Treatment of Schizophrenia with Quetiapine and Zotepine

Mechanism of Action

The American Academy of Child and Adolescent Psychiatry notes that both quetiapine and zotepine are atypical antipsychotics that act as antagonists of dopaminergic and serotonergic receptors, differing from traditional typical antipsychotics which are predominantly dopaminergic antagonists (specifically D2) 1, 2
Atypical antipsychotics affect multiple neurotransmitter systems, contributing to their differentiated profile of efficacy and side effects 2, 3

The American Academy of Child and Adolescent Psychiatry recommends quetiapine as a safe and effective treatment in an open study with 10 young patients with schizoaffective disorder or bipolar disorder 1, 2
There are case reports describing the efficacy of quetiapine in a 14-year-old boy with schizophrenia and a 15-year-old girl with acute psychotic episode 1, 4

Quetiapine is associated with significant weight gain, being the most common problem associated with its use 5
Quetiapine has a lower risk of extrapyramidal symptoms compared to typical antipsychotics 1, 2
Quetiapine may produce changes in the electrocardiogram, specifically prolongation of the QT interval 6
Quetiapine is associated with rare cases of leucopenia and significant decrease in absolute neutrophil and platelet count 6, 5
Quetiapine may cause elevations in liver transaminases 6
Quetiapine is associated with the development of cataracts in dog studies, although this effect has not been reported in humans 6

The choice between antipsychotics should be based on the relative potency of the agent, potential side effects, and the patient's history of response to medication 7, 4
Atypical antipsychotics are generally preferred over traditional neuroléptics due to the lower risk of extrapyramidal symptoms 1, 2
Individual responses to different antipsychotics are variable, and if insufficient effects are evident after a 6-week trial using adequate doses, a different antipsychotic agent should be tried 7, 4

There are more studies available on quetiapine than on zotepine, especially in young populations 1, 2, 4
More studies are needed to establish the efficacy and safety of both medications in young patients 1, 2