title: A randomized clinical trial of efficacy and safety of the topical clonidine and capsaicin in the treatment of painful diabetic neuropathy.
abstract: BACKGROUND
  Incomplete efficiency of oral medications restricts their therapeutic success in pain control of the painful form of the diabetic peripheral neuropathy (DPN). Use of topical medications because of less systemic side effects is more acceptable. This study aimed to compare the effect of clonidine gel and capsaicin cream in relieving pain associated with DPN.
  
  
  METHODS
  This 12-week, randomized, double-blind and parallel-group trial was conducted to compare the efficacy and safety of topical clonidine and capsaicin. Totally, 139 patients with type 2 diabetes with a pain score of at least 4 as assessed by visual analog scale (VAS), were treated for up to 3 months. The endpoint of the study was the reduction in the median pain score from baseline, as assessed by the VAS at the 4 weekly follow-up visits.
  
  
  RESULTS
  The intention-to-treat population for the efficacy analysis consists of 69 patients receiving clonidine and 70 patients receiving capsaicin. Both drugs significantly relieved pain at 12 weeks (P < 0.001 for both) but no significant difference in the efficacy between the two treatments was observed (P = 0.931). Dermatologic complications were more common in capsaicin group (P = 0.001).
  
  
  CONCLUSIONS
  The results of this study showed the comparable efficacy of clonidine gel in comparison with capsaicin cream in the treatment of pain due to DPN with less adverse events. More studies are required to better evaluate the efficacy and safety of this topical compound for relieving pain in DPN.
authors.affiliation: Department of Internal Medicine, Division of Endocrinology, School of Medicine, Hamedan University of Medical Sciences, Hamedan, Iran.
authors.forename: Javad
authors.initials: J
authors.lastname: Kiani
authors.affiliation: Department of Internal Medicine, School of Medicine, Hamedan University of Medical Sciences, Hamedan, Iran.
authors.forename: Firuzeh
authors.initials: F
authors.lastname: Sajedi
authors.affiliation: Department of Pharmaceutical, Cosmeceutical and Hygienic Products Formulation Lab, Center for Research and Training in Skin Diseases and Leprosy, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Saman Ahmad
authors.initials: SA
authors.lastname: Nasrollahi
authors.affiliation: Department of Community Medicine, School of Medicine, Hamedan University of Medical Sciences, Hamedan, Iran.
authors.forename: Farzaneh
authors.initials: F
authors.lastname: Esna-Ashari
keywords: Capsaicin; clonidine; efficacy; neuropathy; topical