The purpose of this registry is to explore adherence to treatment, the occurrence of adverse drug reactions and the clinical outcomes in a sample of patients under treatment with atypical antipsychotics in several Central American countries. For this study, clinical data will be extracted from the medical records of 1000 patients with schizophrenia, depressive disorders or Parkinson's Disease with hallucinations. Occurrence of adverse drug reactions, namely weight gain, somnolence, extrapyramidal reactions and symptoms of orthostatic hypotension; adherence to treatment; and changes in quality of life and clinical status will be assessed during the first 8 weeks of treatment.