A 28-year-old woman with a past medical history of an unspecified eating disorder comes in for a follow-up of depression. The patient was started on sertraline several months ago but complained of continued depressive symptoms. On the last visit 8 weeks ago, the patient's dose of sertraline was increased. However, she continues to have a depressed mood. Which of the following is the next best step in the treatment of this patient?
1) Admit to the inpatient unit
2) Continue the current dose of sertraline
3) Discontinue sertraline and begin duloxetine
4) Discontinue sertraline and begin buproprion