70% of depressed folks are missing stomach enzymes that metabolize vitamin B9 (folic acid)
into folate which can cross the blood-brain barrier to help create more serotonin and
increase serotonin neurotransmitters--they are the "feel good" neurotransmitters.

A relatively new food med called Deplin provides a form of folate that can cross the
blood-brain barrier and is very helpful in alleviating depression. I take it (15 mg. once daily) and wouldn't be without it. It has been the "miracle" drug for me to help in
removing depressive states.

Please ask your psychiatrist about it; it may be that it could be helpful for you. I know
of a couple of people who were medication resistant who have been able to stabilize on
Deplin.

(It's discussed online, too.)

Take care of yourself.