title: Slow injection of nefopam reduces pain intensity associated with intravenous injection: a prospective randomized trial.
abstract: OBJECTIVE
  We aimed to investigate the frequency and severity of pain associated with intravenous injection of nefopam and to determine whether a slow rate of administration can effectively reduce such pain.
  
  
  METHODS
  We used a solution containing 30 mg nefopam diluted to 20 ml in saline. In all, 102 adult patients undergoing minor surgery were randomly allocated to one of three administration groups: A (60 ml/h, n = 34); B (120 ml/h, n = 34); or C (180 ml/h, n = 34). All patients scored the maximal pain experienced during the 120-s infusion period, using the visual analogue scale (VAS) and the verbal pain score (VPS). Adverse events including phlebitis were recorded.
  
  
  RESULTS
  Eighty-three patients (29 in group A, 27 each in groups B and C) were included in the final analysis. The incidence of injection pain was lower in group A (86.2 %) than in groups B (96.3 %) and C (100 %), but this difference was not statistically significant. The proportion of patients with a tolerable level of pain (VAS 0-3 and VPS 0-1) was significantly higher in group A (79.3 %) versus groups B (7.4 %) and C (3.7 %). The mean VAS scores for groups A, B, and C were 2.2 ± 1.3, 5.1 ± 1.6, and 7.2 ± 1.7, respectively, and these differences were statistically significant.
  
  
  CONCLUSIONS
  At the slower rate of infusion (60 ml/h) of the 1.5 mg/ml nefopam solution, injection pain intensity was attenuated to a significantly greater degree than at the faster rates.
authors.affiliation: Department of Anesthesiology and Pain Medicine, Guro Hospital, Korea University, College of Medicine, 148 Gurodong-ro, Guro-gu, Seoul, Korea.
authors.forename: Young Min
authors.initials: YM
authors.lastname: Kim
authors.forename: Byung Gun
authors.initials: BG
authors.lastname: Lim
authors.forename: Heezoo
authors.initials: H
authors.lastname: Kim
authors.forename: Myoung Hoon
authors.initials: MH
authors.lastname: Kong
authors.forename: Mi Kyoung
authors.initials: MK
authors.lastname: Lee
authors.forename: Il Ok
authors.initials: IO
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D009340:Nefopam / Q000008:administration & dosage / Q000627:therapeutic use*; D010146:Pain / Q000188:drug therapy*; D010147:Pain Measurement
chemical_list: D018712:Analgesics, Non-Narcotic; D009340:Nefopam