Clozapine is an effective medication in the treatment of schizophrenia, especially when a person has not responded to trials of other antipsychotic medications. However, it is associated with high rates of metabolic syndrome (i.e., high blood pressure, high blood sugar, high cholesterol, increased body fat) which raises a person’s risk of heart disease and other health problems, such as diabetes.
Among users of all antipsychotic medications there is increasing evidence that metformin, a biguanide antihyperglycaemic drug commonly used in the management Type 2 Diabetes, assists in management of weight gain. A recent meta-analysis showed that metformin can lead to a greater than 3 kilogram weight loss amongst individuals who experienced obesity whilst taking clozapine. We want to further investigate if giving metformin to people newly commenced on clozapine results in less weight gain compared to people who are just being treatment with clozapine alone.