfeeding isn't established enough to say yes or no. Talk with your doctor or pharmacist before using it in these situations—they can give you personalized advice based on your health.
What are the most common side effects?
Belching, bloating, constipation, diarrhea, flatulence, nausea, vomiting, and headache are the side effects seen in trials. Gastrointestinal pain has also been reported. These tend to happen with higher doses—one patient's dizziness resolved when the dose was cut in half.
Can I take this if I have kidney or liver disease?
You shouldn't take supplemental L-glutamine without medical supervision if you have kidney or liver disease. Talk to your doctor first, since they'll want to monitor you.
What does L-glutamine actually do in the body?
L-glutamine is an amino acid your body makes naturally. It's involved in immune function, gut health, and muscle recovery. This product is meant to provide extra glutamine for conditions like sickle cell disease or recovery from surgery or critical illness.
Does this product have fillers?
The capsule contains hypromellose (the capsule material itself), rice flour, and ascorbyl palmitate (a preservative). These are standard inactive ingredients in supplements.

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

Not sure if L-Glutamine 500 mg 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 500 mg label
Go deeper

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

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.

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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