) dose not cause depression
and is in fact sometime used to boost antidepressant effect of other antidepressant because it enhance dopamine and norepinephrine
which can improve depression, fatigue and sleepiness.
It has a known side effect of causing lack of appetite
) and if you are noticing the same this could be the reason behind your current symptoms.
A good strategy to deal with side effect is to reduce the dose and see if it helps. Your doctor has already reduce the dose and you are noticing improvement which is a good sign.
I hope this helps, please feel free to discuss further if you have any other query.