Olanzapine misuse is a serious public health problem, among opiate-dependent patients in methadone program as it puts the patients at risk of life-threatening drug overdoses. However there is no study to assess how serious the problem is and what factors associated with Olanzapine abuse.

This study estimates the prevalence of olanzapine misuse in methadone program, and provides information on characteristics of olanzapine users.

A pilot study done in Drug Treatment Centre in Dublin and a survey was carried out at the methadone program. The patients were invited to participate in the survey on voluntary basis. Of the 25 patients invited to partcipate in the survey, 22 patients completed the survey.

13 out of 22 respondents had a history of olanzapine use, and out of 13 user only 5 had been prescribed Olanzapine for Co-morbid psychiatric conditions and the remaining 8 respondents used olanzapine without prescription. Out of the 8 users, 5 of them is regularly using 30–40 mg per day of olanzapine and had used 30/30 days in the last month. The remaing 3 users is intermittently using olanzapine. The current users reported more mental health problems like Anxiety, sleep disorder, and stress in the past 6 months.

The information on epidemiology of Olanzapine misuse suggest that most methadone programs do not address co-existing anxiety, sleep disorders and psycho-social stress. Based on the pilot study, a further study is currently undergoing which includes 200 opiate dependent patients on methadone program in Drug Treatment centre in Dublin.