title: Thiamine, cobalamin, locally injected alone or combination for herpetic itching: a single-center randomized controlled trial.
abstract: OBJECTIVE
  The present study was designed to explore the efficacy of locally injected thiamine or cobalamin in relieving itch or pain and improving the daily living activities among patients with herpetic itching.
  
  
  METHODS
  Eighty eligible patients with herpetic itching with a worst itching score of ≥ 4 were randomized to receive locally injected thiamine (B1 group), cobalamin (B12 group), lidocaine (LD group), or combination of thiamine and cobalamin (COB group) for 4 weeks. The treatment efficacy was assessed based on the patients' pruritus and pain severity, global impression of change, and activities of daily living and quality of life.
  
  
  RESULTS
  After 7 days, thiamine yielded a significant itch relief, cobalamin yielded a significant pain relief, and their combination significantly relieved both pain and itch; which all continued till the endpoint (all Ps<0.001). However, lidocaine did not provide significant itch or pain relief than the other groups. Sixteen patients in the thiamine group achieved ≥ 30% itch reduction; 18 patients in the cobalamin group obtained ≥ 30% pain reduction; and 18 patients achieved ≥ 30% itch reduction and 19 patients obtained ≥ 30% pain reduction in the combination group. The activities of daily living and quality of life data at the endpoint were consistent with a significant benefit in the thiamine (P<0.05), cobalamin, and combination groups (both Ps<0.001).
  
  
  CONCLUSIONS
  Locally injected thiamine had a significant antipruritic effect, cobalamin had an analgesic effect, and their combination had the dual effect with no obvious synergies. This intervention was efficacious, tolerable, and safe for herpetic itching.
authors.affiliation: Department of Rehabilitation Medicine, Affiliated Tenth People's Hospital of Tongji University, Shanghai, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Xu
authors.forename: Zhong-Wei
authors.initials: ZW
authors.lastname: Lv
authors.forename: Gang Xiao
authors.initials: GX
authors.lastname: Xu
authors.forename: Wei-Zhen
authors.initials: WZ
authors.lastname: Tang
mesh_terms: D000203:Activities of Daily Living; D000779:Anesthetics, Local / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D005260:Female; D006562:Herpes Zoster / Q000150:complications*; D006801:Humans; D008012:Lidocaine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology; D010147:Pain Measurement; D011537:Pruritus / Q000175:diagnosis / Q000188:drug therapy* / Q000209:etiology; D011788:Quality of Life; D012720:Severity of Illness Index; D013831:Thiamine / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D013997:Time Factors; D016896:Treatment Outcome; D014805:Vitamin B 12 / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use
chemical_list: D000779:Anesthetics, Local; D000894:Anti-Inflammatory Agents, Non-Steroidal; D008012:Lidocaine; D014805:Vitamin B 12; D013831:Thiamine