A Mechanistic Evaluation of the Interactions Between Thermoceptive and Pruriceptive Sensory Processing

Aalborg University

Status: Completed

Conditions: Itch; Serotonine; Thermal Stimulation; Cowhage; Histamine

Treatments: Other: Pre-heating; Other: Heat stimulation; Drug: Lidocaine; Other: Histamine; Other: Cowhage; Other: Serotonin

Study type: Interventional

Funder types: Other

Identifiers

NCT03576053

N-20180035

Details and patient eligibility

About

The purpose of this human experimental study is to evaluate the pattern of itch intensity over time in response to strong, short-term heat stimulation in two different models of histamine and cowhage-induced itch. Moreover, the purpose is to evaluate the effect of mild pre-heating of the skin in human experimental models of histamine, cowhage and serotonin. Finally, we want to investigate the effect of short-term intense heat stimulation on previously anesthetized skin.

Enrollment: 59 patients

Sex: All

Ages: 18 to 60 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Healthy men and women
• Age 18-60 years
• Able to speak and understand English

Exclusion criteria

• Suffering from chronic disease
• Pregnancy or lactation
• Prior experience of adverse effects from anaesthetic, specifically Lidocaine
• Drug addiction defined as the use of cannabis, opioids or other drugs - 5 -
• Previous neurologic, musculoskeletal or mental illnesses
• Lack of ability to cooperate
• Current use of medications that may affect the trial
• Active skin diseases
• Active participation in other experiments currently ongoing or within the last 14 days
• Tattoos on volar forearms that will interfere with local skin measurements

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Double Blind

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59 participants in 3 patient groups, including a placebo group

Histamine+cowhage+heat

Experimental group

Treatment:

Other: Heat stimulation

Other: Cowhage

Other: Histamine

Histamine+cowhage+serotonin+pre-heating

Experimental group

Treatment:

Other: Pre-heating

Other: Cowhage

Other: Serotonin

Other: Histamine

lidocaine and saline+heat

Placebo Comparator group

Treatment:

Other: Heat stimulation

Drug: Lidocaine