Review Question - QID 109658

A 51-year-old male presents to his primary care provider for a normal check-up. He reports that he “hasn’t felt like himself” recently. He describes feeling down for the past 8 months since his mother passed away. He has had trouble sleeping and has unintentionally lost 15 pounds. He feels guilty about his mother’s death but cannot articulate why. His performance at work has declined and he has stopped running, an activity he used to enjoy. He has not thought about hurting himself or others. Of note, he also complains of numbness in his feet and fingers and inability to maintain an erection. His past medical history is notable for diabetes. He is on metformin. His temperature is 98.6°F (37°C), blood pressure is 125/65 mmHg, pulse is 90/min, and respirations are 16/min. On exam, he is alert and oriented with intact memory and normal speech. He appears tired with a somewhat flattened affect. The best medication for this patient inhibits which of the following processes?