Quick answerTreat this as
symptomatic escitalopram-associated hyponatremia.
Why this is correctSSRIs can cause SIADH, especially in older adults. Headache, confusion, and a fall with sodium 124 mEq/L require the suspected drug to be held, prompt evaluation, fall and seizure precautions as indicated, and serial sodium monitoring.
Easy analogy or mental pictureToo much antidiuretic effect traps free water and dilutes sodium; remove the trigger and correct slowly under monitoring.
Memory hookNew SSRI plus confusion: check sodium.NCLEX decision ruleFor a new medication followed by a dangerous laboratory change and neurologic symptoms, hold the suspect agent and escalate rather than treating the symptom alone.
Why the other choices are wrongFree water can worsen dilutional hyponatremia, dose escalation increases exposure, and rapid unprescribed correction can cause serious neurologic harm.
References
1DailyMed: EscitalopramSIADH, symptomatic hyponatremia, and older-adult risk