A client receiving pembrolizumab for melanoma develops worsening fatigue, hypotension, hyponatremia, and low cortisol. Which is the nurse's priority interpretation?

• 1 Immune-related adverse event (irAE) — likely hypophysitis or primary adrenal insufficiency; hold pembrolizumab, start stress-dose hydrocortisone, endocrine workup ✓ Correct answer
• 2 Sepsis secondary to immunotherapy-related immunosuppression; obtain cultures, start broad-spectrum antibiotics, give IV fluids, and continue pembrolizumab for cancer control.
• 3 Symptoms unrelated to pembrolizumab therapy; likely due to progressive melanoma with adrenal metastases, manage with supportive care and continue immunotherapy.
• 4 Hypovolemia from poor oral intake causing hyponatremia and hypotension; administer intravenous normal saline boluses, monitor electrolytes, and resume pembrolizumab when stable.

For study reference only. Always follow current clinical guidelines and your institution’s protocols.