Objective: To improve poor medication adherence in schizophrenic patients, long-acting injectable (LAI) antipsychotics are used. However, it has not yet become common in Japan. Recently, aripiprazole LAI was approved for alternative injection into the deltoid muscle in addition to the gluteal muscle. The acceptance for the proposal to switch from gluteal to deltoid injections of aripiprazole LAI was investigated. Methods: The subjects were 32 outpatients with schizophrenia who had continuously received aripiprazole LAI administration into the gluteal muscle for ≥ 6 months. In the patients who had continued deltoid injection for 3 months after switching, the changes in the pain and shame in comparison with gluteal injections were evaluated. Results: Switching to the deltoid injection was chosen by 17 out of 32 patients. Three months later, 9 patients were still receiving deltoid injections with highly rated satisfaction. The main reasons for switching to deltoid injections included the pain and shame associated with gluteal injections. The main reason for returning to the gluteal injection was the pain experienced from the injection in the deltoid. Conclusion The option to select the injected area was based on the amount of pain in the deltoid and gluteal sites, leading to the widespread use of aripiprazole LAI.