L-Carnitine
Also known as: ALCAR · Acetyl-L-Carnitine · Levocarnitine
An amino acid derivative essential for transporting fatty acids into mitochondria for energy production, supporting fat metabolism, exercise performance, and cognitive function.
Overview
L-Carnitine is a naturally occurring amino acid derivative synthesized from lysine and methionine that plays an essential role in energy metabolism by transporting long-chain fatty acids across the inner mitochondrial membrane for beta-oxidation. Without adequate carnitine, fatty acids cannot enter the mitochondria and are instead stored as body fat. Injectable L-Carnitine provides significantly higher bioavailability than oral forms (which have only ~15-20% absorption). In health optimization, L-Carnitine is used to enhance fat oxidation during exercise, improve recovery, support cardiovascular health, and boost cognitive function (particularly the acetyl-L-carnitine form, which crosses the blood-brain barrier).
It also improves insulin sensitivity by enhancing glucose oxidation and reducing lipotoxicity in muscle cells.
Mechanism of Action
Shuttles long-chain fatty acids across the inner mitochondrial membrane via the carnitine palmitoyltransferase (CPT) system. Acetyl-L-carnitine also donates acetyl groups to support acetylcholine synthesis and mitochondrial energy production. Reduces lipid accumulation in muscle and liver, improving insulin sensitivity.
Key Benefits
Potential Side Effects
Common Stacks
This peptide is commonly combined with the following compounds for synergistic effects:
Known Interactions
The following interactions have been documented for L-Carnitine. Always consult a healthcare professional before combining compounds.
Synergistic (5)
AOD-9604 mobilizes fatty acids while L-Carnitine shuttles them into mitochondria for oxidation. Complementary fat-burning mechanisms.
Cardarine activates PPARδ to enhance fat oxidation while L-Carnitine facilitates fatty acid transport into mitochondria. Strong fat-burning synergy.
BAM15 uncouples mitochondria to burn fat as heat while L-Carnitine shuttles fatty acids into mitochondria. Complementary fat oxidation mechanisms.
B12 supports methylation and energy metabolism while L-Carnitine enhances fat oxidation. Common energy and metabolism support stack.
Lipo-C (lipotropic blend) supports liver fat metabolism while L-Carnitine shuttles fatty acids into mitochondria. Complementary fat metabolism support.
Scientific References
Quick Reference
Typical Dose
300mg-1000mg
Frequency
1-2x daily pre-exercise
Route
Intramuscular or subcutaneous injection, or oral
Half-Life
~2-3 hours (injectable)
Cycle Length
Can be used continuously; daily or on workout days
FDA Status
FDA approved (Levocarnitine/Carnitor) for carnitine deficiency. Available as dietary supplement.
Need to calculate dosing?
Use our reconstitution calculator to determine exact syringe measurements.
Open CalculatorThis information is for educational purposes only. Consult a qualified healthcare professional before using any peptide. Dosing information reflects commonly reported protocols and may not be appropriate for everyone.
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