Recently (Trust medical science at your peril (2): What is the evidence, especially in psychiatry? ) I recommended the newsletter of Mad in America for disseminating reliable information about psychiatric matters. A recent issue of the Newsletter has links to a very thorough examination of the evidence that anti-psychotic drugs make things worse if used long-term: “The case against antipsychotics — A review of their long-term effects”, by Robert Whitaker (July 2016).
There is considerable support for the hypothesis that psychotic episodes are associated with heightened sensitivity to dopamine. Anti-psychotics ameliorate such episodes by blocking dopamine receptors. These drugs appear to be beneficial immediately, and for perhaps as long as a couple of years. However, once exposed to the drugs, withdrawal almost always has severe bad effects.
It appears that the brain tries to overcome the blocking of the dopamine receptors by increasing the number of these receptors. That takes appreciably long time, apparently many months if not years, so the consequences become significantly important only eventually. That explains why withdrawal brings even worse symptoms than the original ones were, and why long-term treatment is more harmful than beneficial. The drugs must be used forever, and their cumulating “side” effects are very debilitating.
Non-drug treatment of schizophrenia and other psychoses, sometimes teamed with short-term drug use, has much better long-term outcomes than does continual medication; better outcomes in terms of better all-around functioning and fewer relapses.