is l-carnitine hard on the kidneys History of L-carnitine: Implications for renal disease NuEthix Formulations Lipsomal L-Carnitine Supplement

The endogenous biosynthesis which mainly takes place in the liver, kidney, and to some extent in the brain, meets only 25% of the carnitine required by the human body, while the remaining 75% is obtained from the diet under regular diet regimen, i.e., consuming either meat, fish, dairy product, and vegetables (Pochini et al., 2013

Jacoba JKGC, Abarquez RF, Topacio GO, et al

However, an earlier review reported no improvement in reaction time, immediate memory or delayed recall in young adults with cognitive impairment

Acetyl L-Carnitine 750, also called ALCAR, may be the most effective form of the amino acid carnitine