Psychosis in childhood and adolescence could be defined as having hallucinations, with the hallucinations occurring in the absence of insight. A broader definition includes symptoms such as delirious thoughts, disorganized speech, disorganized behavior, cognitive and mood symptoms and what is called negative symptoms. Several researches have been done focused in the treatment of first episode of psychosis showing clozapine as a keystone in the treatment of psychosis, especially in refractory first episodes.

Clozapine has unique efficacy in improving treatment-resistant patients with chronic schizophrenia but the moment of instauration remains unclear. There have always been doubts about the right moment to start clozapine, after two or more previous anti-psychotics or as first option.

We report a 18-year- old woman with family history of severe psychosis. Her mum reasserted patient's symptoms contributing to a longer period of non-treating psychosis (about 10 months). Auditory hallucinations, incongruent mood and incoherent language appeared for the first time at the age of 17. High doses of two consecutive anti-psychotics were tried without remission and finally clozapine was initiated with clinical improvement.

In clinical practice, a subgroup of psychotic patients experience, significant ongoing positive symptoms despite of using first line anti-psychotic medication.

Most recent research; suggest that clozapine may have an important role in the early treatment of first-episode patients, even becoming a first line option to consider.

The authors have not supplied their declaration of competing interest.