A 35-year-old woman with a known history of bipolar I disorder, currently on lithium, presents to her psychiatrist reporting increased energy, decreased need for sleep, rapid speech, and grandiose thoughts for the past week. Her lithium level is therapeutic. What is the most appropriate initial adjustment to her treatment regimen?
✓ Correct Answer: Option C
The patient is experiencing an acute manic episode despite a therapeutic lithium level. The most appropriate initial step is to add an antipsychotic (e.g., olanzapine, risperidone) to rapidly control the manic symptoms, as adding an antidepressant can worsen mania.