The incidence of bone pain with granulocyte colony stimulating factor (G-CSF) administration and the effect of hydroxyzine

8242 Background: The bone pain frequently emerges as one of the side effects of G-CSF administration. Rising pressure within bone marrow by increased granulocytes, edema within bone marrow by histamine release, and increased level of bradykinin are thought to be the mechanisms underlying it. The incidence of bone pain is reported to be 1–5% of all cases, but in practice we have the impression that there have been more cases with bone pain, some of which are resistant to treatment with non-steroid anti-inflammatory drugs (NSAIDs). So we reexamined the incidence of bone pain with G-CSF and the analgesic effect of hydroxyzine. Methods: 1) We sent out questionnaires about the presence of bone pain and its details to patients who are administered G-CSF in the past and analyzed those answers, retrospectively. 2) Prospectively since 2003, we administered NSAIDs or hydroxyzine (50mg b.i.d.) to patients with bone pain after G-CSF administration and examined its analgesic effect. With next G-CSF administration in t...