Gabapentin for the treatment of pain related to radiation-induced mucositis in patients with head and neck cancers treated with intensity modulated radiation therapy (IMRT)

16513 Background: Gabapentin has been reported to effectively treat multiple neuropathic pain syndromes. This retrospective study evaluates the efficacy of gabapentin for the treatment of pain related to radiation induced mucositis, in patients with head and neck cancers, treated with radiation therapy (RT). Methods: This retrospective study includes 30 pts with head and neck cancers, treated with RT, without concomitant or induction chemotherapy. IMRT planning was performed using a concomitant boost technique with a median dose of 54 Gy, 63 Gy, and 66 Gy delivered to the low risk clinical tumor volume (CTV), high risk CTV and boost target volume, respectively, using 30- 34 fractions. The dose of gabapentin was gradually increased starting on the second week of RT from 600 mg/day to the dose of 2700 mg/d over the course of one week. Narcotic pain medication (Roxicodone) was prescribed as needed. Results: 26 (86%) pts required no pain medication during the first two weeks of RT, despite the presence of grade 1 and/or 2 mucositis in 24 of them. During the third and fourth weeks of RT, 28 (93%) pts were treated with a median dose of 2700 mg/day of gabapentin, with only 3 (10%) pts requiring low dose narcotic pain medication, 15–30 mg/day of Roxicodone, added to gabapentin for adequate pain control, despite grade 2 or higher mucositis in 22 pts. During weeks 5 and 6, 28 (93%) pts continued to be treated with a median dose of 2700 mg/day of gabapentin with only 10 (35%) pts requiring 15–40 mg/day of Roxicodone, in addition to gabapentin for pain control, despite the presence of grade 2 or higher mucositis in 23 pts. Only 3% of the pts in this group had delay in RT delivery. Gabapentin was well tolerated with only 13% of pts experiencing mild side effects (somnolence, nausea, or vomiting), which were managed with reducing the dose or changing the dosing schedule. Conclusions: Gabapentin is effective and well-tolerated for the treatment of mucositis-induced pain related to radiation treatment in patients with head and neck cancers, treated with IMRT. We further demonstrate that the use of gabapentin at doses of 2700 mg per day can reduce or eliminate the need for narcotic pain medication. No significant financial relationships to disclose.