We are updating the design of this site. Learn more.
Show more
ClinicalTrials.gov
ClinicalTrials.gov Menu

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

This study has been completed.
Sponsor:
ClinicalTrials.gov Identifier:
NCT00655811
First Posted: April 10, 2008
Last Update Posted: November 8, 2017
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by (Responsible Party):
Wake Forest University Health Sciences ( Wake Forest University )
  Purpose
The purpose of this research is to study how people respond differently to capsaicin in different racial groups and the effect it has on your pain levels. Capsaicin is a natural product made from hot chili peppers that is useful for treating the itch symptoms of skin disease.

Condition Intervention Phase
Healthy Drug: Capsaicin Drug: Placebo moisturizing cream Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Ethnic Differences in Response to Topical Capsaicin: A Psychophysical Study on Healthy Subjects

Resource links provided by NLM:


Further study details as provided by Wake Forest University Health Sciences ( Wake Forest University ):

Primary Outcome Measures:
  • Ethnic Differences in Burning Pain Induced by Topical Capsaicin [ Time Frame: 1 day ]
    The primary endpoint is to test the burning pain effect of topical capsaicin by using an continuous visual analog scale (CoVAS) intensity scale as an outcome measure. Participants will rate burning pain intensity after topical capsaicin application. The burning or pain sensation intensity was recorded continuously on a 100-mm COVAS (0, no sensation to 100, maximum, strongest imaginable pain sensation). The subjects were also asked to indicate whether they experienced any nonpainful sensation.


Secondary Outcome Measures:
  • Ethnic Differences on the Effects of Topical Capsaicin on Thermal Sensory Thermal Thresholds [ Time Frame: 1 day ]
    A secondary endpoint is to see if topical capsaicin has an effect on warm and heat pain thresholds. Quantitative thermosensory testing was carried out using the Medoc TSA 2001 (Medoc Ltd). The probe baseline temperature was 32 °C and the contact area was 12 cm2. The probe warmed the skin surface at a linear rate of 0·4 °C per second, up to a cut-off of 50 °C. Thermal thresholds were measured in the following order: warmth sensation threshold was measured followed by heat pain detection threshold; each of them was determined four times by the ascending method of limits.

  • The Difference in Burning/Pain Sensation Ratings Between the Capsaicin or Placebo Application. [ Time Frame: 1 day ]
    This secondary outcome is to see if subjects rated burning/pain differently between the topical capsaicin or placebo application. Participants will rate burning/pain intensity after topical capsaicin and placebo application. The burning/pain sensation intensity was recorded continuously on a 100-mm COVAS (0, no sensation to 100, maximum, strongest imaginable burning/pain sensation). The subjects were also asked to indicate whether they experienced any non-burning/-painful sensation.


Enrollment: 40
Study Start Date: February 2008
Study Completion Date: October 2009
Primary Completion Date: August 2008 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Capsaicin
Capsaicin 0.1% cream application to the volar side of forearm.
Drug: Capsaicin
Topical application, 0.1%, Capzasin HP; Chattem Inc., Chattanooga, TN, U.S.A
Other Name: Topical capsaicin, 0.1%, Capzasin HP
Placebo Comparator: Placebo moisturizing cream
Placebo moisturizing cream with no active ingredient (Cetaphil; Galderma Laboratories LP, Fort Worth, TX, U.S.A.) to the opposite forearm.
Drug: Placebo moisturizing cream
Placebo moisturizing cream with no active ingredient (Cetaphil; Galderma Laboratories LP, Fort Worth, TX, U.S.A.)
Other Name: Cetaphil

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

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


Ages Eligible for Study:   18 Years to 50 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

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.
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00655811


Locations
United States, North Carolina
Wake Forest University Health Sciences Dermatology
Winston-Salem, North Carolina, United States, 27157
Sponsors and Collaborators
Wake Forest University
Investigators
Principal Investigator: Gil Yosipovitch, MD Wake Forest University Health Sciences
  More Information

Responsible Party: Wake Forest University
ClinicalTrials.gov Identifier: NCT00655811     History of Changes
Other Study ID Numbers: 00003739
First Submitted: April 4, 2008
First Posted: April 10, 2008
Results First Submitted: March 16, 2017
Results First Posted: August 14, 2017
Last Update Posted: November 8, 2017
Last Verified: August 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Keywords provided by Wake Forest University Health Sciences ( Wake Forest University ):
Healthy volunteers

Additional relevant MeSH terms:
Capsaicin
Antipruritics
Dermatologic Agents
Sensory System Agents
Peripheral Nervous System Agents
Physiological Effects of Drugs