Health TrialsbyHealthPanel

Mechanisms Underlying the Placebo Effect in Both Histaminergic and Non-histaminergic Itch

ConditionITCH
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age18-60
SponsorAalborg University

About this trial

The study consists of one experimental session of approximately 1½ hours. The participant will fill in a series of questionnaires about how you perceive itch and pain, and about some traits of your personality, such as depression, anxiety and stress. Afterwards, two areas will be selected on each forearm of the subjects. The four areas will be treated with the same vehicle cream for 20 minutes, in order to test the placebo effect. At the end of the cream application, two areas will be randomly treated with histamine while cowhage will be applied on the other two areas. During the 10 minutes of the application of the pruritogens, itch and pain will be continuously monitored using a Visual Analog Scale.

Eligibility criteria

This trial accepts healthy volunteers

Qualifiers

Healthy men and women

18-60 years

Speak and understand English

Disqualifiers

Pregnancy or lactation

Drug addiction defined as any use of cannabis, opioids, or other drugs

Previous or current history of neurological, immunological, musculoskeletal, cardiac disorder or psychiatric diagnoses 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

Trial design

Design model

Single group

Treatments tested in this trial

  • Histamine

    Other intervention

    To deliver histamine, standard allergy skin prick test (SPT) lancets are applied

  • Cowhage

    Other intervention

    The spicules will be manually inserted. Approximately 30-35 spicules are gently rubbed into a 1 cm diameter skin area on the forearm/face

Treatment groups

30 Participants
are divided into 1 treatment group
Group A: PlaceboExperimental treatment 2 interventions

Trial outcomes

Primary outcomes

1

Measuring pain by computerized Visual Analog Scale Scoring

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

Time frame
Immediately after the intervention
2

Measuring itch by computerized Visual Analog Scale Scoring

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

Time frame
Immediately after the intervention

Secondary outcomes

1

Pain Catastrophizing Scale (PCS).

The PCS assesses negative and exaggerated coping concerning anticipated or experienced painful stimuli. Thirteen items have to be answered on a 5-point Likert-type scale ranging from 0 (Not at all) to 4 (all the time).

Time frame
Baseline
2

Itch Catastrophizing Scale (ICS).

The ICS assesses negative and exaggerated coping concerning anticipated or experienced itchy stimuli. Thirteen items have to be answered on a 5-point Likert-type scale ranging from 0 (Not at all) to 4 (all the time).

Time frame
Baseline
3

Learned Helplessness Scale (LHS)

The questionnaire consists of 20 items, and the participant's response to each item is rated on a 4-point Likert scale ranging from strongly agree (1) to strongly disagree (4).

Time frame
Baseline
4

Depression, Anxiety, Stress Scale (DASS-21)

The questionnaire measures the magnitude of depression, anxiety, and stress. Each of these three subscales consists of 7 questions answered using a 0-3 Likert scale, with 0 meaning "it did not apply to me", and 3 meaning "it applied to me very much"

Time frame
Baseline

Other outcomes

Sponsors and contacts

Click on the lead sponsor to view all of their trials.

Aalborg University

Lead sponsor

Source ClinicalTrials.gov
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