Clinical trial NCT04635254: The Effect of Halophyte-based Cream on Pain and Itch
Official title: Effects of Halophyte-based Cream Skin Application in a Human Experimental Model of Pain and Itch
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Pain, Acute
Itch
Lead sponsor: Aalborg University
Sponsor class: OTHER
First posted: 2020-11-19
Enrollment: 32
Sex: ALL
Minimum age (years): 18
Maximum age (years): 60
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: In this study the investigators wish to investigate whether halophyte-based cream applied to the skin can reduce itch applied by means of small needles from the plant mucuna pruriens (also called cowhage) or by histamine (an itch-evoking substance formed in the human body). Further, the investigators wishes to investigate whether long-term application of halophyte-based cream has a pain-relieving effect on heat/cold and pinprick stimulations.

Detailed description: Salt-tolerant plants (also called halophytes) can grow in saline soil or directly in salt water (e.g. along coasts). For centuries, these plants have been used in folk medicine, and among other things they are believed to have pain-relieving and anti-inflammatory effect.

Even though experiments have already investigated halophytes as a pain relieving substance, the mechanisms in relation to pain and/or itch are still unknown. Therefore, the investigators wish to investigate whether halophyte-based cream applied to the skin can reduce itch applied by means of small needles from the plant mucuna pruriens (also called cowhage) or by histamine (an itch-evoking substance formed in the human body). Further, the investigators wishes to investigate whether long-term application of halophyte-based cream has a pain-relieving effect on heat/cold and pinprick stimulations.

Eligibility criteria: Inclusion Criteria:

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

Exclusion Criteria:

* Pregnancy or lactation
* Drug addiction defined as any use of cannabis, opioids or other drugs
* Previous or current neurologic, musculoskeletal or mental illnesses that may affect the results (e.g. neuropathy, muscular pain in the upper extremities, etc.)
* Lack of ability to cooperate
* Current use of medications that may affect the trial such as antihistamine medications or pain killers
* Skin diseases
* 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)

Primary outcomes:
measure: Superficial blood perfusion
timeFrame: Day 0
measure: Superficial blood perfusion
timeFrame: 24 hours after cream application
measure: Superficial blood perfusion
timeFrame: 48 hours after cream application
measure: Itch intensity
timeFrame: Day 0
measure: Itch intensity
timeFrame: 24 hours after cream application
measure: Itch intensity
timeFrame: 48 hours after cream application
measure: Pain intensity
timeFrame: Day 0
measure: Pain intensity
timeFrame: 24 hours after cream application
measure: Pain intensity
timeFrame: 48 hours after cream application
measure: Measuring Alloknesis
timeFrame: Day 0
measure: Measuring Alloknesis
timeFrame: 24 hours after cream application
measure: Measuring Alloknesis
timeFrame: 48 hours after cream application
measure: Trans-epidermal Water Loss (TEWL)
timeFrame: Day 0
measure: Trans-epidermal Water Loss (TEWL)
timeFrame: 24 hours after cream application
measure: Trans-epidermal Water Loss (TEWL)
timeFrame: 48 hours after cream application
Secondary outcomes:
measure: Measurement of Warm Detection Thresholds (WDT)
timeFrame: Day 0
measure: Measurement of Warm Detection Thresholds (WDT)
timeFrame: 24 hours after cream application
measure: Measurement of Warm Detection Thresholds (WDT)
timeFrame: 48 hours after cream application
measure: Measurement of Cold Detection Thresholds (CDT)
timeFrame: Day 0
measure: Measurement of Cold Detection Thresholds (CDT)
timeFrame: 24 hours after cream application
measure: Measurement of Cold Detection Thresholds (CDT)
timeFrame: 48 hours after cream application
measure: Measurement of Heat Pain Thresholds (HPT)
timeFrame: Day 0
measure: Measurement of Heat Pain Thresholds (HPT)
timeFrame: 24 hours after cream application
measure: Measurement of Heat Pain Thresholds (HPT)
timeFrame: 48 hours after cream application
measure: Measurement of Cold Pain Thresholds (CPT)
timeFrame: Day 0
measure: Measurement of Cold Pain Thresholds (CPT)
timeFrame: 24 hours after cream application
measure: Measurement of Cold Pain Thresholds (CPT)
timeFrame: 48 hours after cream application
measure: Measurement of Pain to Supra-threshold Heat Stimuli:
timeFrame: Day 0
measure: Measurement of Pain to Supra-threshold Heat Stimuli:
timeFrame: 24 hours after cream application
measure: Measurement of Pain to Supra-threshold Heat Stimuli:
timeFrame: 48 hours after cream application
measure: Measurement of Mechanical Pain Thresholds (MPT)
timeFrame: Day 0
measure: Measurement of Mechanical Pain Thresholds (MPT)
timeFrame: 24 hours after cream application
measure: Measurement of Mechanical Pain Thresholds (MPT)
timeFrame: 48 hours after cream application
measure: Measurement of Mechanical Pain Sensitivity (MPS)
timeFrame: Day 0
measure: Measurement of Mechanical Pain Sensitivity (MPS)
timeFrame: 24 hours after cream application
measure: Measurement of Mechanical Pain Sensitivity (MPS)
timeFrame: 48 hours after cream application
Other outcomes:
Locations:
city: Aalborg
country: Denmark
facility: Aalborg University
Study officials:
References: