Inhibition of Non-histaminergic Pruritus Applied Using 3 Different Pruritogens

NCT04858360 | Completed DMC

• 1 other identifier: N-20200073 1st sub-project
• Study Type: interventional
• Target: 22
• Locations: 1 country
• Sites: 1

Brief Summary

With this experiment, we want to use to investigate whether repeated application of EMLA cream as a tool to modulate non-histaminergic itching, which is produced using small needles from the plant mucuna pruriens (it is known that antihistamine does not attenuate this form of itch) and we want to compare the effect of short (1 hour) and prolonged (3 hours) application of EMLA. The sub-project takes place in 3 sessions over a period of 3 consecutive days (24 hours apart). All sessions will be identical.

Conditions

Itch

Outcome Measures

Primary Outcomes (11)

• Measuring itch intensity by computerized Visual Analog Scale Scoring

  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

  For 9 minutes

• Measuring pain intensity by computerized Visual Analog Scale Scoring

  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".

  For 9 minutes

• Superficial blood perfusion measurement

  Superficial blood perfusion is measured by a Speckle contrast imager

  After 1 hour

• Superficial blood perfusion measurement

  Superficial blood perfusion is measured by a Speckle contrast imager

  After 3 hours

• Superficial blood perfusion measurement

  Superficial blood perfusion is measured by a Speckle contrast imager

  10 min after cowhage application

• Measuring Alloknesis

  Alloknesis sensation is measured using a standardized sensory brush exerting a force of 200 to 400 mN.

  After 1 hour

• Measuring Alloknesis

  Alloknesis sensation is measured using a standardized sensory brush exerting a force of 200 to 400 mN.

  After 3 hours

• Measuring Alloknesis

  Alloknesis sensation is measured using a standardized sensory brush exerting a force of 200 to 400 mN.

  10 min after cowhage application

• Measuring Hyperknesis

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

  After 1 hour

• Measuring Hyperknesis

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

  After 3 hours

• Measuring Hyperknesis

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

  10 min after cowhage application

Secondary Outcomes (6)

• Measuring Erythema

  After 1 hour

• Measuring Erythema

  After 3 hours

• Measuring Erythema

  10 min after cowhage application

• Measuring Skin Pigmentation

  After 1 hour

• Measuring Skin Pigmentation

  After 3 hours

Study Arms (1)

Study group

EXPERIMENTAL

Drug: Emla 1 hour; Drug: EMLA 3 hours; Other: Vehicle cream for 1 hour; Other: Vehicle cream for 3 hours; Other: Cowhage

Interventions

Emla 1 hour DRUG

At the start of each session, the middle forearms of the subject will each be divided into two squared areas (4x4 cm). On each arm, the two areas will be located 4 cm apart. Then one area will be pre-treated with cutaneous 2.5% lidocaine/2.5% prilocaine cream (EMLA cream) for 1 hour.

Study group

EMLA 3 hours DRUG

At the start of each session, the middle forearms of the subject will each be divided into two squared areas (4x4 cm). On each arm, the two areas will be located 4 cm apart. Then one area will be pre-treated with cutaneous 2.5% lidocaine/2.5% prilocaine cream (EMLA cream) for 3 hours.

Study group

Vehicle cream for 1 hour OTHER

At the start of each session, the middle forearms of the subject will each be divided into two squared areas (4x4 cm). On each arm, the two areas will be located 4 cm apart. Then two area will be pre-treated with a vehicle cream for 1 h.

Study group

Vehicle cream for 3 hours OTHER

At the start of each session, the middle forearms of the subject will each be divided into two squared areas (4x4 cm). On each arm, the two areas will be located 4 cm apart. Then two area will be pre-treated with a vehicle cream for 3 h.

Study group

Cowhage OTHER

Cowhage spicules are 1-2 mm in length and have a diameter of 1-3 μm. The spicules are inserted by gently rubbing 30-35 spicules into a 1 cm diameter skin area.

Study group

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Healthy men and women
• years
• Speak and understand English

You may not qualify if:

• Pregnancy or lactation
• Drug addiction defined as any use of cannabis, opioids or other drugs
• Previous or current neurologic, musculoskeletal 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 antihistamine medications or pain killers.
• Skin diseases
• Hypersensitivity to papaya and mango fruit, cashew nuts and 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)
• Known history of anaphylactic shock, or local allergy (contact dermatitis) to lidocaine, prilocaine or other local anaesthetics of the amide type.

Sponsors & Collaborators

• Aalborg University: lead

Study Sites (1)

Aalborg University

Aalborg, 9220, Denmark

Location

MeSH Terms

Conditions

Pruritus

Interventions

Lidocaine, Prilocaine Drug Combination

Condition Hierarchy (Ancestors)

Skin Diseases; Skin and Connective Tissue Diseases; Skin Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Lidocaine; Acetanilides; Anilides; Amides; Organic Chemicals; Prilocaine; Aniline Compounds; Amines; Drug Combinations; Pharmaceutical Preparations

Study Officials

• Silvia lo Vecchio

  Aalborg University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: PhD, Assistant Professor

Study Record Dates

• First Submitted: April 21, 2021
• First Posted: April 26, 2021
• Study Start: November 15, 2021
• Primary Completion: August 1, 2022
• Study Completion: October 1, 2022
• Last Updated: January 18, 2023

Record last verified: 2023-01

Locations

DK (1)