An Adverse drug reaction cannot be avoided especially with drugs like antipsychotics which are the mainstay for the treatment of schizophrenia, a chronic disease, as well for the treatment of psychosis. Hence monitoring of adverse drug reactions is the key factor in ensuring patient compliance and safety. This study was a prospective, descriptive, follow up study. The reported ADRs were assessed for causality using both WHO causality assessment scale and Naranjo’s algorithm. The severity of the reported reactions was assessed using Modified Hartwig and Siegel scale. The predictability and preventability of the reported ADRs was assessed using developed criteria for determining predictability of an ADR and Modified Schumock and Thornton scale respectively. A total of one hundred and forty three adverse drug reactions were observed from One hundred and two patients that were recruited. ADR’s were noted and the majority of these adverse reactions was seen with Olanzapine and Risperidone. These include weight gain, sedation, tremors, drug induced parkinsonism and disturbances in menstrual cycle. Mild ADR’s using Hartwig scale were fatigue, dry mouth, insomnia, weight gain and GI disturbances. Moderate ADR’s were tardive dyskinesia, pill rolling movements, drug induced parkinsonism and hyper salivation. Severe reactions included disturbances in lipid profile, delirium, menstrual disturbances and hypertension Of the ADR’s, 92% were predictable and 7.4% unpredictable. 67.8% ADR’s were not preventable, 29.6% ADR’s were definitely preventable and 3.70% probably preventable. WHO causality assessment revealed 55.5% ADR’s to be certain, 29.6% to be probable and 14.8% to be possible. Need of the hour is active surveillance of adverse drug reaction with an efficient pharmacovigilance centre in every established hospital.
Key words: Adverse drug reaction, World Health Organization, Pharmacovigillance, Atypical antipsychotics, Schizophrenia.