Purpose: The primary aim of this study was to clarify the effect of sublingual scopolamine on the intensity of nausea.
Patients and methods: This was an open uncontrolled study, and the study participants were cancer patients consecutively admitted to a palliative care unit in Japan. When the patients had nausea, they were administered a solution of scopolamine at 0.15 mg sublingually. The intensities of nausea were assessed using the 6-point Numerical Rating Scale (NRS 0 = no nausea to 5 = worst nausea) before and 15, 30, and 60 min after administration. Primary endpoints were (1) changes in the NRS of nausea and (2) percentage of patients who achieved a decrease in NRS of 1 or more points 15 min after treatment.
Results: Twenty-six patients were recruited for this study. The median NRS significantly decreased from 3.0 (range, 1-5) to 1.5 (0-5) after 15 min, and 84 % (n = 21) of the patients achieved a decrease in NRS of 1 or more points after 15 min. In addition, the median NRS significantly decreased from 3.0 (before) to 0 (30 min) and 0 (60 min). The percentage of patients who achieved a decrease in NRS over 1 point was 96 % (n = 25) in 30 min and 100 % (n = 26) in 60 min. Fifteen percent (n = 4) showed drowsiness. No other adverse effects were reported.
Conclusion: Sublingually administered scopolamine may be effective for managing nausea in terminally ill cancer patients. Randomized controlled trials are promising.