Local Changes of Skin Characteristics After an Application of a Topical Product With a Warming or Cooling Effect
Condition: Healthy
Study type: Interventional

Summary: 
      The use of topical over-the-counter (OTC) products with a warming or cooling effect is
      widespread in the fields of sport, physiotherapy and in private households. Advertisements
      for such products promise pain relief when suffering from musculoskeletal disorders such as
      muscle tension, rheumatism or acute injuries, e.g. sprains. In literature, there are only
      little information about the efficacy and the physiological mechanisms of topical warming or
      cooling products. Therefore, the aim of this study is to investigate the local skin
      characteristics during and after an application of a topical product with a warming or
      cooling effect.
    

Detailed description: 
      The use of topical products for local pain relief in chronic or acute musculoskeletal
      disorders is widely used. Despite the widespread use of these products, there is missing
      information on the physiological mechanisms and efficacy of topical warming and cooling
      ointments. Most of the existing literature is about the efficacy of topical non-steroidal
      anti-inflammatory drug (NSAID)-products on chronic pain in osteoarthritis. Furthermore, one
      study tested the cooling effect of gels with different menthol concentrations. They found
      that, regardless of the concentration, the skin temperature was reduced up to one hour post
      application in the area of application.

      The aim of our study is to evaluate the change of skin characteristics after a single
      application of a warming or cooling topical product on healthy subjects. Outcome parameters
      include skin perfusion, temperature, skin redness and subjective thermal sensation. We only
      selected products in form of alcohol based ointments, menthol or wintergreen oil. Sprays and
      patches were excluded.

      The application area is the unilateral lumbar back region, whereas the contralateral side
      serves as control area. After an acclimatization period, baseline measurements are performed,
      followed by standardized application of the topical product. The local skin responses are
      measured in 10 mins time increments up to one hour.
    

Intervention name(s): Axanova hot gel; Axanova activ gel; Perskindol Dolo Gel; Perskindol Classic Gel; Perskindol Cool Kühl-Gel; Dolor-X Hot Gel; Dolor-X Classic Gel; Dolor-X Cool Gel
Intervention type(s): Other; Other; Other; Other; Other; Other; Other; Other
Intervention description(s): Axanova hot gel is a topical product with a warming effect. It contains menthol, pine needle oil, wintergreen oil, rosemary oil, eucalyptus oil, incense oil.; Axanova activ gel is a topical product with a revulsive effect. It contains menthol, pine needle oil, orange oil, lemon oil, wintergreen oil, glycosaminoglycans.; Perskindol Dolo Gel is a topical product with a warming effect. It contains wintergreen oil, pine needle oil, aromatics, excipients.; Perskindol Classic Gel is a topical product with a revulsive effect. It contains menthol, wintergreen oil, pine needle oil, lemon oil, orange peel oil, lemon bergamot oil, rosemary oil, lavender oil, excipients.; Perskindol Cool Kühl-Gel is a topical product with a cooling effect. It contains levomenthol, color E131, aromatics, excipients.; Dolor-X Hot Gel is a topical product with a warming effect. It contains isopropyl alcohol, water, menthol, hyprolose, camphor, trometamol, paprika, wintergreen oil, excipients.; Dolor-X Classic Gel is a revulsive product. It contains water, isopropyl alcohol, menthol, spruce, hyprolose, trometamol, wintergreen oil, excipients.; Dolor-X Cool Gel is a cooling product. It contains water, isopropyl alcohol, menthol, trometamol, color E131, excipients.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Basic Science
Keywords: local skin responses; hyperemia; thermal sensation; topical warming ointments; topical cooling ointments; skin perfusion; subjective thermal sensation; muscle tissue oxygenation; skin temperature; skin redness; erythema