2016 年 42 巻 9 号 p. 605-612
The Japanese Society for Palliative Medicine has published a Clinical Practice Guideline for cancer pain management. In this Guideline, high-dose acetaminophen (2.4-4.0 g/day) is recommended to treat cancer pain. However, the effect of acetaminophen at different high doses on cancer patients has not been reported in Japan. This study was conducted to retrospectively investigate the effects of different high doses of acetaminophen on patients with cancer pain who were treated, as well as on the hepatic toxicity. Patients were divided into three groups who received acetaminophen at 2.4 g/day (n = 45), 3.2 g/day (n = 46), and 4.0 g/day (n = 20), respectively. Pain was scored according to the numeric rating scale (NRS). No significant differences were observed between the 2.4 g group, 3.2 g group and 4.0 g group regarding the incidence of Grade 2/3 hepatic toxicity (4.4% vs 4.3% vs 5.0%, respectively; P = 0.993). In contrast, significant differences in the NRS score were observed before and after acetaminophen administration in the 3.2 g group (n = 18) and 4.0 g group (n = 9), but not in the 2.4 g group (n = 16). The mean difference in the NRS score was 2.11 (P = 0.001) in the 3.2 g group, 1.56 (P = 0.028) in the 4.0 g group, and 0.44 (P = 0.297) in the 2.4 g group, respectively. In this research, acetaminophen administration at the dose of 3.2, 4.0 g a day was effective for the treatment of cancer pain.