Since the beginning of the neuroleptics in 1952, French psychiatrists have proposed a classification of neuroleptics, taking into account the pharmacological and therapeutic differences between these drugs. They distinguished 3 different clinical effects of neuroleptics: sedative effects, effects on the positive symptoms of schizophrenia and effects on the negative symptoms. The effect of some neuroleptics on negative symptoms is recognized by the international community, which considers clozapine to be effective. In France, in most cases, the indication of clozapine is still refractory paranoid schizophrenia. The effect of this atypical neuroleptic on other types of schizophrenic patient is not well known. Remoxipride appears to be as effective in treating psychotic symptoms and to have fewer side effects than haloperidol. Remoxipride is effective for both positive and negative symptoms. Loxapine has been prescribed in France since 1980. Its pharmacological profile is close to that of clozapine: it has dopamine (D2), histamine (H1), serotonin (5-HT2) and adrenergic (alpha 1)-blocking activities. Its best indication seems to be paranoid schizophrenia, although some data suggest bipolar action. The bipolar action of some new neuroleptics is illustrated by amisulpride, a substitute benzamide derivative. The originality of this molecule lies in its two opposite actions at two distinct doses. Doses of 600-1200 mg/day are effective against positive symptoms; 50-150 mg/day improves negative symptoms. This latter effect could be mediated by activation of the dopamine system.(ABSTRACT TRUNCATED AT 250 WORDS)