Deplin can be used in people who suffer from depression and are taking antidepressants that don't seem to be working too well. Some reasons for antidepressants not working so well is that some people with depression suffer from a form of folic acid deficiency where their body does not metabolize enough folic acid into Deplin, or L-Methylfolate. L-Methylfolate is the only form of folic acid that breaks the blood-brain barrier. What it does is it creates more neurotransmitters that lead to the serotonin, norepinephrine, and dopamine receptors. Since most antidepressants effect serotonin and/or norepinephrine and sometimes the dopamine receptors, Deplin creates more neurotransmitters so your receptors can take in more of the antidepressant(s) you are on. Hope this helps! Sorry if not, it's my first post!