A 72-year-old man comes to the office for follow-up. Six weeks ago, he was evaluated for symptoms of depressed mood, loss of interest in activities, weight loss, poor concentration, and wishing he were dead. Physical examination and laboratory tests were unremarkable. He was diagnosed with major depressive disorder and started on fluoxetine. At today's visit, he reports feeling 80% better since starting the medication but is having intolerable side effects, including difficulty falling asleep and feeling jittery. On mental status examination, the patient is alert, cooperative, and mildly restless. His mood is minimally depressed and his affect is full. He has no suicidal ideation. He asks if he can try a different antidepressant. Which of the following medications would be most appropriate for this patient?

Question

A 72-year-old man comes to the office for follow-up.  Six weeks ago, he was evaluated for symptoms of depressed mood, loss of interest in activities, weight loss, poor concentration, and wishing he were dead.  Physical examination and laboratory tests were unremarkable.  He was diagnosed with major depressive disorder and started on fluoxetine.  At today's visit, he reports feeling 80% better since starting the medication but is having intolerable side effects, including difficulty falling asleep and feeling jittery.  On mental status examination, the patient is alert, cooperative, and mildly restless.  His mood is minimally depressed and his affect is full.  He has no suicidal ideation.  He asks if he can try a different antidepressant.  Which of the following medications would be most appropriate for this patient?

Quizplus · Accepted Answer

Explanation: This patient has had a positive response to an adequate trial (6 weeks) of the selective serotonin reuptake inhibitor (SSRI) fluoxetine but is experiencing intolerable side effects of insomnia and jitteriness. Although all antidepressants in the SSRI class share the property of blocking the serotonin reuptake pump, they vary considerably in their chemical structure and their likelihood of causing specific side effects. Therefore, some patients who cannot tolerate one SSRI may do well on another. Fluoxetine tends to be activating and is more prone to cause insomnia and jitteriness, as in this patient. This patient is an SSRI responder and will probably benefit from another SSRI that is less likely to cause insomnia and jitteriness, such as escitalopram. In patients who are nonresponders to SSRIs, it would be reasonable to try an antidepressant from a different class. (Choice A) Tricyclic antidepressants have similar efficacy to other classes of antidepressants; however, they are generally used as a second-line treatment due to their unfavorable side effect profile (anticholinergic effects, orthostasis, cardiotoxicity in overdose). They would not be the next step in this patient, who has shown a positive response to an SSRI. (Choice B) Although bupropion is a first-line antidepressant, it can also cause insomnia, jitteriness, and anxiety. It would not be a preferred choice in a patient who has experienced activating side effects on fluoxetine. (Choice D) Phenelzine is a monoamine oxidase inhibitor that is not used as a first-line antidepressant agent due to its unfavorable side effect profile and dietary restrictions to reduce the risk of hypertensive crisis. (Choice E) Trazodone is most often used in low doses to treat insomnia as the doses required to treat depression typically result in intolerable sedation. In addition to sedation, it has a significant side effect profile, including dry mouth, orthostatic hypotension, and rarely, priapism. Educational objective: Selective serotonin reuptake inhibitors (SSRIs) are first-line antidepressants due to their generally favorable side effect profile compared to tricyclic antidepressants and monoamine oxidase inhibitors. Because certain SSRIs may be more likely to cause specific side effects (eg, insomnia), a patient who responds to an SSRI but experiences intolerable side effects may be switched to a different SSRI. References: Impact of drug tolerability on the selection of antidepressant treatment in patients with major depressive disorder. (http://www.ncbi.nlm.nih.gov/pubmed/20397586) A comparative review of escitalopram, paroxetine, and sertraline: Are they all alike? (http://www.ncbi.nlm.nih.gov/pubmed/24424469)

A 72-Year-Old Man Comes to the Office for Follow-Up