Frontiers Age and APOE affect L carnitine system metabolites in the brain in the APOE TR model Frontiers Association between fatigue, peripheral serotonin, and L carnitine in hypothyroidism and in chronic fatigue syndrome LCarnitine Research & Benefits Studies & Scientific Use Carnitine can be a game changer for those with NF. It helps build muscle, improves learning problems, and reduces nerve pain. Who takes it? LeanShots Liquid L Carnitine Shot (3000mg) NutraBio Brands