Hello. So Bipolar disorder is a chronic illness which is managed in 2 stages firstly the acute phase and secondly the maintenance phase. Lithium is one of the first line agents used for BPAD in both phases. It even has a neuroprotective role. If a patient is not responding to Lithium other agents such as Valproate or antipsychotics can be considered. But that decision depends on patients overall profile, h/o substance use and any medical comorbidity if present. Hence it varies from patient to patient.