L-Carnitine

Lyophilized powder

L-carnitine is an amino-acid-derived compound that carries long-chain fatty acids into mitochondria to be used for energy; the body makes it and also gets it from food. It is not a peptide. Below: today's vial sizes, prices through our link and the vendor's COA details.

Size

$0.01/mg · In stock

Price

$34.00

List

$40.00

Buy 5000 mg at Ion Peptide

Price shown uses code thepeptidecatalog at Ion Peptide's checkout (15% off list).

Volume pricing at Ion Peptide

  • 4+ vials10% off$30.00/ea
  • 6+ vials16% off$27.60/ea
  • 10+ vials25% off$24.00/ea

Applied in Ion Peptide's cart; per-vial figures include our code.

Sold by Ion Peptide. The Peptide Catalog does not sell peptides; we earn a commission if you buy through this link, at no extra cost to you. For laboratory research use only, not for human or veterinary use. Not FDA-approved. Nothing on this page is medical or dosing advice.

L-Carnitine research vial
L-CarnitineIon Peptide
Third-party testedResearch use only
Certificate of AnalysisVendor-stated: Third-party tested · HPLC + MS · COA per productView
  • Vendor-stated testing: Third-party tested · HPLC + MS · COA per product
  • Listed on our l-carnitine vendor comparison, ordered by our vendor rankings
  • Lyophilized powder · laboratory research use only
Research-context information only. L-Carnitine is a naturally occurring amino-acid derivative, not a peptide. Protocols, doses, and reactions reported below come from published research and self-reported community sources. This article reports what has been documented, not what should be done. Consult a licensed physician for personal medical decisions.

Vial sizes listed by the vendor

L-Carnitine Vial Sizes & Prices

L-Carnitine vial sizes, prices and lots at Ion Peptide
SizeListWith our codePer mgAvailability
5000 mg$40.00$34.00$0.01In stock

Prices checked today, 5:17 AM CT on Ion Peptide's site, with code thepeptidecatalog applied. Vendor-stated testing: Third-party tested · HPLC + MS · COA per product. The lot certificate is on Ion Peptide's product page. Sizes not re-checked in the last 7 days are hidden. The vendor's checkout is final.

Test results

L-Carnitine Certificate of Analysis

Ion Peptide posts the certificate on each product page (vendor-stated: Third-party tested · HPLC + MS · COA per product). Match the lot number on the vial to its certificate.

View the L-Carnitine certificate on Ion Peptide's product page.

How to check one: how to verify a peptide COA.

L-Carnitine Dosing in Clinical Research

Fat Metabolism / Recovery / Energy (Extensive Human Data)

Educational reference only. Individual responses vary. Consult healthcare provider before use.

Vial Size
500 mg/mL injectable solution (10 mL)
Reconstitution
Injectable forms ship as a ready solution; oral forms also available
Dose
500-2000 mg per day — common research/clinical range
Timing
Pre-workout or with meals
Frequency
Daily; injectable bypasses low (~15%) oral bioavailability
Duration
Ongoing; benefits build over weeks
Protocol Notes
Amino-acid-derived compound central to the carnitine shuttle (fatty-acid transport into mitochondria). Common doses are 500-2000 mg/day; injectable 500 mg/mL forms bypass the low ~15% oral bioavailability. Forms: L-carnitine (base), acetyl-L-carnitine/ALCAR (crosses the blood-brain barrier for cognition), L-carnitine L-tartrate/LCLT (exercise recovery). Fat-loss effect is modest and strongest in deficient or older people. Note the debated gut-to-TMAO cardiovascular question. Generally well tolerated; high oral doses cause GI upset and fishy odor. Sold for research purposes only.

Why This Dosing Protocol

What dose? Research and clinical use commonly runs 500-2000 mg/day. Injectable 500 mg/mL forms bypass the low ~15% oral bioavailability.

Which form? ALCAR (acetyl) for cognition (crosses the blood-brain barrier), L-carnitine L-tartrate (LCLT) for exercise recovery, plain L-carnitine for general energy and fat metabolism.
Full Dosing GuideReconstitution Calculator

How L-Carnitine Works

Amino-Acid-Derived Mitochondrial Transporter — Fat Metabolism / Recovery (Extensive Human Data)

Target → Signal → Effect → Outcomes

1
Target

The Carnitine Shuttle (CPT-I / CPT-II)

L-Carnitine is the substrate of the carnitine shuttle — carnitine palmitoyltransferase I and II — which carries long-chain fatty acids across the inner mitochondrial membrane. Without it, those fats cannot enter the mitochondria to be burned.

2
Cellular Signal

Fatty-Acid Beta-Oxidation for Energy

Once inside the mitochondria, the transported fatty acids undergo beta-oxidation to produce ATP. Adequate carnitine supports fat-derived energy and buffers the acyl-CoA pool, which is part of why it is studied for fatigue and exercise recovery.

3
Systemic Effect

Energy, Recovery, and Modest Fat Metabolism

The strongest, most consistent effects are in deficiency correction, exercise recovery (less muscle damage and soreness with L-carnitine L-tartrate), and fatigue reduction. The fat-loss effect is modest and most evident in deficient or older people. ALCAR, the acetyl form, crosses the blood-brain barrier for cognition/mood.

4
What You Notice

Builds Over Weeks; Recovery Before Fat Loss

Because oral bioavailability is low (~15%) and tissue stores build slowly, effects accrue over weeks rather than acutely. Recovery and energy benefits tend to show before any body-composition change. Injectable forms bypass the low oral absorption.

What Makes This Peptide Different

Unlike most compounds here, L-Carnitine is an endogenous nutrient with a very large human evidence base and an FDA-approved use (carnitine deficiency). The honest framing is recovery/energy support rather than a powerful fat-burner — and the gut-to-TMAO metabolism is a genuine, debated cardiovascular caveat.

Technical specifications

L-Carnitine chemical & analytical data

Form
Solution in a sealed vial
Presentation
5000 mg
Regulatory status
Amino-acid derivative (not a peptide); research-grade vials are not FDA-approved.

L-Carnitine Reconstitution Calculator

Dilution math and unit conversions. Prefilled using a common vial size for this peptide.

Open calculator

Storage & Handling

Storage at a glance

Proper storage temperatures, shelf life, reconstitution best practices, and travel tips for lyophilized and reconstituted peptides.

Powder: Freezer
1+ year at -20°C
Reconstituted: Fridge
4 weeks max at 2-8°C
View Complete Storage Guide

Handling specifics

Educational overview on storage, labeling, and traceability considerations for lab environments. Consult primary literature and vendor documentation for specifics.

Powder storage (very stable)
  • Freezer (-20°C): 1+ year
  • Refrigerator (2-8°C): 1-3 months
  • Room temperature: 2-3 weeks (emergency only)
Reconstituted storage (fragile)
  • MUST refrigerate at 2-8°C
  • 4-week maximum shelf life
  • NEVER freeze after reconstitution
  • Use bacteriostatic water for multi-dose

7 answers

L-Carnitine FAQ: Buying, COA, Storage & Research

What is L-Carnitine?
L-Carnitine is an amino-acid-derived compound the body makes from lysine and methionine. Its central job is the carnitine shuttle — transporting long-chain fatty acids across the inner mitochondrial membrane so they can be burned for energy. It is studied for fat metabolism, exercise recovery, and fatigue, with a large human evidence base.
Does L-Carnitine actually burn fat?
The effect is real but modest, and strongest in people who are deficient or older. In healthy young people it is not a powerful standalone fat-burner. Oral bioavailability is low (~15%), which is why injectable or higher doses are sometimes used. It is better framed as recovery/energy support than as a fat-loss drug.
L-Carnitine vs acetyl-L-carnitine (ALCAR)?
ALCAR is the acetylated form that crosses the blood-brain barrier, so it is the variant studied for cognition and mood. Plain L-carnitine and L-carnitine L-tartrate (LCLT) are used more for energy, fat metabolism, and exercise recovery. They share the same core mechanism but differ in where they act.
Is the TMAO heart-risk concern real?
It's a genuine but debated question. Gut bacteria metabolize carnitine into TMA, which the liver converts to TMAO — a metabolite that observational studies have linked to atherosclerosis and cardiovascular risk. The link is associative and contested, not proven cause-and-effect, but it is worth knowing when weighing long-term use.
How long does reconstituted peptide last?
Once mixed with bacteriostatic water, peptides remain stable for up to 4 weeks when refrigerated at 2-8°C (36-46°F). Unopened powder can last 1+ year in the freezer. Get our complete Storage & Travel Guide.
Is this peptide legal to purchase?
Peptides sold "for research purposes only" are legal to purchase in the US, but are not FDA-approved for human use outside of specific medical applications. Always consult a healthcare provider before use.
New to peptides?
Take our Peptide Match tool to find the best peptide for your goals. You can also read our Complete Guide to Peptides to learn the basics.

L-Carnitine Research Articles

dosing

L-Carnitine Dosage: 500-2000 mg Protocols

Why oral L-carnitine is only ~15% absorbed, how injectable 500 mg/mL forms bypass that, and the 500-2000 mg/day ranges used across the clinical literature.

side-effects

L-Carnitine Side Effects: What's Real

L-carnitine is well tolerated — but GI upset, a fishy body odor, and a debated TMAO–heart-risk signal are worth understanding before you buy.

results

L-Carnitine Results Timeline: What to Expect

L-carnitine works on muscle stores, not blood levels — which is why recovery and fatigue effects take weeks, not days. Here's the documented timeline.

buying-guide

Buy L-Carnitine: Compare 2 Vendors, From $40

Compare 2 L-Carnitine vendors side by side: from $40 a vial, best value $0.01/mg. Codes save up to 15%. Vial sizes, COA status, real cost per week.

Compare L-Carnitine Vendors Before You Buy

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