A 78-year-old client with major depressive disorder is started on sertraline 50 mg daily. The nurse reviews the following trend data. Which response is most appropriate at each time point?

Quick answer
At 14 days, the sodium of 128 mEq/L with new confusion and orthostatic hypotension indicates clinically significant hyponatremia requiring provider notification and fall precautions. At 7 days, sodium 133 mEq/L with mild unsteadiness warrants increased sodium intake and monitoring, not immediate discontinuation. At 21 days, the worsening sodium despite fluid restriction requires escalation, not continued observation.

Why this is correct
The trend shows a progressive fall in sodium from 138 to 123 mEq/L over 21 days. At day 7, the sodium is mildly low but the client is asymptomatic except for mild unsteadiness; conservative management is appropriate. By day 14, the sodium has dropped to 128 mEq/L with new confusion and orthostatic hypotension, signaling the need for provider notification and safety measures. At day 21, sodium is 123 mEq/L with worsening gait instability and confusion despite fluid restriction, requiring urgent reassessment and likely medication adjustment.

Clinical picture
SSRI-associated hyponatremia typically develops within the first 2-4 weeks of treatment. Early symptoms include nausea, malaise, and unsteady gait. As sodium falls below 130 mEq/L, confusion, lethargy, and orthostatic hypotension may appear. Severe hyponatremia (<125 mEq/L) can lead to seizures, coma, and death. Management includes discontinuing the offending agent, fluid restriction, and slow sodium correction to avoid osmotic demyelination.

Memory hook
Remember the mnemonic 'SALT LOSS' for hyponatremia symptoms: Seizures, Altered mental status, Lethargy, Tachycardia, Low urine output, Orthostatic hypotension, Shallow respirations, Stupor.

NCLEX decision rule
For symptomatic hyponatremia with sodium <130 mEq/L, notify the provider and implement fall precautions. Do not rapidly correct sodium; aim for <10-12 mEq/L in 24 hours. Fluid restriction is first-line for euvolemic hyponatremia, but if sodium continues to fall, the SSRI may need to be discontinued.

Why the alternatives are wrong
At day 7, 'notify provider immediately' is premature because sodium is only mildly low and the client is stable. At day 14, 'encourage increased fluid intake' would worsen dilutional hyponatremia. At day 21, 'continue current plan and recheck in 1 week' is unsafe given the progressive decline and symptoms.