Effect of Ketamine, Amitriptyline and Their Combination on Itch

NCT06245564 | Completed DMC

• 1 other identifier: N-20230046
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Chronic itch affects approximately a fifth of the global population and is associated with substantial negative consequences for the affected individuals. Furthermore, there is a lack of efficient treat-ment options for chronic itch. Topical ketamine cream has been used successfully to relieve various forms of pain, and we hypothesize that topical ketamine relieves itch through a mechanism of action comparable to that in pain relief. The aim of this project is to evaluate the effects of ketamine both alone and in combination with amitriptyline on histaminergic and non-histaminergic itch induced by histamine and cowhage, respectively.

Conditions

Itch

Outcome Measures

Primary Outcomes (2)

• Measuring itch 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".

  Immediately after the intervention

• Measuring pain 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".

  Immediately after the intervention

Secondary Outcomes (12)

• Superficial blood perfusion

  Immediately after the intervention

• Touch Pleasantness

  Immediately after the intervention

• Mechanically evoked itch (MEI), intensity approach

  Immediately after the intervention

• Mechanically evoked itch, spatial approach

  Immediately after the intervention

• Mechanical Pain Thresholds (MPT)

  Immediately after the intervention

Study Arms (1)

Cream application

EXPERIMENTAL

This subproject will be conducted in two sessions one week apart. Each session will last approximately 3 hours. In each forearm of the participant, two 4x4 cm areas will be selected as Area of Interest (AOI). In these selected areas, the four different creams will be applied in a randomized position for 1½ hours. After the cream removal, itch will be induced using histamine in one session and cowhage in the other session (the order of histamine and cowhage will be randomized). During the application of the substances, the itch/pain elicited will be monitored for 10 minutes using a VAS (Visual analog scale). After the removal of the substances, measurements of SBP, TP, MEI, MPT, MPS, and thermal sensitivity will be conducted.

Drug: Ketamine 0.5%; Drug: Amitriptyline; Drug: ketamine + amitriptyline; Other: Vehicle; Other: Histamine; Other: Cowhage

Interventions

Ketamine 0.5% DRUG

Ketamine cream 0.5% will be applied in a 4x4 area in the forearm of each participant.

Cream application

Amitriptyline DRUG

Amitriptyline cream 1% will be applied in a 4x4 area in the forearm of each participant.

Cream application

ketamine + amitriptyline DRUG

A cream containing ketamine 0.5%, amitriptyline 1%, will be applied in a 4x4 area in the forearm of each participant.

Cream application

Vehicle OTHER

A vehicle cream will be applied in a 4x4 area in the forearm of each participant.

Cream application

Histamine OTHER

After the cream removal, itch will be induced using histamine in the first session

Cream application

Cowhage OTHER

After the cream removal, itch will be induced using cowhage in the second session

Cream application

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 history of neurological, dermatological, immunological, musculoskeletal, cardiac disorder or mental illnesses (psychiatric diagnosis) that may affect the results (e.g., neuropathy, muscular pain in the upper extremities, anxiety, depression, schizophrenia etc.)
• Moles, wounds, scars, or tattoos in the area to be treated or tested
• Current use of medications that may affect the trial such as antihistamines and pain killers.
• Participants had known allergy/discomfort to ketamine or amitriptyline
• Skin diseases
• Consumption of alcohol or painkillers 24 hours before the study days and between these
• Acute or chronic pain and itch
• Participation in other trials within 1 week of study entry (4 weeks in the case of pharmaceutical studies)
• Lack of ability to cooperate

Sponsors & Collaborators

• Aalborg University: lead

Study Sites (1)

Center for Neuroplasticity and Pain Faculty of Medicine, Aalborg University

Gistrup, Aalborg, 9260, Denmark

Location

MeSH Terms

Conditions

Pruritus

Interventions

Amitriptyline; Ketamine; Histamine

Condition Hierarchy (Ancestors)

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

Intervention Hierarchy (Ancestors)

Dibenzocycloheptenes; Benzocycloheptenes; Polycyclic Aromatic Hydrocarbons; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Polycyclic Compounds; Cyclohexanes; Cycloparaffins; Hydrocarbons, Alicyclic; Biogenic Monoamines; Biogenic Amines; Amines; Ethylamines; Imidazoles; Azoles; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Autacoids; Inflammation Mediators; Biological Factors

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Masking Details: The participant will be blinded about which cream is applied.
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Assistant Professor

Model Details: In each participant, the four different creams will be applied in a randomized position. After the cream removal, itch will be induced using histamine in one session and cowhage in the other session.

Study Record Dates

• First Submitted: January 25, 2024
• First Posted: February 7, 2024
• Study Start: August 20, 2024
• Primary Completion: December 31, 2024
• Study Completion: December 31, 2024
• Last Updated: January 30, 2025

Record last verified: 2024-10

Data Sharing

• IPD Sharing: Will not share

Locations

DK (1)