L-Carnitine

Metabolic & weight FDA-approved drug

Amino-acid-derived mitochondrial fatty-acid transport cofactor · also known as Levocarnitine, Carnitor

For reference only — not medical advice. Figures are commonly reported values compiled from published sources and may be wrong or out of date. Many compounds listed are not approved for human use. Talk to a licensed clinician before using any compound.

Carnitine is made in the body and obtained from food, and levocarnitine is its biologically active form. It is FDA-approved as a prescription medicine for carnitine deficiency, including in people on dialysis, and is also widely sold as an oral supplement. Injectable use for fat-loss purposes appears in community charts but is not a labeled use.

Commonly reported dosing (200 mg vial)

Reconstituted with 2 mL → 100 mg/mL.

Phase	Dose	Volume	U-100 units
Starting	50 mg	0.5 mL	50
Standard	100 mg	1 mL	100

Frequency: Once daily, subcutaneous (community-reported) · Half-life: About 17 hours terminal half-life after intravenous dosing (prescribing information)

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Commonly reported dose escalation

Weeks	Dose	Volume	U-100 units
Weeks 1-2	50 mg	0.5 mL	50
Week 3+	100 mg	1 mL	100

Higher steps may need a larger vial or more than one draw. Escalation schedules vary; dosing decisions belong to a licensed clinician.

Commonly reported reconstitution steps

Vials are usually brought to room temperature (about 15-20 minutes) first.
2 mL of bacteriostatic water is added slowly down the inside wall of the 200 mg vial.
The vial is swirled gently until clear, not shaken.
This gives 100 mg/mL. Mixed vials are typically labeled with the date and refrigerated.

Storage

Before mixing: Lyophilized vials are commonly stored frozen (around -20 °C) and protected from light.

After mixing: Reconstituted solution is commonly kept refrigerated (2-8 °C), protected from light, and not frozen. Bacteriostatic water does not set a universal use-by period, so product-specific handling guidance is followed.

How it works

Carnitine acts as a carrier that moves activated long-chain fats into the mitochondrial matrix for oxidation, and it also helps buffer and clear excess acyl groups.

Researched for

Approved use in primary and secondary carnitine deficiency, and in carnitine loss during dialysis.
Studied in many small trials for exercise performance, fatigue and metabolic outcomes, with mixed results.

Notes

The FDA-approved injection (Carnitor) is labeled for intravenous use only. The subcutaneous schedule here is a community-reported chart, not label guidance.
A 200 mg vial reconstituted to 2 mL gives 100 mg/mL, so 100 mg is 1 mL.
Reported side effects in the prescribing information include injection-site reactions, headache and transient nausea and vomiting.