title: Strontium nitrate decreased histamine-induced itch magnitude and duration in man.
abstract: BACKGROUND
  Previous studies have demonstrated that strontium salts have a potent and broad ability to suppress sensory irritation.
  
  
  OBJECTIVE
  To ascertain the possible antipruritic effects of topical strontium salts, we conducted a double-blind randomized study to evaluate the effect of 20% strontium nitrate on itch magnitude (intensity) and duration.
  
  
  METHODS
  In 8 human subjects, strontium nitrate was applied to the volar forearm and vehicle control to the contralateral volar forearm for 30 min; both substances were reapplied for an additional 5 min. Itch was then experimentally induced by intradermal injection of histamine. Itch magnitude was rated each minute for the first 20 min using a visual analogue scale (VAS). Itch duration in minutes was also recorded.
  
  
  RESULTS
  Strontium nitrate, in comparison to its vehicle control, significantly shortened itch duration from 28.1+/-5.4 min (mean +/- SEM) to 18.5+/-4.2 min (p<0.01) and reduced itch magnitude at time points 12-20 min and overall (p<0.05).
  
  
  CONCLUSIONS
  Strontium nitrate may act as a topical antipruritic agent in reducing histamine-mediated itch.
authors.affiliation: Department of Dermatology, School of Medicine, University of California, San Francisco, Calif. 94143-0989, USA.
authors.forename: H
authors.initials: H
authors.lastname: Zhai
authors.forename: W
authors.initials: W
authors.lastname: Hannon
authors.forename: G S
authors.initials: GS
authors.lastname: Hahn
authors.forename: R A
authors.initials: RA
authors.lastname: Harper
authors.forename: A
authors.initials: A
authors.lastname: Pelosi
authors.forename: H I
authors.initials: HI
authors.lastname: Maibach
mesh_terms: D000328:Adult; D000982:Antipruritics / Q000627:therapeutic use; D004311:Double-Blind Method; D005260:Female; D006632:Histamine / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000627:therapeutic use*; D011537:Pruritus / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D012720:Severity of Illness Index; D012867:Skin / Q000187:drug effects / Q000473:pathology; D013324:Strontium / Q000627:therapeutic use*; D013997:Time Factors
chemical_list: D000982:Antipruritics; D009566:Nitrates; D006632:Histamine; C104873:strontium nitrate; D013324:Strontium