Effect of Prophylactic Dual Histamine Blockade on Filgrastim-Induced Bone Pain in Female Cancer Patients: Single Institutional Analysis.

Bone pain is the commonest side-effect faced by cancer patients receiving granulocyte colony stimulating factor (G-CSF) therapy for the primary or secondary prevention of febrile neutropenia. We conducted a prospective quasi-experimental study at our setup to see the efficacy of dual histamine blockade (combined H1 and H2 receptor blockers) for preventing G-CSF-induced bone pain. Adult female patients with solid tumors who had received filgrastim for the primary prophylaxis of febrile neutropenia and met our inclusion criteria, were enrolled (n = 119). This population was analyzed for the development of significant bone pain 24 h after the administration of Filgrastim. Significant bone pain in our study was defined as emergence of new onset pain measuring ≥4 on 11-point Numerical rating scale (NRS) or at least ≥ 2-point increase in score when compared to the baseline pain (if any). Those patients who experienced significant bone pain (n = 47) were given Loratadine 10 mg and Famotidine 20 mg orally half an hour before the next filgrastim administration. Pain assessment was done 24 h after Filgrastim administration, using NRS and data was analyzed. The mean NRS score in our patients after administration of filgrastim was 6.87 ± 1.055. Most of these patients (n = 34 i.e 72%) experienced relief in bone pain after dual histamine blockade use. The mean NRS score following the use of dual antihistamines was 4.36 ± 1.870. The NRS score improved by a mean of 2.51 after using dual histamine blockade, which was statistically significant (p-value= 0.0005). We propose that dualhistamine blockade may prove to be an effective option for prophylaxis of G-CSF-induced-bone-pain. Randomized control trials on larger and more diverse patient populations are required to reinforce the findings.