People respond to different medicines in different ways, and what may be very effective for one person may simply "poop out" or not work at all in another person. The various antidepressants affect different parts of the brain which could be causing your depression. The drugs you have tried so far may be having little effect on the brain area related to YOUR depression. Since you have not responded to tricyclics well in the past, I suspect Pamelor, another tricyclic, will not have much effect. At this point, I would be considering an antidepressant in another class altogether. There are several different classes of these drugs you haven't used yet. Unfortunately, sometimes finding the right antidepressant takes a lot of trial and error. There are some blood tests now that can help your doctor choose one that might be more effective for you. Talk to your doctor about these possibilities. Hope this helps.