Evaluation of Peripheral Itch Mechanisms Following Injection of Morphine (Second Sub-Project)

NCT ID: NCT04700007

Last Updated: 2022-01-27

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 26 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2021-01-18
• Study Completion Date: 2021-12-31

Brief Summary

The aim of our 2nd sub-project is to clarify if the capsaicin receptor TRPV1 is implicated in the mechanism of morphine-induced mast cell degranulation. Moreover, we also aim to clarify if the mechanism of opioid-induced itch relay on the histaminergic pathway by using the antihistamine (diphenhydramine) to suppress the release of histamine from peripheral mast cells.

Conditions

Itch

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Study group

Group Type: EXPERIMENTAL

Capsaicin

Intervention Type: DRUG

A capsaicin patch will be applied on a 3x3 cm squared area on the volar forearm. The patch will be left in place for 24h after which it will be removed.

Diphenhydramine

Intervention Type: DRUG

Diphenhydramin cream 1% (Restamine®) will be applied on a 3x3 cm squared predetermined area on the volar forearm for 24 hours.

Morphine Chloride

Intervention Type: DRUG

Morphine solution (0.1mg/ml, Morphine Hydrochloride) 50 μl will be applied intradermally to the center of a predetermined area on the volar forearm by a 1 ml syringe.

Isotonic saline

Intervention Type: DRUG

injections of isotonic saline (0.05 ml, 0.9%) as vehicle will be performed.

Histamine

Intervention Type: DRUG

A small drop of histamine dihydrochloride (1%, in saline) will be applied to a previously determined area on the volar forearm followed by a prick through the drop.

Interventions

Capsaicin

A capsaicin patch will be applied on a 3x3 cm squared area on the volar forearm. The patch will be left in place for 24h after which it will be removed.

Intervention Type: DRUG

Diphenhydramine

Diphenhydramin cream 1% (Restamine®) will be applied on a 3x3 cm squared predetermined area on the volar forearm for 24 hours.

Intervention Type: DRUG

Morphine Chloride

Morphine solution (0.1mg/ml, Morphine Hydrochloride) 50 μl will be applied intradermally to the center of a predetermined area on the volar forearm by a 1 ml syringe.

Intervention Type: DRUG

Isotonic saline

injections of isotonic saline (0.05 ml, 0.9%) as vehicle will be performed.

Intervention Type: DRUG

Histamine

A small drop of histamine dihydrochloride (1%, in saline) will be applied to a previously determined area on the volar forearm followed by a prick through the drop.

Intervention Type: DRUG

Other Intervention Names

Antihistamine

Eligibility Criteria

Inclusion Criteria

• Healthy men and women
• 18-60 years
• Speak and understand English

Exclusion Criteria

• Participants with any clinically significant abnormalities that in the opinion of the investigator may increase the risk associated with trial participation or may interfere with the interpretation of the trial results.
• Pregnancy or lactation
• Drug addiction defined as any use of cannabis, opioids or other addictive drugs
• 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.
• Participants with known allergy/discomfort to the opioid morphine and antihistamine.
• Skin diseases
• Moles, scars or tattoos in the area to be treated or tested.
• 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)

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 60 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Aalborg University

OTHER

Sponsor Role: lead

Responsible Party

Silvia Lo Vecchio

PhD, Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Locations

Mech-Sense, Medicinsk Gastroenterologisk ambulatorium, Medicineshus, Aalborn Universitethospitalet

Aalborg, North Denmark, Denmark

Countries

Denmark

Other Identifiers

N-20200084 2nd sub-project

Identifier Type: -

Identifier Source: org_study_id