Safety Profile
Overall safety rating: Generally Safe
L-Carnitine Side Effects & Safety
This content is for informational purposes only and does not constitute medical advice. Consult your healthcare provider before starting any supplement. Full disclaimer
Potential Side Effects
- Fishy body odor at higher doses due to trimethylamine production
- Nausea, diarrhea, and abdominal cramps possible
- High chronic doses may increase TMAO levels (potential cardiovascular concern)
Drug & Supplement Interactions
- Anticoagulants (warfarin) — L-carnitine may enhance anticoagulant effects
- Thyroid hormones — L-carnitine may inhibit thyroid hormone action peripherally
- AZT and other nucleoside analogues — carnitine may help mitigate mitochondrial toxicity
Maximum Dose
Do not exceed: 3-6 g/day used safely; doses above 3 g may increase TMAO production (a cardiovascular risk marker)
References
- DiNicolantonio JJ, Lavie CJ, Fares H, et al. (2013). L-Carnitine in the secondary prevention of cardiovascular disease: systematic review and meta-analysis. Mayo Clinic Proceedings. DOI PubMed
- Koeth RA, Wang Z, Levison BS, et al. (2013). Intestinal microbiota metabolism of L-carnitine, a nutrient in red meat, promotes atherosclerosis. Nature Medicine. DOI PubMed
- Spiering BA, Kraemer WJ, Vingren JL, et al. (2007). Responses of criterion variables to different supplemental doses of L-carnitine L-tartrate. Journal of Strength and Conditioning Research. DOI PubMed