Acetyl l carnitine deficiency in patients with major depressive disorder PNAS Dr Acetyl l carnitine has been compared to placebo treatments. It's also been compared to standard antidepressants. Most of those studies lead to the conclusion that acetyl l carnitine works like ProCaps Laboratories Acetyl L Carnitine 400 Chronic acetyl L carnitine treatment alleviates behavioral deficits and neuroinflammation through enhancing microbiota derived SCFA in valproate model of autism ScienceDirect