Effect of Melatonin on the Daytime Sleepiness side-effect of Gabapentin in Patients With Neuropathic Pain

Patients suffering from “neuropathic pain” and planed to receive gabapentin therapy will be included in the study. The patients will be randomly divided into two groups based on a software program; group 1 (melatonin +/receive melatonin) and group 2 (melatonin -/receive placebo). All patients will receive oral gabapentin therapy (Neurontin®, Pfizer, Turkey) as day 1, 300 mg; day 2, 600 mg (300 mg two times per day); day 3, 900 mg (300 mg, three times per day) and 900 mg (300 mg, three times per day) thereafter. Patients in group 1 (melatonin +) will receive 3 mg melatonin (Melatonina®, Interpharm, Turkey) orally 60 minutes before bedtime starting from the first day of gabapentin therapy While patients in group 2 (placebo) will receive matching placebo capsules 60 min before bedtime. Melatonin therapy will continue for 30 days while gabapentin therapy will last for 3 months. A calendar with two boxes for each study drug under each day, will be given to all of the patients. The patients will be asked to fill in the related boxes if they remember to take their drugs on that day. The calendars will be checked on 10th and 30th days to monitor adherence to the therapy.