L-Carnitine (Injectable)
Amino acid derivative involved in fatty acid transport into mitochondria. Injectable form used in bodybuilding for fat metabolism, androgen receptor upregulation, and fertility support. Also available orally but with poor bioavailability.
Overview
Amino acid derivative involved in fatty acid transport into mitochondria. Injectable form used in bodybuilding for fat metabolism, androgen receptor upregulation, and fertility support. Also available orally but with poor bioavailability.
Enhances fatty acid oxidation, may upregulate androgen receptor density, improves sperm quality and motility, supports insulin sensitivity, no significant impact on standard blood panels, mild injection site irritation possible
Compound Guide
Mechanism: L-Carnitine shuttles long-chain fatty acids across the inner mitochondrial membrane for beta-oxidation. Injectable form bypasses poor oral bioavailability (~15-20% oral vs ~100% injectable). Also acts as an antioxidant and may increase androgen receptor density in muscle tissue.
Dosage:
- Injectable (intramuscular): 200-600mg per injection, 2-5x/week
- Oral (L-Carnitine L-Tartrate): 2000-3000mg/day (much lower bioavailability)
Administration:
- Intramuscular injection, typically into the muscle being trained or glutes/delts
- Can cause a mild burning sensation at the injection site — inject slowly
- Some users split into multiple smaller injections per day
Key Notes:
- Primary bodybuilding uses: fat metabolism support, androgen receptor upregulation, fertility/sperm quality
- Androgen receptor upregulation theory: may increase the density of androgen receptors in muscle, potentially enhancing the effect of testosterone and other androgens
- Fertility: well-documented improvements in sperm motility, morphology, and concentration — commonly used in PCT/recovery
- Injectable form is strongly preferred over oral due to dramatically better bioavailability
- Very safe compound — no significant impact on liver, kidney, or hormonal panels
- May provide mild cardiovascular benefit through improved fatty acid metabolism
- Often used alongside TRT/HRT and fertility protocols
- Monitor: no specific blood markers required; lipid panel and fertility markers if relevant
Usage History
Markers to Monitor
Frequently Asked Questions
Quick Reference
Category
Ancillary
Half-Life
~2-4 hours (injectable)
Detection Time
N/A