I had been in an awful depression about 2 years ago and nothing was working. I asked my pdoc for ECT and she said we could look into it, but she wanted to try one more medication. It was Pristiq. It has been a miracle for me.
The only side effect I have from it is heat intolerance and hot flashes. I had those at the higher dose. Not great saide effects, but much, much better than depression.
I encourage you to try Pristiq. btw, 25mg is extremely low.