L-Carnitine
Carries fatty acids into mitochondria so they can be burned for energy. Injectable carnitine treats carnitine deficiency; weight-loss benefits are not well established.
Prescription injectable in the US (Carnitor) for carnitine deficiency; also a supplement.
Look it up on Wikipedia38 listings across 22 independently tested vendors, ranked by price per milligram after coupon codes anyone can use. Vendors you can only order from by message are hidden.
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FDA-approved as levocarnitine (Carnitor).
Daily price tracking started October 7, 2026; a price-history chart appears here once a few days have been collected.
| Vendor | Trust | Listing | Vials | Price | Per mg | |
|---|---|---|---|---|---|---|
Shanghai Wibson Biotechnology WBS #263 by metascore · China |
L-carnitine 5000mg/10ml*10vials (China warehouse) [jinjier] | 10 × 5000 mg = 50000 mg | $150.00 $15.00 per vial |
$0.003 | Buy | |
Shanghai Wibson Biotechnology WBS #263 by metascore · China |
L-Carnitine 5000mg*10vials (China warehouse) [wbspeptide.com] | 10 × 5000 mg = 50000 mg | $195.00 $19.50 per vial |
$0.004 | Buy | |
Amino Usa #136 by metascore · US |
Metascore 74 medium confidenceFinnrick 32%Bought vials 89% of label · 3 testsTitrateLabNo report for thisAccount needed |
L-Carnitine | 1 × 12000 mg | $55.00 | $0.005 | Buy |
Andy Peps Studio #64 by metascore · China |
LC1200 L-carnitine 1200mg * 10 vials | 10 × 1200 mg = 12000 mg | $65.00 $6.50 per vial |
$0.005 | Buy | |
Baohua Dongnuo Biotechnology BHD #77 by metascore · China |
LC1200 L-carnitine 1200mg * 10 vials | 10 × 1200 mg = 12000 mg | $65.00 $6.50 per vial |
$0.005 | Buy | |
LN Peptides #254 by metascore · China |
Metascore 71Finnrick 72%Bought vials 99% of label · 39 testsTitrateLabNo report for thisOnline checkout |
LC1200 L-carnitine 1200mg * 10 vials | 10 × 1200 mg = 12000 mg | $65.00 $6.50 per vial |
$0.005 | Buy |
BeiBangAn #28 by metascore · China |
LC1200 L-carnitine 1200mg * 10 vials | 10 × 1200 mg = 12000 mg | $65.00 $6.50 per vial |
$0.005 | Buy | |
Shanghai Wibson Biotechnology WBS #263 by metascore · China |
L-carnitine 2000mg/10ml*10vials (China warehouse) [jinjier] | 10 × 2000 mg = 20000 mg | $120.00 $12.00 per vial |
$0.006 | Buy | |
Shanghai Wibson Biotechnology WBS #263 by metascore · China |
L-Carnitine 2000mg*10vials (China warehouse) [wbspeptide.com] | 10 × 2000 mg = 20000 mg | $160.00 $16.00 per vial |
$0.008 | Buy | |
Hangzhou Youngpeptide Biotechnology HYB #153 by metascore |
L-carnitine 1200 mg – 10 Vials | 10 × 1200 mg = 12000 mg | $100.00 $10.00 per vial |
$0.008 | Buy | |
Andy Peps Studio #64 by metascore · China |
LC600 L-carnitine 600mg * 10 vials | 10 × 600 mg = 6000 mg | $55.00 $5.50 per vial |
$0.009 | Buy | |
Baohua Dongnuo Biotechnology BHD #77 by metascore · China |
LC600 L-carnitine 600mg * 10 vials | 10 × 600 mg = 6000 mg | $55.00 $5.50 per vial |
$0.009 | Buy | |
LN Peptides #254 by metascore · China |
Metascore 71Finnrick 72%Bought vials 99% of label · 39 testsTitrateLabNo report for thisOnline checkout |
LC600 L-carnitine 600mg * 10 vials | 10 × 600 mg = 6000 mg | $55.00 $5.50 per vial |
$0.009 | Buy |
BeiBangAn #28 by metascore · China |
LC600 L-carnitine 600mg * 10 vials | 10 × 600 mg = 6000 mg | $55.00 $5.50 per vial |
$0.009 | Buy | |
Simple Peptide #25 by metascore · US, FL 33446 |
Metascore 83Finnrick 62%PepIndex 82/100Bought vials 100% of label · 44 testsTitrateLabLab 97.8% pureOnline checkout |
L-Carnitine 5000MG | 1 × 5000 mg | $60.00 | $0.012 | Buy |
Hangzhou Youngpeptide Biotechnology HYB #153 by metascore |
L-carnitine 600 mg – 10 Vials | 10 × 600 mg = 6000 mg | $80.00 $8.00 per vial |
$0.013 | Buy | |
Gulf Coast Aminos #17 by metascore |
Metascore 85 medium confidenceFinnrick 81%Bought vials 109% of label · 3 testsTitrateLabNo report for thisAccount needed |
L-Carnitine 600mg/10ml | 1 × 600 mg | $24.95 | $0.042 | Buy |
Kits4less #80 by metascore · US |
Metascore 77 medium confidenceFinnrick 83%Bought vials 101% of label · 7 testsTitrateLab · PeptideCheckedNo report for thisOnline checkout |
L-Carnitine 600mg 20ml | 1 × 600 mg | $35.00 | $0.058 | Buy |
Ion Peptide #4 by metascore |
Metascore 87 medium confidenceFinnrick 82%Bought vials 108% of label · 4 testsTitrateLab · PeptideBase · Peptide CriticNo report for thisConfirmed with lab: 40 of 40Online checkout |
L-Carnitine – 500mg | 1 × 500 mg | $30.00 | $0.060 | Buy |
Go Alpha Labs Peptides #51 by metascore · US |
Metascore 80Finnrick 52%Bought vials 100% of label · 11 testsTitrateLabNo report for thisConfirmed with lab: 37 of 37Online checkout |
L-Carnitine (500mg) (10 Vials) | 10 × 500 mg = 5000 mg | $449.99 $45.00 per vial |
$0.090 | Buy |
Amino Asylum #245 by metascore |
Metascore 71Finnrick 62%PepIndex 26/100Bought vials 100% of label · 15 testsTitrateLab · PeptideBaseNo report for thisOnline checkout |
L-CARNITINE 200mg | 1 × 200 mg | $19.99 | $0.100 | Buy |
Amino Asylum #245 by metascore |
Metascore 71Finnrick 62%PepIndex 26/100Bought vials 100% of label · 15 testsTitrateLab · PeptideBaseNo report for thisOnline checkout |
L-CARNITINE 400mg | 1 × 400 mg | $39.99 | $0.100 | Buy |
Amino Asylum #245 by metascore |
Metascore 71Finnrick 62%PepIndex 26/100Bought vials 100% of label · 15 testsTitrateLab · PeptideBaseNo report for thisOnline checkout |
L-CARNITINE 600mg | 1 × 600 mg | $59.99 | $0.100 | Buy |
Go Alpha Labs Peptides #51 by metascore · US |
Metascore 80Finnrick 52%Bought vials 100% of label · 11 testsTitrateLabNo report for thisConfirmed with lab: 37 of 37Online checkout |
L-Carnitine (500mg) | 1 × 500 mg | $59.99 | $0.120 | Buy |
Chimera Peptides #19 by metascore |
Metascore 84Finnrick 87%Bought vials 101% of label · 27 testsTitrateLab · Peptide CriticNo report for thisOnline checkout |
L-Carnitine 10mg x 20vialskit price? 20% off with code (paying with crypto) |
20 × 10 mg = 200 mg | $150.00 20% off with code (paying with crypto) $7.50 per vial |
$0.750 | Buy |
Chimera Peptides #19 by metascore |
Metascore 84Finnrick 87%Bought vials 101% of label · 27 testsTitrateLab · Peptide CriticNo report for thisOnline checkout |
L-Carnitine 10ml x 10vials 20% off with code (paying with crypto) |
10 × 10 ml | $89.00 20% off with code (paying with crypto) $8.90 per vial |
– | Buy |
Bio Pepz #98 by metascore · US |
Metascore 76 medium confidenceFinnrick 82%Bought vials 110% of label · 4 testsTitrateLabNo report for thisAccount needed |
L-CARNITINE 10ML | 1 × 10 ml | $35.00 | – | Buy |
Peptides Book #186 by metascore |
Metascore 73 medium confidenceFinnrick 81%Bought vials 92% of label · 3 testsTitrateLabNo public reportsOnline checkout |
L-carnitine 600ml*10vials | 10 × 600 ml | $149.00 $14.90 per vial |
– | Buy |
Peptides Book #186 by metascore |
Metascore 73 medium confidenceFinnrick 81%Bought vials 92% of label · 3 testsTitrateLabNo public reportsOnline checkout |
L-carnitine 1200ml*10vials | 10 × 1200 ml | $201.00 $20.10 per vial |
– | Buy |
Ignite Labs #178 by metascore |
Metascore 73 medium confidenceFinnrick 80%Bought vials 104% of label · 3 testsTitrateLab · PeptideBaseNo public reportsOnline checkout |
Ignite Metabolic Research Blend -Super Shredder | 1 vial, size not stated | $72.99 | – | Buy |
Ignite Labs #178 by metascore |
Metascore 73 medium confidenceFinnrick 80%Bought vials 104% of label · 3 testsTitrateLab · PeptideBaseNo public reportsOnline checkout |
L-Carnitine | 1 × 10 ml | $49.99 | – | Buy |
Modern Aminos Affiliate #125 by metascore · US |
Metascore 75 medium confidenceFinnrick 79%PepIndex 81/100Bought vials 100% of label · 5 testsTitrateLab · PeptideBase · Peptide CriticNo report for thisOnline checkout |
Carnitine / Choline Based Amino Blend $30 off through this site's link (new customers) |
1 vial, size not stated | $49.00 $30 off through this site's link (new customers) |
– | Buy |
Modern Aminos Affiliate #125 by metascore · US |
Metascore 75 medium confidenceFinnrick 79%PepIndex 81/100Bought vials 100% of label · 5 testsTitrateLab · PeptideBase · Peptide CriticNo report for thisOnline checkout |
Carnitine + Arginine Based Amino Blend (20ML) $30 off through this site's link (new customers) |
1 × 20 ml | $44.00 $30 off through this site's link (new customers) |
– | Buy |
Modern Aminos Affiliate #125 by metascore · US |
Metascore 75 medium confidenceFinnrick 79%PepIndex 81/100Bought vials 100% of label · 5 testsTitrateLab · PeptideBase · Peptide CriticNo report for thisOnline checkout |
L-Carnitine (20ML) $30 off through this site's link (new customers) |
1 × 20 ml | $51.00 $30 off through this site's link (new customers) |
– | Buy |
EZ Peptides #12 by metascore |
Metascore 85Finnrick 75%Bought vials 103% of label · 11 testsTitrateLab · PeptideBase · Peptide CriticNo report for thisConfirmed with lab: 21 of 21Account needed |
L-Carnitine 10ml Buy 2, get the 3rd free with code (same item) |
1 × 10 ml | $52.99 Buy 2, get the 3rd free with code (same item) |
– | Buy |
Atomik Labz Affiliate #85 by metascore · US. Florida, 33411 |
Metascore 77Finnrick 69%Bought vials 112% of label · 44 testsTitrateLab · Peptide CriticNo report for thisOnline checkoutCheck vendor |
L-Carnitine 20ml | 1 × 20 ml | $65.00 | – | Buy |
Evolve BioPep #134 by metascore · US |
Metascore 74Finnrick 66%Bought vials 103% of label · 11 testsTitrateLab · Peptide CriticLab report (image)Online checkout |
L-Carnitine 10mL | 1 × 10 ml | $29.99 | – | Buy |
Mai Peptide #35 by metascore · China |
Metascore 82Finnrick 60%Bought vials 101% of label · 107 testsTitrateLabNo report for thisConfirmed with lab: 26 of 26Online checkout |
L-carnitine 10ml*10vials | 10 × 10 ml | $100.00 $10.00 per vial |
– | Buy |
Mixing a 600 mg vial
What each common amount of bacteriostatic water gives you on a U-100 insulin syringe. Pick a vial size above to change it.
| Water | Strength | Per 10 units (0.1 mL) | Per unit |
|---|---|---|---|
| 1 mL | 600 mg/mL | 60,000 mcg | 6,000 mcg |
| 2 mL | 300 mg/mL | 30,000 mcg | 3,000 mcg |
| 3 mL | 200 mg/mL | 20,000 mcg | 2,000 mcg |
| 5 mL | 120 mg/mL | 12,000 mcg | 1,200 mcg |
Published lab results
3 certificates of analysis that vendors publish for L-Carnitine. Numbers are only filled in where the document is readable text; image-only COAs are linked without numbers. A vendor's own COA shows one tested sample, not every batch.
| Vendor | Lab | Date | Label | Measured | Purity | Batch | |
|---|---|---|---|---|---|---|---|
Simple Peptide |
Freedom Diagnostics | 2026-09-03 | – | 429.13 mg | 97.85% | LCARN500-082026-6 (FD #2609010475, client 'Simple Peptide') | View |
Orbitrex Peptides |
Vanguard Laboratory | 2026-07-28 | 5000 mg | – | – | LCARN26B | View (image) |
Evolve BioPep |
Ethos Analytics | 2026-07-15 | – | – | – | ELC-260707-H6 | View (image) |
What the research says
Several meta-analyses of randomized human trials agree that oral L-carnitine produces a small extra weight loss (roughly 1 kg on average), mainly in people with overweight or obesity, with no consistent effect on waist size or body-fat percentage. Trials are heterogeneous and most used oral supplements, not injections.
Key papers ✓ 6✗ 1~ 1
-
The Effect of the L-Carnitine Supplementation on Obesity Indices: An Umbrella Meta-Analysis.Humans16k people8 meta-analyses pooledInterventions of 8 to 30 weeksUmbrella meta-analysis (random-effects)
Umbrella meta-analysis of 8 meta-analyses (16,352 participants): L-carnitine reduced body weight (effect size -1.11), BMI and waist circumference, though heterogeneity was high.
Key resultL-carnitine decreased weight (ES = -1.11; 95% CI -1.90, -0.33, p = 0.005), BMI (ES = -0.33; p = 0.026) and WC (ES = -1.34; p < 0.001)
Study details
- Studied
- Participants in trials of L-carnitine supplementation pooled by eight meta-analyses
- Compared with
- Placebo or control
- Main outcome
- Body weight, BMI and waist circumference
- Sample
- 8 meta-analyses, 16,352 participants
- Authors' conclusion
- L-carnitine supplementation can manage weight, BMI and waist circumference reduction and might help treat obesity.
- Limitations
- High heterogeneity (I2 = 90.6% for weight); concerns L-carnitine alone, one possible ingredient of lipotropic blends.
-
Effects of l-carnitine supplementation on weight loss and body composition: A systematic review and meta-analysis of 37 randomized controlled clinical trials with dose-response analysis.Humans2,292 people37 RCTs pooledSystematic review and meta-analysis of RCTs with dose-response analysis
Meta-analysis of 37 RCTs (2,292 adults): L-carnitine lowered body weight by 1.21 kg and fat mass by 2.08 kg versus control; no significant effect on waist circumference or body-fat percent.
Key resultBody weight WMD -1.21 kg (95% CI -1.73, -0.68; P < 0.001); BMI WMD -0.24 kg/m2 (P = 0.001); fat mass WMD -2.08 kg (P = 0.003); no significant effect on waist circumference or body fat percent
Study details
- Studied
- Participants in 37 randomized controlled trials of l-carnitine supplementation
- Compared with
- Control
- Main outcome
- Body weight, BMI, fat mass, waist circumference, body fat percent
- Sample
- 37 RCTs, 2292 participants
- Authors' conclusion
- L-carnitine provides a modest reducing effect on body weight, BMI and fat mass, especially among adults with overweight/obesity; 2000 mg/day gave the maximum effect on weight.
- Limitations
- Only body weight effect confirmed in high-quality RCTs alone.
-
Beneficial effects of l-carnitine supplementation for weight management in overweight and obese adults: An updated systematic review and dose-response meta-analysis of randomized controlled trials.Humans43 RCTs43 RCTs pooledSystematic review and dose-response meta-analysis of RCTs
Meta-analysis of 43 RCTs: weight fell 1.13 kg and BMI 0.36 kg/m2 versus control, with effects seen only in overweight/obese adults; body-fat percentage and waist circumference did not change significantly.
Key resultWeight WMD -1.129 kg (95% CI -1.590, -0.669); BMI WMD -0.359 kg/m2 (95% CI -0.552, -0.167); fat mass WMD -1.158 kg; no change in body fat percentage or waist circumference
Study details
- Studied
- Participants in 43 randomized controlled trials of l-carnitine supplementation
- Compared with
- Control
- Main outcome
- Weight, BMI, fat mass, body fat percentage, waist circumference
- Authors' conclusion
- L-carnitine might have positive effects on body weight and BMI, especially in overweight and obese subjects; no anthropometric change in hemodialysis patients.
- Limitations
- High heterogeneity for BMI (I2 85.2) and body fat percentage (I2 98.2).
-
The effect of (L-)carnitine on weight loss in adults: a systematic review and meta-analysis of randomized controlled trials.Humans911 people9 RCTs pooledSystematic review and meta-analysis of RCTs (random effects)
Meta-analysis of 9 RCTs (911 adults): carnitine groups lost 1.33 kg more than controls, but the effect shrank the longer supplementation continued.
Key resultWeight MD -1.33 kg (95% CI -2.09 to -0.57); BMI MD -0.47 kg/m2 (95% CI -0.88 to -0.05)
Study details
- Studied
- Adults in nine randomized controlled trials of carnitine
- Compared with
- Control group
- Main outcome
- Weight loss and BMI
- Sample
- 9 RCTs, total n = 911
- Authors' conclusion
- Carnitine resulted in weight loss; the magnitude of weight loss decreased significantly over time of consumption (p = 0.002).
- Limitations
- Only nine trials pooled.
-
The Effects of L-Carnitine Supplementation on Weight Loss, Glycemic Control, and Cardiovascular Risk Factors in Patients With Type 2 Diabetes: A Systematic Review and Dose-response Meta-Analysis of Randomized Controlled Trials.Humans2,041 people21 RCTs pooledSystematic review and dose-response meta-analysis of RCTs (GRADE rated)
Meta-analysis of 21 RCTs in 2,041 people with type 2 diabetes: small reductions in BMI, HbA1c, LDL cholesterol and fasting glucose; authors urge caution because of very high heterogeneity.
Key resultPer 1 g/d: BMI MD -0.37 kg/m2 (95% CI -0.59, -0.15); HbA1c MD -0.16% (95% CI -0.32, -0.01); LDL-C MD -0.11 mmol/L (95% CI -0.16, -0.05)
Study details
- Studied
- Adults with type 2 diabetes in 21 randomized trials
- Compared with
- Control
- Main outcome
- BMI, HbA1c, LDL cholesterol and other cardiometabolic markers
- Sample
- 21 RCTs, 2041 patients with type 2 diabetes
- Authors' conclusion
- L-carnitine produced a small reduction in serum lipids and plasma glucose in type 2 diabetes, but given high heterogeneity the results should be interpreted very cautiously.
- Limitations
- High statistical heterogeneity (I2 91 to 94%).
-
Effects of L-Carnitine Supplementation on the Rate of Weight Gain and Biomarkers of Environmental Enteric Dysfunction in Children with Severe Acute Malnutrition: A Double-Blind Randomized Controlled Clinical Trial.Humans98 peopleRandomizedPlacebo-controlledDouble-blind15 daysDouble-blind placebo-controlled randomized clinical trial
Double-blind RCT in 98 children with severe acute malnutrition: L-carnitine syrup did not change rate of weight gain or gut-dysfunction biomarkers versus placebo.
Key resultRate of weight gain 2.09 ± 2.23 vs 2.07 ± 2.70 (P = 0.973) for L-carnitine vs placebo
Study details
- Studied
- Children aged 9-24 months with severe acute malnutrition, Dhaka, Bangladesh
- Compared with
- Placebo
- Main outcome
- Rate of weight gain; enteric dysfunction biomarkers
- Sample
- 98 children with severe acute malnutrition
- Authors' conclusion
- L-carnitine (100 mg/kg/d) had no additional effect on severe acute malnutrition; longer trials, possibly with other combinations, are recommended.
- Limitations
- Short supplementation (15 days).
-
The bright and the dark sides of L-carnitine supplementation: a systematic review.Humans11 studies in healthy humans11 studies pooled12 or 24 weeksSystematic review
Review of 11 studies of 12-24 weeks of oral L-carnitine in healthy people: some gains in muscle carnitine and function in specific groups, but supplementation raised fasting plasma TMAO, a compound suspected to be pro-atherogenic.
Study details
- Studied
- Healthy humans supplemented orally with L-carnitine for at least 12 weeks (1 to 4 g/day)
- Main outcome
- Metabolism and metabolic modifications
- Authors' conclusion
- Prolonged LC supplementation may affect physical performance in specific conditions, but raises fasting plasma TMAO, a supposedly pro-atherogenic compound; long-term cardiovascular studies are needed.
- Limitations
- Small set of studies; long-term cardiovascular effects unstudied.
-
Risk assessment for carnitine.No new dataRisk assessment review
Safety risk assessment of supplementation trials: found strong evidence of safety for chronic intake at commonly studied levels, with insufficient data to judge long-term safety at higher intakes.
Study details
- Main outcome
- Safety of carnitine supplementation
- Authors' conclusion
- Using the observed safe level method, evidence of safety is strong up to 2000 mg/day l-carnitine for chronic supplementation; data above that are insufficient for a confident conclusion of long-term safety.
Reported side effects
- reportedRaised fasting plasma TMAO (a possible cardiovascular risk marker) [ref]
Abstracts describe oral L-carnitine as generally well tolerated; long-term cardiovascular relevance of the TMAO rise is unknown, and injectable L-carnitine for weight loss was not studied in these papers.
202 registered human trials (24 active)
✓ positive · ✗ negative · ~ mixed · ? inconclusive, judged on each paper's own main outcome. Grades: A strong human evidence → D little or none. Papers and verdicts are drawn from PubMed, Europe PMC and Russian journals (CyberLeninka); not medical advice.
Registered clinical trials 202 on ClinicalTrials.gov · 24 active · 113 completed · 20 with posted results
All 202 L-Carnitine trials, with countries and summaries · Search ClinicalTrials.gov · Recruiting trials for every peptide
Discussions elsewhere
Experiences and questions about L-Carnitine on other sites. Treat anecdotes with care.
Also sold in blends with L-Carnitine
L-Carnitine + Vitamin B12 (1). The order planner uses these automatically when a blend is cheaper than separate vials.
L-Carnitine: questions people ask
What is L-Carnitine?
Amino-acid derivative (not a peptide). Carries fatty acids into mitochondria so they can be burned for energy. Injectable carnitine treats carnitine deficiency; weight-loss benefits are not well established.
How much does L-Carnitine cost?
The cheapest L-Carnitine from an independently tested vendor is $0.003 per mg (Shanghai Wibson Biotechnology WBS, L-carnitine 5000mg/10ml*10vials (China warehouse) [jinjier], $150.00). Across 38 listings from 22 vendors the median is $0.009 per mg.
Where can I buy L-Carnitine?
22 vendors tested by Finnrick sell L-Carnitine. The cheapest per mg right now: Shanghai Wibson Biotechnology WBS ($0.003), Amino Usa ($0.005), Andy Peps Studio ($0.005). 1 of them publish a lab report (COA) for L-Carnitine; compare lab scores and reports in the table above before buying.
How much bacteriostatic water for 600 mg of L-Carnitine?
Adding 2 mL of bacteriostatic water to a 600 mg vial of L-Carnitine gives 300 mg/mL: each 10 units on a U-100 insulin syringe holds 30,000 mcg. With 1 mL it's 600 mg/mL (60,000 mcg per 10 units); with 3 mL, 200 mg/mL (20,000 mcg per 10 units). More water makes small amounts easier to measure. Mixing charts: 500 mg, 600 mg, 1,200 mg, 5,000 mg.
Is L-Carnitine FDA approved?
Prescription injectable in the US (Carnitor) for carnitine deficiency; also a supplement.
Can L-Carnitine be compounded in the US?
FDA-approved as levocarnitine (Carnitor). Compounding status for every peptide.
Does L-Carnitine work? What does the research say?
Evidence grade A (strong human evidence), from 8 papers: Several meta-analyses of RCTs (37-43 trials, over 2,000 people) agree on a small extra weight loss of about 1 kg, mainly in overweight adults. Several meta-analyses of randomized human trials agree that oral L-carnitine produces a small extra weight loss (roughly 1 kg on average), mainly in people with overweight or obesity, with no consistent effect on waist size or body-fat percentage. Trials are heterogeneous and most used oral supplements, not injections. See the papers.
Are there clinical trials of L-Carnitine?
ClinicalTrials.gov lists 202 registered trials of L-Carnitine: 24 active, 113 completed, 43 in phase 3, 20 with posted results. Examples: Studying the Effect of Levocarnitine in Protecting the Liver From Chemotherapy for Leukemia or Lymphoma (Active, not recruiting, Phase 3, 440 people); Trial on the Biological and Clinical Effects of Acetyl-L-carnitine in ALS (Recruiting, Phase 2, Phase 3, 246 people); Using Gut Microbial Gbu Gene Testing to Estimate Host TMAO Production Capacity (Active, not recruiting, 230 people).
What are the side effects of L-Carnitine?
Reported in the research: Raised fasting plasma TMAO (a possible cardiovascular risk marker). Abstracts describe oral L-carnitine as generally well tolerated; long-term cardiovascular relevance of the TMAO rise is unknown, and injectable L-carnitine for weight loss was not studied in these papers.