title: Development of a novel method for quantitative evaluation of sensory skin irritation inhibitors.
abstract: OBJECTIVE
  Sensory skin irritation is regarded as one of the most serious side effects of cosmetic use. Thus, it is desirable to develop good inhibitors of sensory skin irritation. However, it is difficult to quantify the effect of sensory skin irritation inhibitors.
  
  
  METHODS
  We investigated the possibility of using an electrical current perception threshold (CPT) measurement for the quantitative evaluation of these inhibitors. We divided study populations into stinger and non-stinger groups based on their response to 5% lactic acid and assessed CPT values at 2000, 250, and 5 Hz on the cheek. Stingers showed significantly lower CPT values than non-stingers did at 250 and 5 Hz. We also measured CPT values before and after the application of nine materials with inhibitory effects on sensory skin irritation. To investigate the relationship between the change in CPT values and the effect of each material in the clinical stinging test, we conducted the stinging test with the test materials in a 5% lactic acid solution and with a 5% lactic acid solution (positive control).
  
  
  RESULTS
  There was a positive correlation between the change in CPT values and the inhibitory effect that each material had on the stinging test.
  
  
  CONCLUSIONS
  The change in CPT values can be used for the quantitative evaluation of sensory skin irritation inhibitors .
authors.affiliation: AmorePacific Corporation R&D Center, Skin Research Institute, Gyeonggi-do, Korea. eylee@amorepacific.com
authors.forename: Eunyoung
authors.initials: E
authors.lastname: Lee
authors.forename: Susun
authors.initials: S
authors.lastname: An
authors.forename: Tae Ryong
authors.initials: TR
authors.lastname: Lee
authors.forename: Han Kon
authors.initials: HK
authors.lastname: Kim
mesh_terms: D000328:Adult; D003879:Dermatologic Agents / Q000008:administration & dosage; D016903:Drug Monitoring / Q000295:instrumentation / Q000379:methods; D004558:Electric Stimulation; D005145:Face; D005260:Female; D006801:Humans; D007509:Irritants / Q000009:adverse effects*; D019344:Lactic Acid / Q000009:adverse effects; D008297:Male; D008954:Models, Biological; D010147:Pain Measurement / Q000295:instrumentation* / Q000379:methods*; D017288:Pain Threshold / Q000187:drug effects*; D012867:Skin / Q000187:drug effects; D012882:Skin Tests / Q000379:methods*; D013324:Strontium / Q000009:adverse effects; D055815:Young Adult
chemical_list: D003879:Dermatologic Agents; D007509:Irritants; D019344:Lactic Acid; C025700:strontium chloride; D013324:Strontium