Ditto Josefa 100%. Some doctors are starting to question the whole serotonin-deficit hypothesis anyway, it may turn out to be one more example of following shaky science toward its lucrative ends for Big Pharma.
Start with nutrition (especially good sources of magnesium, zinc, and B vitamins, and cut out seed oils and excess sweets), daily exercise -- even just a quick walk -- out in the fresh air and sunshine for Vitamin D, and better sleep: try to go to bed earlier and wake up earlier too. Sometimes that will be enough to begin to improve a person's ability to deal with everyday difficulties. It won't automatically make troubles go away, but it does help a person to perceive life more clearly.
And don't forget prayer! Our Mother of Perpetual Help, and Mary, Undoer of Knots are recommended, and the Psalms too.
Indeed! Eggs, bad. Sun, bad. Fat, bad. Sugar, bad. Fruit, bad. Fiber bad. Chemo, good. Radiation, good. Vaccines, good. Pharmaceuticals, good.
I heard just the other day that they now think a torn ACL heals itself over time. I tore mine and was pressured to have it surgically repaired, as in "it will never heel and you'll need knee replacement ultimately."
As I don't want human jerky in my body, I told them to get lost.
Gee, almost fifteen years later, still walking.