IRCT201108287432N1 IRCT 2012-01-12 Kermanshah University of Medical Sciences The comparative study of combination Gabapentin and topiramate vs treatment alone topiramate or Gabapentin of painful diabetic neuropathy The comparative study of combination Gabapentin and topiramate vs treatment alone topiramate or Gabapentin of painful diabetic neuropathy 2011-11-16 anticipated 150 Complete https://irct.ir/trial/7889 interventional Randomization: Randomized, Blinding: Single blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment. N/A Diabetic neuropathy. Intervention 1: In second group, gabapentin started by 300 mg/daily and like the first groups are examined. Intervention 2: In first group, treatment started with 50mg/daily topiramate and patients visited respectively at day 15, 30, 60 and 90 and drug dose increases based on treatment response and patient tolerance if necessary, respectively, 100, 200, and maximize 400 mg. Intervention 3: The third group combination of 25mg topiramate and 100mg gabapentin will start and on the basis of response to treatment and patient tolerance the dose will increased.