Comparative Efficacy of Duloxetine Versus Nortriptyline in Patients with Diabetic Peripheral Neuropathic Pain: A Double Blind Randomized Controlled Trial

Background: Diabetic peripheral neuropathic pain (DPNP) is a common type of diabetic neuropathy. Blood sugar control is the first step for management of DPNP and drug treatment may be prescribed for the pain relief. Objectives: This study assessed the efficacy and safety of duloxetine and nortriptyline in patients with DPNP. Methods: This double-blind randomized clinical trial was conducted in the diabetes clinic of Golestan Hospital (Ahvaz, Iran). Convenience sampling and simple random allocation were used in the study. 134 patients with DPNP were randomly divided into two groups (67 patients in each group). The duloxetine group received 30 to 60 mg/day and nortriptyline group received 25 to 75 mg/day for a period of 6 weeks. Pain assessment was conducted based on a Visual analogue scale (VAS) and drug side effects were assessed on a weekly basis. Results: The study showed that both groups had significant reduction in pain severity at the end of the study (P < 0.05). The proportion of patients achieving 50% reduction in pain severity was significantly greater in the duloxetine group than the nortriptyline group (P < 0.05). The treatment side effects observed in the two groups were not significantly different (P = 0.298). Conclusions: Monotherapy with duloxetine and nortriptyline is safe and effective in the management of patients with DPNP.