L-Carnosine 500 mg Ingredients & Drug Interactions
by NOW
What is this page for?
First and foremost: checking L-Carnosine 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-Carnosine 500 mg is a dietary supplement by NOW with 1 active ingredient. Its ingredients are commonly taken for anti-aging and general wellness, exercise performance and muscle support, brain and cognitive health.Based on those ingredients, 86 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are L-Carnosine. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.
Check Your Meds Against L-Carnosine 500 mg by NOW
Ask about any prescription or over-the-counter medication and we check it for interactions with L-Carnosine 500 mg by NOW — 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-Carnosine 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.
What’s inside
Full disclosure
This product has one active ingredient: L-Carnosine, a compound made naturally in your body that plays a role in muscle function and cellular health. The capsule also contains inactive ingredients — hypromellose, stearic acid, and silicon dioxide — which help hold the supplement together and have no active effect.
Does it work?
Not established
The evidence for L-Carnosine is thin. It's rated possibly ineffective for autism spectrum disorder.
For age-related cognitive decline, Alzheimer's disease, athletic performance, cataracts, and cognitive impairment, we don't have enough reliable evidence to rate whether it works. If you're considering it for one of these reasons, talk with your pharmacist or doctor about what the current research actually supports.
How safe is it?
Well-documented data
L-Carnosine is generally well tolerated in short-term studies, but long-term safety data are limited, so we don't have a clear picture of what happens if you take it for months or years. Some people report decreased appetite, dry mouth, small weight changes, foot and joint pain, or rarely pneumonia.
There isn't enough safety information to use carnosine during pregnancy or while breastfeeding — the facts advise against it in both cases.
Meds to double-check
Moderate interaction found
If you take any antidiabetes drugs or medications to manage blood sugar, check your specific medicines with the search tool before taking this product — carnosine may increase the risk of low blood sugar (Moderate severity).
The bottom line
Scorecard at a glanceFully disclosed formula with no established evidence rating for its marketed use. Moderate medication interactions have been identified, and safety information is well characterized.
L-Carnosine is a single-ingredient supplement with limited evidence for the conditions it's often used for. If you take diabetes medication, you'll need to check with your pharmacist before starting it, since it may lower blood sugar further.
For pregnancy, breastfeeding, or long-term use, talk to your doctor or pharmacist first.
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 Sep 25, 2025.
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-Carnosine 500 mg, straight from the product label.
| Brand | NOW |
|---|---|
| Barcode (UPC) | 733739000781 |
| Net contents | 50 Veg Capsule(s) |
| Market status | On market |
| Date entered into DSLD | Sep 25, 2025 |
| DSLD ID | 335262 |
| Product type | Non-nutrient/non-botanical |
| Supplement form | Capsule |
| Dietary claims / uses | All Other, Structure/Function |
| Intended target group(s) | Vegan, Vegetarian, Adult (18 - 50 Years), Kosher, Gluten Free, Dairy Free |
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-Carnosine 500 mg by NOW, sourced from the NIH Dietary Supplement Label Database.
Supplement Facts
| Ingredient | Amount | % DV |
|---|---|---|
| L-Carnosine | 500 mg | -- |
Other ingredients: Hypromellose, Stearic Acid, Silicon Dioxide
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
Suggested Usage: Take 1 capsule 1 to 3 times daily, preferably with food.
Formula
Carnosine (beta-alanyl-L-histidine) is a dipeptide, consisting of alanine and histidine. It is naturally found in high concentrations in muscles and nerve tissues and its levels are known to decrease with age. Carnosine protects cell and tissue structures during the aging process through its free-radical neutralizing and membrane-stabilizing functions.
Triangle K (Kosher)
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, corn, milk, egg, fish, shellfish, tree nut, or sesame ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.
General Statements
This bottle is made from 100% PCR (post-consumer recycled) resin.
Amino acids Family owned since 1968.
Formulation
Healthy aging Supports muscle vitality Free radical scavenger Supports cell integrity
Non-GMO
Vegetarian/Vegan
Packaged and quality tested in the USA.
Not manufactured with wheat, gluten, soy, corn, milk, egg, fish, shellfish, tree nut, or sesame ingredients.
Natural color variation may occur in this product.
FDA Statement of Identity
A Dietary Supplement
Seals/Symbols
Triangle K (Kosher)
GMP Quality Assured
Storage
Store in a cool, dry place after opening.
Is this label outdated? Report a formula or label change and our pharmacy team will review it.
L-Carnosine 500 mg by NOW 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-Carnosine 500 mg by NOW
This is the 1 active ingredient this product is made of. Select it to open its full monograph.
Serving size1 Capsule(s) Dosage formCapsule Servings per container50 Amounts shown are per serving.
L-Carnosine
Interacts with86 drugs
Carnosine is a naturally occurring dipeptide (made of beta-alanine and histidine) that acts as an antioxidant and buffer in muscle and brain. It is so...
L-Carnosine monograph & interactionsOther (inactive) ingredients: Hypromellose, Stearic Acid, Silicon Dioxide. These complete the product’s ingredient list but are not active constituents.
L-Carnosine 500 mg by NOW Drug Interactions
HelloPharmacist Interaction Report
NOW's L-Carnosine 500 mg contains a single active ingredient that does interact with medications.
L-Carnosine may increase the risk of low blood sugar (hypoglycemia) if you take it alongside antidiabetes drugs — this is a Moderate-severity concern. Some early research suggests carnosine might lower fasting blood sugar on its own, which combined with diabetes medication could tip your levels too low.
Read the full breakdown — every affected drug type, severity by severity
Altogether, these interactions span 85 individual medications. If you take any drug to manage blood sugar or diabetes, check your exact medications with the tool on this page before starting carnosine.
Check your own medications below · Editorial policy · How we use AI
Want to check YOUR meds against L-Carnosine 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-Carnosine 500 mg interact with 86 drugs. Click any drug to see the details.
1 of the 1 ingredient in L-Carnosine 500 mg interact with drugs. Each result below shows which ingredient is responsible. L-Carnosine
GlucoseIV Glucose
How Glucose interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Glucose interactionGlyburideAlbert Glyburide, Diabeta, Glycron, Glynase, Glynase PresTab, Micronase +1 more
How Glyburide interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Glyburide interactionGlyburide, MetforminGlucovance
How Glyburide, Metformin interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Glyburide, Metformin interactionInhaled InsulinExubera
How Inhaled Insulin interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Inhaled Insulin interactionInsulinNovoRapid Insulin
How Insulin interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin interactionInsulin (bovine)Hypurin Bovine Neutral
How Insulin (bovine) interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin (bovine) interactionInsulin (human)Afrezza, Novolin 70/30, Novolin L, Novolin N, Novolin R
How Insulin (human) interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin (human) interactionInsulin (pork)Hypurin Porcine Neutral, Lente Iletin II, NPH Iletin, NPH Iletin II, Pork Actrapid, Regular Iletin +1 more
How Insulin (pork) interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin (pork) interactionInsulin (rdna)Actrapid, Humalog, Humalog Mix 75/25, Humulin 50/50, Humulin 70/30, Humulin L +8 more
How Insulin (rdna) interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin (rdna) interactionInsulin AspartFiasp
How Insulin Aspart interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Aspart interactionInsulin Aspart, Insulin DegludecRyzodeg 70/30
How Insulin Aspart, Insulin Degludec interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Aspart, Insulin Degludec interactionInsulin DegludecTresiba
How Insulin Degludec interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Degludec interactionInsulin Degludec, LiraglutideXultophy 100/3.6
How Insulin Degludec, Liraglutide interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Degludec, Liraglutide interactionInsulin GlargineBasaglar, Lusduna, Semglee
How Insulin Glargine interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Glargine interactionInsulin Glargine (rdna)Lantus
How Insulin Glargine (rdna) interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Glargine (rdna) interactionInsulin Glargine RecombinantToujeo Solostar
How Insulin Glargine Recombinant interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Glargine Recombinant interactionInsulin Glargine, LixisenatideSoliqua 100/33
How Insulin Glargine, Lixisenatide interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Glargine, Lixisenatide interactionInsulin Glulisine (rdna)Apidra
How Insulin Glulisine (rdna) interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Glulisine (rdna) interactionInsulin Human, Sodium ChlorideMyxredlin
How Insulin Human, Sodium Chloride interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Human, Sodium Chloride interactionInsulin LisproAdmelog, Admelog Solostar
How Insulin Lispro interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Lispro interactionInsulin Lispro RecombinantHumalog Kwikpen
How Insulin Lispro Recombinant interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Lispro Recombinant interactionInsulin Lispro-aabcLyumjev
How Insulin Lispro-aabc interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Lispro-aabc interactionInsulin DetermirLevemir
How Insulin Determir interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Insulin Determir interactionLinagliptinTradjenta
How Linagliptin interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Linagliptin interactionLinagliptin, Metformin HydrochlorideJentadueto XR
How Linagliptin, Metformin Hydrochloride interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Linagliptin, Metformin Hydrochloride interactionLiraglutideVictoza
How Liraglutide interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Liraglutide interactionLiraglutide RecombinantSaxenda
How Liraglutide Recombinant interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Liraglutide Recombinant interactionLixisenatideAdlyxin
How Lixisenatide interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Lixisenatide interactionMetforminGlucophage, Metformin
How Metformin interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Metformin interactionMetformin HydrochlorideRiomet ER
How Metformin Hydrochloride interacts with L-Carnosine 500 mg — through 1 ingredient. Tap an ingredient for the detail:
L-carnosineAntidiabetes Drugs Moderate
Interaction Summary
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Read the full L-carnosine + Metformin Hydrochloride interactionEach ingredient & the kinds of drugs it affects
For each ingredient in L-Carnosine 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-Carnosine
Antidiabetes Drugs
Theoretically, taking carnosine with antidiabetes drugs might increase the risk of hypoglycemia.
Some, but not all, preliminary clinical research shows that carnosine might reduce fasting blood glucose levels.
Brand information
Manufacturer and brand details for L-Carnosine 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
L-Carnosine 500 mg by NOW: Common Questions
Does L-Carnosine 500 mg by NOW interact with any medications?
How can one product interact with so many drugs?
Where does this information come from?
Can I take L-Carnosine if I'm pregnant or breastfeeding?
Does L-Carnosine actually work for cognitive decline or Alzheimer's?
What side effects should I watch for?
Is L-Carnosine safe to take long-term?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Not sure if L-Carnosine 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-Carnosine 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-Carnosine 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 5 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.
Carnosine 5 references
- Chengappa KN, Turkin SR, DeSanti S, et al. A preliminary, randomized, double-blind, placebo-controlled trial of L-carnosine to improve cognition in schizophrenia. Schizophr Res 2012;142(1-3):145-52. PubMed
- Karkabounas S, Papadopoulos N, Anastasiadou C, et al. Effects of a-lipoic Acid, carnosine, and thiamine supplementation in obese patients with type 2 diabetes mellitus: A randomized, double-blind study. J Med Food. 2018;21(12):1197-1203.
- Peng W, Mao P, Liu L, et al. Effect of carnosine supplementation on lipid profile, fasting blood glucose, HbA1C and insulin resistance: a systematic review and meta-analysis of long-term randomized controlled trials. Complement Ther Med 2020;48:102241. PubMed
- Siriwattanasit N, Satirapoj B, Supasyndh O. Effect of oral carnosine supplementation on urinary TGF-ß in diabetic nephropathy: a randomized controlled trial. BMC Nephrol 2021;22(1):236. PubMed
- Sureshkumar K, Durairaj M, Srinivasan K, et al. Effect of L-Carnosine in Patients with Age-Related Diseases: A Systematic Review and Meta-Analysis. Front Biosci (Landmark Ed) 2023;28(1):18. 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