Ethnic Differences in Response to Topical Capsaicin: A Psychophysical Study on Healthy Subjects

To comprehensively evaluate the ethnic differences in response to topical capsaicin and its effect on thermal sensory thresholds.

Inclusion criteria

• Adult men and women who are between 18 and 50 years of age.
• Subjects must be in general good health with no skin disease, disease state or physical condition which would impair evaluation of pain perception or which would increase their health risk by study participation as determined by the investigators.
• Women of childbearing potential will be required to have a negative pregnancy test in order to enroll in the study.

Exclusion criteria

• Adults over age 50.
• Children less than 18 years of age.
• Unable to complete the required measures.
• Diagnosis of diseases that would affect the measurement of pain perception.
• Currently enrolled in any investigational study in which the subject is receiving any type of drug, biologic, or non-drug therapy and subjects undergoing treatment with another investigational drug or approved therapy for investigational use within 30 days prior to study participation.
• Use of oral analgesic or other medications known to interfere with pain perception in the week prior to the study.
• Use of emollient on the forearms on the day of the study visit.
• Use of medicated topical preparations on the forearms for the week prior to the study.
• Known history of neuropathy causing diseases such as uremia.
• Known history of uncontrolled thyroid disease.
• Known history of diabetes mellitus.
• Allergy to capsaicin.
• Pregnant women.