MedPath

Investigation of a New Human Model for Itch

Not Applicable
Completed
Conditions
Itch
Interventions
Other: Papain
Other: Histamine
Other: Cowhage
Other: L-menthol
Registration Number
NCT04711044
Lead Sponsor
Aalborg University
Brief Summary

This third sub-project aims to evaluate the interaction between the TRPM8 receptor and pruritus by studying the anti-pruritic effect of TPRM8-agonist L-menthol on histaminergic and non-histaminergic itch induced using three different pruritogens: histamine, cowhage and papain.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
20
Inclusion Criteria
  • Healthy men and women
  • 18-60 years
  • Speak and understand English
Exclusion Criteria
  • Pregnancy or lactation
  • Drug addiction defined as any use of cannabis, opioids or other addictive drugs
  • Previous or current history of neurological, dermatological, immunological musculoskeletal, cardiac disorder or mental illnesses that may affect the results (e.g. neuropathy, muscular pain in the upper extremities, etc.).
  • Lack of ability to cooperate
  • Current use of medications that may affect the trial such as antihistamines, antipsychotics and pain killers, as well as systemic or topical steroids.
  • Skin diseases
  • Moles, scars or tattoos in the area to be treated or tested.
  • Hypersensitivity to papaya and mango fruit, cashew nuts, rubber latex
  • Consumption of alcohol or painkillers 24 hours before the study days and between these
  • Acute or chronic pain
  • Participation in other trials within 1 week of study entry (4 weeks in the case of pharmaceutical trials)

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Study groupHistamine-
Study groupPapain-
Study groupCowhage-
Study groupL-menthol-
Primary Outcome Measures
NameTimeMethod
Measuring Alloknesis15 minutes

Alloknesis is measured by using mildly pruritic, non-painful von Frey nylon filaments of a predetermined intensity (generally 5-30 milliNewton of force).

Measuring itch intensity by computerized Visual Analog Scale ScoringFor 15 minutes

We will ask the subjects to rate the sensation of itch on a 100 mm VAS scale ranging from 0 to 100 where 0 indicates "no itch" and 100 indicates "worst itch imaginable

Measuring pain intensity by computerized Visual Analog Scale ScoringFor 15 minutes

We will ask the subjects to rate the sensation of pain on a 100 mm VAS scale ranging from 0 to 100 where 0 indicates "no pain" and 100 indicates "worst pain imaginable".

Superficial blood perfusion measurementAfter 15 minutes

Superficial blood perfusion is measured by a Speckle contrast imager

Secondary Outcome Measures
NameTimeMethod
Measurement of Heat Pain Thresholds (HPT)15 minutes

The tests for thermal sensation will all be conducted using a PATHWAY ATS (Medoc Ltd, Israel) thermal sensory testing device.

Measurement of Mechanical Pain Sensitivity (MPS)15 minutes

This test is conducted using a pin-prick set.

Touch Pleasantness (TP)15 minutes

Pleasant touch sensation measured using a standardized sensory brush

Measurement of Cold PainThresholds (CPT)15 minutes

The tests for thermal sensation will all be conducted using a PATHWAY ATS (Medoc Ltd, Israel) thermal sensory testing device.

Measurement of Cold Detection Thresholds (CDT)15 minutes

The tests for thermal sensation will all be conducted using a PATHWAY ATS (Medoc Ltd, Israel) thermal sensory testing device.

Measurement of Pain to Supra-threshold Heat Stimuli15 minutes

The tests for thermal sensation will all be conducted using a PATHWAY ATS (Medoc Ltd, Israel) thermal sensory testing device.

Measurement of Warm Detection Thresholds (WDT)15 minutes

The tests for thermal sensation will all be conducted using a PATHWAY ATS (Medoc Ltd, Israel) thermal sensory testing device.

Measurement of Mechanical Pain Thresholds (MPT)15 minutes

This test is conducted using a pin-prick set.

Trial Locations

Locations (1)

Aalborg University

🇩🇰

Aalborg, Nordjylland, Denmark

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