Threonine is used to treat various nervous system disorders including spinal spasticity, multiple sclerosis, familial spastic paraparesis, and amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease). Useful with intestinal disorders and indigestion, threonine has also been used to alleviate anxiety and mild depression. . L-threonine has been used clinically with the aim of increasing glycine concentrations in the cerebral spinal fluid of patients with spasticity.