Optimal Antidepressant for Elderly Woman Discontinuing Venlafaxine Due to Hyponatremia

Rationale for Mirtazapine

Mirtazapine demonstrates superior efficacy for insomnia compared to other second-generation antidepressants, with limited evidence showing improvement in sleep scores over fluoxetine and venlafaxine, according to the American College of Physicians, 1, 2
All second-generation antidepressants show equivalent efficacy for treating severe depression in elderly patients, so the choice should be guided by side effect profile and comorbid symptoms, as recommended by the American College of Physicians, 1, 2

Trazodone shows improvement in sleep scores over venlafaxine and is associated with higher somnolence than other antidepressants, which may benefit insomnia, as noted by the American Academy of Sleep Medicine, 2
Bupropion has significantly lower rates of sexual dysfunction compared to SSRIs and may provide benefit for fatigue given its activating properties, according to the American College of Physicians, 1, 2

Paroxetine and fluoxetine should be avoided in elderly patients due to higher rates of adverse effects, as recommended by the American Academy of Family Physicians, 4

The American Academy of Sleep Medicine recommends starting mirtazapine at 7.5-15 mg at bedtime in elderly patients, 3
Lower doses of mirtazapine (7.5-15 mg) are often more sedating than higher doses due to antihistamine effects, as noted by the American Academy of Sleep Medicine, 3
Weight gain is a notable side effect of mirtazapine, but may be acceptable given patient's other priorities, according to the American College of Physicians, 1, 2