Gabapentin Monotherapy for the Treatment of Chemotherapy-Induced Neuropathic Pain: A Pilot Study

ABSTRACT Objective. This study was conducted to investigate the efficacy and safety of gabapentin monotherapy in the management of chemotherapy‐induced neuropathic pain. Patients. Seventy‐five cancer patients who had previously received chemotherapy, and had experienced at least one symptom of neuropathic pain were included in the intervention group. They received a fixed low‐dose of gabapentin (800 mg/day). The control group consisted of 35 cancer patients with similar treatment history and symptomatology, who refused treatment with gabapentin and, therefore, received a fixed‐dose combination of naproxen and codeine/paracetamol. Outcome Measures. Patients were grouped in three categories according to the severity of their neuropathic symptoms at baseline: mild, moderate, and severe. Analgesic efficacy of the study drug was assessed by means of a patient‐answered questionnaire. Four stages of analgesic response were established: complete, partial, minor, and no response. Results. All patients completed the study and were evaluable. In the intervention arm, gabapentin led to a complete response in 25.3% of patients (19/75), partial response in 44% (33/75), minor response in 25.3% (19/75), and no response in 5.3% (4/75). The response to gabapentin correlated with the severity of the underlying neurotoxicity. Approximately 25% of patients receiving gabapentin experienced mild somnolence, but none discontinued it. In the control group, none experienced complete response (0/35), while partial, minor, and no response were observed in 5.7% (2/35), 45.7% (16/35), and 48.6% (17/35), respectively. Compared with the control group, gabapentin therapy led to a statistically significant better response in patients of each baseline neurotoxicity group. Conclusions. Gabapentin monotherapy seems to be well tolerated and useful for the management of chemotherapy‐induced neuropathic pain.