Welcome to NeuroTalk.

There is a very small subset of depression patients who respond to opiates. This is because the mu receptor can also be involved with the serotonin system.

We have a thread on the bipolar forum about buprenorphine:

http://neurotalk.psychcentral.com/sh...=buprenorphine

Ultram is a weak serotonin acting drug, and has some contraindications about using with SSRI drugs because of that.
This listed interaction describes it:
http://www.drugs.com/drug-interactio...2057-1348.html

This is the full list at drugs.com :
http://www.drugs.com/drug-interactions/tramadol.html

I personally have not seen any of our PN posters here describe antidepressant results with tramadol. I use it myself, but not every day and I don't see that effect either. But the literature describes it as a potential, and it is used often for the pain issues in patients with fibromyalgia which is a central pain condition responding to serotonin.