Heat-, Cold-, and Mechanical Pain Thresholds Under Exposition of High Dose Topical Capsaicin
试验速览
- 阶段
- 4 期
- 状态
- 已完成
- 入组人数
- 20
- 试验地点
- 1
- 主要终点
- Heat pain threshold (HPT) in degrees Celsius (°C)
研究概览
简要总结
Aim of the study is to determine heat pain thresholds (HPT in °C) and cold pain thresholds (CPT in °C) during topical capsaicin 8% application, and mechanical pain thresholds (MPT in g) immediately after to find out the exact skin temperature by which capsaicin initiates the application pain (heat pain threshold, HPT in °C) but also the temperature by which capsaicin does not yet trigger a cold pain (cold pain threshold, CPT in °C). Moreover the investigators want to find out the mechanical pain threshold in g from topical capsaicin and to verify a prolonged effect of capsaicin on the pain thresholds.
详细描述
Capsaicin is the main pungent ingredient in chili peppers. Topical capsaicin 8% is used for the treatment of peripheral neuropathic pain. Application of capsaicin 8% provokes distinct pain by activating the transient receptor potential vanilloid 1 (TRPV1) receptor. Cooling the skin results in a reliable prevention of the application pain. However, the necessary cooling temperature and if cooling itself produces application pain, is unknown.
Materials and Methods
10 female and 10 male healthy volunteers will be enrolled in a randomised, double blind, placebo controlled, cross-over study. The left or right forearm of each subject is going to be treated with a capsaicin 8% patch (QUTENZA, Astellas Pharma, Tokyo, Japan) of 9 cm² or a placebo patch (Demo patch, Astellas Pharma, Tokyo, Japan) of the same size for 60 min. Then the other forearm (which has not been tested before) will be treated with the remaining patch. During capsaicin and placebo exposure HPT in °C and CPT in °C are going to be obtained by the thermode of a thermal sensory analyser, TSA-II (Medoc Ltd., Ramat Yishai, Israel). Temperature increase/decrease of the thermode will be stopped, as soon as the subject presses a switch because of a beginning pain sensation. Immediately after exposure a pin prick test will be performed 5 times in a row by pressing a Mini-Spike (B. Braun Melsungen AG, Melsungen, Germany) slowly against the skin of the application areal to determine the pressure necessary to provoke a sharp pain (Mechanical pain threshold in g). 2 weeks later HPT, CPT, and MPT will be determined again in the areas of capsaicin and placebo exhibition.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Crossover
- 主要目的
- Prevention
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •healthy volunteers 18 ore more years old
排除标准
- •dermatologic or neurologic injuries on both thighs, (possible) pregnancy
研究组 & 干预措施
Capsaicin
Treatment with Topical High dose Capsaicin
干预措施: Topical High dose Capsaicin (Drug)
Placebo
Treatment with Topical Placebo
干预措施: Topical Placebo (Drug)
结局指标
主要结局
Heat pain threshold (HPT) in degrees Celsius (°C)
时间窗: 60 minutes during topical highdose Capsaicin/Placebo exposure
During capsaicin and placebo exposure HPT in degrees Celsius (°C) is determined by a thermal sensory analyser TSA-II (Medoc Ltd.)
次要结局
- Cold pain threshold (CPT) in degrees Celsius (°C)(60 minutes during topical highdose Capsaicin/Placebo exposure)
- Mechanical pain threshold (MPT) in grams (g)(Immediately after topical highdose Capsaicin/Placebo exposure)
- HPT in degrees Celsius (°C)(2 weeks after exposure)
- MPT in grams (g)(2 weeks after exposure)
- CPT in degrees Celsius (°C)(2 weeks after exposure)
研究者
E. Knolle, MD
Ao.Univ.-Prof. Dr. Erich Knolle
Medical University of Vienna