A 52-year-old woman with chronic low back pain has been on morphine 60 mg daily (long-acting formulation) for 6 months with good pain control. She now presents with acute severe pain (VAS 8/10) following a fall, and her usual long-acting morphine is no longer providing adequate relief. Her respiratory rate is 18/min, SpO₂ 97% on room air, and she is alert and oriented. Which statement best describes the appropriate management of her acute pain exacerbation?