[Psychopharmaceuticals in chronic pain]. 
Since the introduction of psychotropic drugs, especially carbamazepine (Tegretol), antidepressants and neuroleptics, the treatment of all chronic and severe pain has been decisively improved.  Psychotropic drugs have an analgesic effect, and potentiate and economize analgesics.  The essential advantage is the absence of dependence during long term treatment.  The alleviation of pain is caused by "depersonalization of the pain" or by a "pain removing effect" through a favourable influence on central pain perception and sensation.  They prevent the sometimes fatal vicious circles: pain leads to anxiety leads to depression leads to pain etc.  or: pain leads to increased central nervous excitability leads to psychic reaction leads to pain etc.  The antidepressants induce a change in the central metabolism of serotonin and noradrenaline.  Serotoninergic and noradrenergic (pain)-inhibitory neurons are involved in the analgesic effect of exogenous and endogenous opiates.  Some neuroleptics (e.g. haloperidol) have a stereospecific binding capacity to opiate receptors and have an opiate-agonistic effect.