What is the best maintenance dose of neuroleptics in schizophrenia?

Short-term use of neuroleptics as well established for many psychotic disorders; details about long-term use remain less clear. Most long-term studies involved patients diagnosed as chronic schizophrenics and used phenothiazines; responses, dose requirements, and probably diagnosis were highly heterogeneous. Data from controlled studies permitting estimates of the equivalent dose of chlorpromazine to be plotted vs. reduction of relapse rates revealed no significant dose effect between 100 and over 2,000 (median = 310) mg/kg day, no mean difference in outcome at doses above vs. below 310 mg, and a mean relapse of placebo of only 54%. Since maintenance requirements for some patients may be low, the use of minimum effective doses is encouraged and may limit risks of late toxicity, as further long-term studies of the effect of dose are undertaken.