Can Lcarnitine be used as a treatment for a child with autism spectrum disorder (especially if a metabolic or mitochondrial abnormality is suspected), and what dosing and safety monitoring are recommended? Amazon.com: Nutrex Research L Carnitine 3000 Clinically Dosed L Carnitine Liquid for Energy, Metabolism & Muscle Recovery Delicious Passionfruit Guava No Sugar, No Carbs, No Stimulants 31 Servings : Health & Household CARNITINE (L CARNITINE, ACETYLCARNITINE) Neuroneeds L Carnitine Shows Promise as Supportive Therapy for Autism A clinical trial published in the journal Research in Autism Spectrum Disorders found that l carnitine supplementation may help reduce autism symptoms in children. The Potential Role of L Carnitine in Autism Spectrum Disorder