Background: Antipsychotic medications are the mainstay of treatment for schizophrenia. Medication non-adherence can lead to relapse and functional decline. Nevertheless, antipsychotic non-adherence rates remain significant. Long-acting injectable antipsychotics (LAIs) offer several advantages over oral antipsychotics, including improved adherence, reduced hospitalisation rates and reduced mortality. Objectives: To investigate the proportion of people with psychosis who are on LAIs; the difference in the demographic, clinical, substance use and adverse drug reaction profiles of people taking LAIs compared to oral antipsychotics; and the differences in the same profiles of those on first-generation antipsychotic vs second-generation antipsychotic LAIs. Methods: Data were collected as part of the Survey of High Impact Psychosis. Findings: Nearly one-third (31.5%) of people with psychosis were on LAIs, of whom 49.7% were on first-generation LAIs and 47.9% were on second-generation LAIs. Compared to those on the oral formulation, people on LAIs were almost four times more likely to be under a community treatment order. Furthermore, people on LAIs were more likely to have a longer duration of illness, reduced degree of insight, increased cognitive impairment as well as poor personal and social functioning. They also reported more adverse drug reactions. Conclusion: LAIs use in Australia is associated with higher rates of community treatment order use, as well as poorer insight, personal and social performance, and greater cognitive impairment. While LAIs may have the potential to improve the prognosis of people with psychosis, a better understanding of the choices behind the utilisation of LAI treatment in Australia is urgently needed.