Safety studies

Subject selection: Criteria for inclusion
  • Subjects were over 18 years of age
  • Male or female subjects of any skin type or race
  • Subjects gave their written informed consent
  • Subjects were in good health, free of any significant active skin pathology
Subject selection: Criteria for exclusion
  • History of known sensitivity to cosmetics in general and in particular to the types of products being tested
  • Pregnant or likely to be pregnant during the study period
  • Lactating
  • Prescription drug used within 30 days of study commencement – corticosteroids, antihistamines which may tend to attenuate reactions
Performed at Midwest clinical trials

A Bioscreen company
CA 90503

Participants enrolled
completing the study
completing the study
Age rangeNo of subjectsPercentage of study population
Test materials and procedure
  • The test material was applied occlusively, 0.1% w/w diluted in petrolatum
  • 0.2 g or 0.2 cc of the test material was dispensed onto the skin of the upper back
  • Paper tape such as 3M Micropore or Kendall Tenderskin™ was used for fixation after preparation of the surrounding skin with an adhesion enhancer such as Mastisol™
  • The subject was instructed to avoid exposure to water or to direct sunlight during the 48 hour observation period and evaluated by trained personnel under the supervision of the principal investigator (dermatologist)
  • Reactions were scored based on the appearance of erythema or edema immediately following the removal of the patch
  • Subjects were instructed to report any delayed reactions occurring after the final reading
Results and conclusions
  • No erythema or edema was observed in any of the subjects after 48 hours exposure of the skin to the test material
  • The test material, when tested as described under 48 hour occlusive patch testing on fifty subjects, appears not to produce primary (contact) irritation. Therefore Tetrahydropiperine has low skin irritation potential