acetyl-l-carnitine anxiety reddit L-carnitine and Acetyl-L Carnitine: A Possibility for Treating Alterations Induced by Obesity in the Central Nervous System | Neurochemical Research Ketogenic Diets for Body Weight
Description
doi: 10.1016/j.bjps.2006.04.017

ALC has contributed to enhanced learning capacity and cognitive function in rats by providing acetyl groups for acetylcholine synthesis, thereby exerting an effect in cholinergic neurotransmission ( 4.1 Limitations Small animal models provide advantages in the study of TBI in the ability to screen for pathology that is otherwise hard to determine

So, there's no official daily requirement or recommended intake to follow
Minocycline supplementation for treatment of negative symptoms in early-phase schizophrenia: A double blind, randomized, controlled trial
