HistamineNCT06328530
Itch Sensation Induced by Simultaneous Application of Pruritogens (Spatial Summation)
A study testing Cowhage and Histamine in people with Histamine and Cowhage, run by Aalborg University at 1 site in Denmark.
Trial summary
In This experiment, the investigators would like to design a new itch model based on the spatial summation of pruritic stimuli. The hypothesis behind this study (spatial summation) is that two simultaneous applications of pruritogens will result in higher itch sensation compared with a single application of pruritogen. Read more about this study
- Who is it for?
- Ages 18 to 60 yearsHealthy volunteers can take part
- What is being tested?
- Cowhage and Histamine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 24 participants
- Where
- 1 siteDenmark
- Study dates
- 1 Apr 2024to 31 Dec 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 60 years
- All sexes
- Healthy volunteers accepted
- Adult
Who may be able to join
- Healthy men and women
- 18-60 years
- Speak and understand English
Who cannot join
- Pregnancy or lactation
- Drug addiction defined as any use of cannabis, opioids, or other addictive drugs
- Previous or current history of neurological (e.g. neuropathy), immunological (e.g. asthma, immune deficiencies, arthritis) musculoskeletal (e.g. muscular pain in the upper extremities,), cardiac disorder, or mental illnesses that may affect the results
- 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
- Skin diseases (e.g. atopic dermatitis, pruritus nodularis, eczema, psoriasis)
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- 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 one week of study entry (four weeks in the case of pharmaceutical trials)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Denmark1 site, 1 recruiting
- Recruiting
Aalborg University
Aalborg, 9620
Silvia Lo Vecchio, +4521397785, slv@hst.aau.dk
About this study
Official title: Repetitive Applications of Pruritogens and Effects of a Cutaneous-induced Pain Stimulation on Nonhistaminergic Itch Perception
In This experiment, the investigators would like to design a new itch model based on the spatial summation of pruritic stimuli. The hypothesis behind this study (spatial summation) is that two simultaneous applications of pruritogens will result in higher itch sensation compared with a single application of pruritogen.
Read the detailed description
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 treatment options for chronic itch. In order to mimic a clinical itch condition as presented in patients, the aim of the project is to investigate a new itch model based on the spatial summation of pruritic stimuli. The aim of this experiment is to assess the itch sensation induced by simultaneous application of pruritogens (spatial summation). In particular, the purpose is to evaluate if a single application of cowhage/histamine (non-histaminergic and histaminergic itch respectively) results in a lower itch sensation compared to two simultaneous applications of the pruritogens, on the same arm or in different arms.
- Being tested
- Cowhage, Histamine
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
CowhageOther
25 spicules will be inserted in the center of the predefined skin area on the mandibular area. The spicules will be gently rubbed for 15-20 seconds in circular motion to facilitate epidermal penetration.
HistamineOther
Histaminergic itch will be evoked by a 1% histamine solution. A droplet of histamine solution will be placed on the predetermined area on the forearm, and the SPT lancet will be pierced through the histamine with 120 g of pressure for 1-2 seconds.
| Study group | Role | What they receive |
|---|---|---|
| 1st pruritogen | Experimental | The subproject consists of 2 sessions 3 days apart. Each session consists of 3 parts.
In the first session, 3 test areas (4x4 cm) will be selected on the subject's forearms. In part 1, we will apply cowhage in one area. In part 2, we will apply cowhage in two areas on the same arm. In part 3, we will again apply cowhage in 2 areas, one on each arm. In each part, the itch intensity will be measured using a VAS (visual analog scale) for 10 min from the cowhage application. After removal of the cowhage, alloknesis and mechanically evoked itch will be measured in the area selected in part 1. Receives: Other: Cowhage |
| 2nd pruritogen | Other | The second session will take place 3 days after the first one and will follow the same procedure as session 1. However, histamine will be applied instead of cowhage. The order of the two sessions will be randomized. Receives: Other: Histamine |
What is being measured
The primary outcome is the main question the study is designed to answer.
Assessment of itch
Immediately following the itch provocations, participants will be instructed to rate the itch intensity for 10 minutes using a digital visual analogue scale (VAS; eVAS Software: Aalborg, University, Denmark), on a tablet. The scale will be measured from 0 to 100, where 0 represents 'no itch' and 100 'worst itch imaginable'.
Measured: 1 minute after every itch inductions
Assessment of pain
Immediately following the itch provocations, participants will be instructed to rate the pain intensity for 10 minutes using a digital visual analogue scale (VAS; eVAS Software: Aalborg, University, Denmark), on a tablet. The scale will be measured from 0 to 100, where 0 represents 'no pain' and 100 'worst pain imaginable'.
Measured: 1 minute after every itch inductions
Secondary outcomes (2)
Alloknesis
Alloknesis sensation is measured using a standardized sensory brush (SENSELab Brush-05, Somedic AB, Hörby, Sweden) exerting a force of 200 to 400 mN.
Measured: 12 minutes after every itch inductions
Mechanically evoked itch
Mechanically evoked itch is measured using three von Frey filaments of 4.08, 4.16 and 4.31 (1.0, 1.4, 2.0 g, respectively) (North Coast Medical, Gilroy, CA). The center of the skin area is stimulated by 3 pricks, repeated 3 times in short succession. After a total of 9 stimulations, the participants will report the itch elicited on a numerical rating scale (NRS) from 0 to 10 (0 = "no itch"; 10 = "worst imaginable itch").
Measured: 15 minutes after every itch inductions
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Mar 2024
- Study start1 Apr 2024
- Primary completion31 Dec 2025 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HistamineStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Single group
- Model description
- The participants will randomly receive applications of cowhage and histamine.
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 24 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Aalborg University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Silvia Lo Vecchio, Aalborg University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06328530
- Sponsor's protocol ID
- N-20210046 3rd project
- Status last verified
- May 2024
- First submitted
- 19 Mar 2024
- Last updated
- 6 May 2024
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 6 May 2024. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Repetitive Applications of Pruritogens and Effects of a Cutaneous-induced Pain Stimulation on Nonhistaminergic Itch Perception
- ClinicalTrials.gov ID
- NCT06328530
- Acronym / sponsor ID
- N-20210046 3rd project
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 24 participants (estimated)
- Lead sponsor
- Aalborg UniversityUniversity, hospital or other
- Study start
- 1 Apr 2024 (actual)
- Primary completion
- 31 Dec 2025 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 25 Mar 2024 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
In This experiment, the investigators would like to design a new itch model based on the spatial summation of pruritic stimuli. The hypothesis behind this study (spatial summation) is that two simultaneous applications of pruritogens will result in higher itch sensation compared with a single application of pruritogen.
Detailed description
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 treatment options for chronic itch. In order to mimic a clinical itch condition as presented in patients, the aim of the project is to investigate a new itch model based on the spatial summation of pruritic stimuli. The aim of this experiment is to assess the itch sensation induced by simultaneous application of pruritogens (spatial summation). In particular, the purpose is to evaluate if a single application of cowhage/histamine (non-histaminergic and histaminergic itch respectively) results in a lower itch sensation compared to two simultaneous applications of the pruritogens, on the same arm or in different arms.
Study design
- Primary purpose
- Basic science
- Allocation
- Randomised
- Intervention model
- Single group
- Masking
- Single blind (participant)
- Number of arms
- 2
- Model description
- The participants will randomly receive applications of cowhage and histamine.
| Arm | Type | Receives |
|---|---|---|
| 1st pruritogen | Experimental | Other: CowhageThe subproject consists of 2 sessions 3 days apart. Each session consists of 3 parts. In the first session, 3 test areas (4x4 cm) will be selected on the subject's forearms. In part 1, we will apply cowhage in one area. In part 2, we will apply cowhage in two areas on the same arm. In part 3, we will again apply cowhage in 2 areas, one on each arm. In each part, the itch intensity will be measured using a VAS (visual analog scale) for 10 min from the cowhage application. After removal of the cowhage, alloknesis and mechanically evoked itch will be measured in the area selected in part 1. |
| 2nd pruritogen | Other | Other: HistamineThe second session will take place 3 days after the first one and will follow the same procedure as session 1. However, histamine will be applied instead of cowhage. The order of the two sessions will be randomized. |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
Key inclusion criteria (3 listed)
- Healthy men and women
- 18-60 years
- Speak and understand English
Key exclusion criteria (10 listed)
- Pregnancy or lactation
- Drug addiction defined as any use of cannabis, opioids, or other addictive drugs
- Previous or current history of neurological (e.g. neuropathy), immunological (e.g. asthma, immune deficiencies, arthritis) musculoskeletal (e.g. muscular pain in the upper extremities,), cardiac disorder, or mental illnesses that may affect the results
- 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
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Cowhage25 spicules will be inserted in the center of the predefined skin area on the mandibular area. The spicules will be gently rubbed for 15-20 seconds in circular motion to facilitate epidermal penetration. | Other | 1st pruritogen |
| HistamineHistaminergic itch will be evoked by a 1% histamine solution. A droplet of histamine solution will be placed on the predetermined area on the forearm, and the SPT lancet will be pierced through the histamine with 120 g of pressure for 1-2 seconds. | Other | 2nd pruritogen |
Primary outcome
Assessment of itch
Time frame: 1 minute after every itch inductions
Immediately following the itch provocations, participants will be instructed to rate the itch intensity for 10 minutes using a digital visual analogue scale (VAS; eVAS Software: Aalborg, University, Denmark), on a tablet. The scale will be measured from 0 to 100, where 0 represents 'no itch' and 100 'worst itch imaginable'.
Assessment of pain
Time frame: 1 minute after every itch inductions
Immediately following the itch provocations, participants will be instructed to rate the pain intensity for 10 minutes using a digital visual analogue scale (VAS; eVAS Software: Aalborg, University, Denmark), on a tablet. The scale will be measured from 0 to 100, where 0 represents 'no pain' and 100 'worst pain imaginable'.
2 secondary outcomes
Alloknesis
Time frame: 12 minutes after every itch inductions
Mechanically evoked itch
Time frame: 15 minutes after every itch inductions
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 May 2024.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Cowhage and Histamine in people with Histamine and Cowhage, run by Aalborg University at 1 site in Denmark.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 3 inclusion and 10 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 6 May 2024. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Denmark. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Silvia Lo Vecchio, PhD (+4521397785, slv@hst.aau.dk), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Assessment of itch (time frame: 1 minute after every itch inductions). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 May 2024; AzTrials last refreshed its copy on 6 Nov 2026.