Mazzocato, C., Buclin, T., & Rapin, C.H. (1999). The effects of morphine on dyspnea and ventilatory function in elderly patients with advanced cancer: A randomized double-blind controlled trial. Annals of Oncology, 10(12), 1511–1514.doi: 10.1023/A:1008337624200
Subcutaneous (SC) morphine 5 mg or placebo in opioid-naïve patients and regular oral morphine dose plus half of the every-four-hour (q4h) dose given SC in patients on regularly scheduled opioids
The study was conducted in an inpatient geriatric hospital.
The study was a double-blind, placebo controlled, randomized, cross-over trial.
Intermittent injections of morphine at the doses used reduce cancer-related dyspnea. The changes in respiratory effort and rate but not anxiety support the theory that the benefit of morphine is unlikely related to somnolence or an effect on anxiety.