Oral supplementation studies
- Reported quantity
- 1–4 g per day, most commonly 2 g
- Frequency
- One to two divided administrations
- Study duration
- 4–24 weeks
Oral absorption saturates, which is why higher figures do not scale linearly in plasma.
Protocols · Metabolic
L-Carnitine: literature-reported ranges
L-carnitine is a well-studied nutrient cofactor with a large clinical literature in dialysis, cardiac and exercise-physiology settings. Its figures are unusually well established compared with most compounds in this section.
Read this first
Every figure on this page is a range reported in published literature or in a publicly documented study protocol. It is a record of what researchers used, not a recommendation, a therapeutic protocol, or advice. Peptide Intel Hub is an independent publication, sells nothing, and describes these compounds as in-vitro research reagents only.
Compound at a glance
- Class
- Quaternary ammonium compound (fatty-acid transport cofactor)
- Reported half-life
- Approximately 15 hours orally; shorter for the injectable form
- Routes used in the literature
- Oral, intravenous and intramuscular in the clinical literature
- Also written as
- —
What the published studies reported
Each row below describes one body of work. The model and population are part of the figure — a rodent per-kilogram quantity and a human trial quantity are not comparable.
Intravenous use in dialysis research
- Reported quantity
- 10–20 mg/kg
- Frequency
- After each dialysis session
- Study duration
- Months
This is the best-characterised parenteral figure in the literature.
Dosage chart
These figures match the published chart for this compound on peptidedosages.com, including the reconstitution volume, resulting concentration, insulin-syringe units and the staged schedule. Educational reference only — not instructions, and not medical advice.
L-Carnitine · 200 mg Vial
L-Carnitine is dosed at 50 mg–100 mg daily via subcutaneous injection in educational protocols. A 200 mg vial reconstituted with bacteriostatic water yields about 100 mg/mL. This information is for research and educational use only.
- Reconstitute
- Add 2.0 mL bacteriostatic water → 100 mg/mL concentration (1 unit = 1 mg).
- Typical daily range
- 50–100 mg once daily (gradual titration); advanced protocols may use up to 200 mg.
- Easy measuring
- At 100 mg/mL, 1 unit = 0.01 mL = 1 mg on a U-100 insulin syringe.
- Storage
- Lyophilized: freeze at −20 °C (−4 °F); after reconstitution, refrigerate at 2–8 °C (35.6–46.4 °F) and use within 2–4 weeks; do not freeze reconstituted solution.
Standard / Gradual Approach (2.0 mL = 100 mg/mL)
| Week | Daily Dose | Units (per injection) (mL) |
|---|---|---|
| Weeks 1–2 | 50 mg | 50 units (0.50 mL) |
| Weeks 3–8 | 100 mg | 100 units (1.0 mL) |
| Weeks 9–12 | 100 mg | 100 units (1.0 mL) |
Reconstitution maths
Injectable presentations arrive as a ready-made solution, commonly 200 mg/mL, rather than a lyophilised powder.
Open the reconstitution calculatorHow to read these figures
- Oral carnitine is metabolised by gut bacteria to TMAO, which has its own cardiovascular literature worth reading.
- L-carnitine and acetyl-L-carnitine have different tissue distribution and are not interchangeable.
- It is on the WADA monitoring list for high-volume intravenous use.
Sources and citations
These are the published records the figures on this page are drawn from. Each one describes what researchers administered, in which model or population, and over what period. Quantities reported in a study are specific to that study's design and are not transferable guidance.
- [1]L-Carnitine Supplementation for the Management of Fatigue in Patients With Cancer: An Eastern Cooperative Oncology Group Phase III, Randomized, Double-Blind, Placebo-Controlled Trial
Cruciani RA, Dvorkin E, Homel P, et al. · J Clin Oncol · 2012 · PMCID PMC3478577
Cancer patients with fatigue received oral L-carnitine 2 g/day (as levocarnitine, in divided doses) or placebo for 4 weeks in a randomized phase III trial.
View the record - [2]L-carnitine supplementation for the management of fatigue in patients with hypothyroidism on levothyroxine treatment: a randomized, double-blind, placebo-controlled trial
Malek Mahdavi A, Mahdavi R, Kolahi S. · Endocr J · 2016 · EJ16-0109
Hypothyroid patients on levothyroxine were given 1000 mg/day oral L-carnitine for 12 weeks to assess effects on fatigue.
View the record - [3]Progression of atherosclerosis with carnitine supplementation: a randomized controlled trial in the metabolic syndrome
Askarpour M, Hadi A, Miraghajani M, et al. · (RCT, metabolic syndrome) · 2022 · PMID 35366920
Patients with metabolic syndrome received oral carnitine supplementation over months, with carotid atherosclerosis progression as outcome, establishing a chronic dosing regimen.
View the record
Search the databases yourself
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All research protocolsPeptide Intel Hub is an independent publication and has no affiliation, ownership or commercial relationship with the suppliers listed. We sell nothing and take no payments — links are editorial references only.