None listed
Conditions
Brief summary
The study is investigating the sensations that people feel when different menthol or capsaicin gel is placed on their skin over a 15-minute time frame and whether the onset of these sensations occurs more quickly when the skin is pretreated with microneedles (tiny needles that push a very short distance into the skin). We hypothesise that the microneedles will increase permeation of the applied drugs across the skin giving faster and more intense sensations.
Interventions
60 pain-free subjects (18-65), voluntarily by poster / Curtin radio adverts
Separate study for menthol and capsaicin (30 subjects in each)
Menthol gel protocol:
Repeated measures design:
1.Microneedle pretreatment or dummy procedure will be applied to test area on forearm of the volunteer. Microneedle pretreatment involves pressing the microneedle array firmly onto the skin for a 10 second period. Microneedles have recently become commercially available, for example with the 3M MicrochannelTM S
60 pain-free subjects (18-65), voluntarily by poster / Curtin radio adverts Separate study for menthol and capsaicin (30 subjects in each) Menthol gel protocol: Repeated measures design: 1.Microneedle pretreatment or dummy procedure will be applied to test area on forearm of the volunteer. Microneedle pretreatment involves pressing the microneedle array firmly onto the skin for a 10 second period. Microneedles have recently become commercially available, for example with the 3M MicrochannelTM Skin System (3M, St Paul, MN). This comprises an array of pyramidal-shaped needles approximately 700 micrometer in height with tip-to-tip needle spacing of approximately 500 micrometer that penetrate 100-150 micrometer into the epidermis. The microneedle pretreatment or dummy procedure will be applied to the skin with each volunteer receiving both treatment and dummy procedure over the two test days. Drug gel treatment will be the same on each test day. Dummy microneedles look the same as the microneedle array but the points of the needles have been blunted so that they do not penetrate the skin. 2.TiVi measurement of skin colour (erythema) will be recorded prior to and immediately after microneedle pretreatment 3.Two grams of 15% menthol in a hydroalcoholic gel will then be applied and occluded by a Tegaderm dressing for a total period of 15 minutes. 4.The gel will be wiped off the skin with a damp cloth and the area dried gently 5.TiVi measurements will be resumed for 15 min following removal of the gel. The approximate duration of each session is 30 mins, washout period is 7 days. The protocol above will be repeated for 2g of 0.025% capsaicin in a hydroalcoholic gel.
Sponsors
Curtin University
Study design
Allocation
Non-randomised trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject)
Eligibility
Sex/Gender
All
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
healthy skin, without any underlying comorbidities, or known allergies to menthol or capsaicin.
Exclusion criteria
history of asthma, allergic rhinitis or atopy, or skin irritation with topical products containing menthol or capsaicin, or allergic skin reactions to topical substances; broken skin or recent tattoo at the treatment site. The previous topical menthol study suggested that the anti-acne drug Roaccutane may amplify response to menthol so is now also an exclusion criteria. Subjects’ forearm skin will be checked for redness or signs of reaction between applications and subjects allowed to withdraw from further test sessions if a significant skin irritation lasts longer than 2 hours (visual or sensory effect). Note that the gels will be applied under occlusion therefore risk of inhalation of menthol or capsaicin is reduced.
Outcome results
None listed