Just a quick experience report. I’ve been on low doses of tricyclic antidepressants for 3 weeks now for chronic pain (from elbow tendinitis). They are working great! Within a few days of starting I was in a lot less pain (note: antidepressant effects take 3-4 weeks to set in, so this is definitely not a change in depression-caused pain). I still get overuse pain and you’ve-been sitting in an unergonomic chair. Too-long pain and random I feel like-tormenting you just because pain but the background level of constant pain is reduced. Also before the new medication I was very sensitive to changes in weather, but we just had a large temperature drop and I still feel just as good. So I’d say if you’re interested (and/or desperate as I was!) they are worth a try.
Comment: The Oxford Pain Internet Site (http://www.medicine.ox.ac.uk/bandolier/) has got some information about the effectiveness of different kinds of pain relief, including the use of antidepressants for chronic pain. Lots of useful stuff on this site.