Background: L-carnitine is a quaternary ammonium compound. It and its two derivatives,(acetyl-L-carnitine and propionyl-L-carnitine), are considered essential amino acids. L-carnitine has been shown to improve physical performance in patients with certain diseases, including advanced cancer, fatigue, metabolic syndrome, and cardiovascular disease. L-carnitine is an important factor in the metabolism of long-chain fatty acids to produce energy. It exhibits a wide range of biological activities including anti-inflammatory, antiapoptotic, neuroprotective, and gastroprotective properties. L-carnitine prevents oxidative stress and regulates nitric oxide, cellular respiration, and the activity of enzymes included in defense against oxidative damage. Furthermore, these effects are attributed to its antioxidative and free radical scavenging activity. It also acts on cellular DNA and membranes, protecting them against destruction induced by free oxygen radicals.

Aim: The current review provides the evaluation of l-carnitine, outlining its clinical applications as well as its mechanism of action.

Conclusion: In summary, researchers have frequently emphasized the significance of l-carnitine administration as the cornerstone for protection against various diseases.