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)