Anti-histamines Promote Electroacupuncture Analgesia: Basic and Clinical Research

Study Overview
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Brief Summary
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Acupuncture has been used in traditional Chinese medicine for around 3,000 years and is increasingly practiced worldwide. The effects of acupuncture in chronic pain have been investigated in many clinical trials. Histamine H1 receptor antagonists are commonly used for treating allergy. Recently, investigators found that histamine H1 receptor antagonists at relatively low doses facilitate EA analgesia in the acetic acid-induced abdominal writhing test. Investigators aim to further explore whether histamine H1 receptor antagonists also facilitate EA analgesia in humans.The aims of the proposed studies are to: Conduct a clinical trial to demonstrate that H1 receptor antagonists at relatively low doses facilitate EA analgesia in healthy volunteers. This study will recruit 40 healthy normal subjects (aged between 20 and 30 years) who will be randomly assigned to one of four groups: (1) Sham acupuncture (Shallow needling without electrical stimulation) at ST36 and GB34; (2) EA at ST36 and GB34; (3) EA at ST36 and GB34 plus low-dose chlorpheniramine (2 mg); (4) EA at ST36 and GB34 plus regular-dose chlorpheniramine (4 mg). The primary endpoint will be the pain threshold. It is expected that the completion of this proposed study will enhance our knowledge as to how acupuncture analgesia can be promoted by antihistamine drugs given at a low dose and help to define its application for clinical use.

Official Title
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Anti-histamines Promote Electroacupuncture Analgesia: Basic and Clinical Research

Conditions
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Pain

Intervention / Treatment
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* Device: electroacupuncture
* Drug: antihistamine(low dose) chlorpheniramine (Dexchlorpheniramine maleate)
* Drug: antihistamine(high dose) chlorpheniramine (Dexchlorpheniramine maleate)
* Device: acupuncture


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: . Age: 20 to 30 years of age. . Agrees to undergo a comprehensive medical history and physical examination. . No history of analgesic, sedative, dietary/appetite medication intake for more than 3 weeks prior to enrolment. Exclusion Criteria: . An ongoing medical condition that requires active medical intervention or monitoring to avert serious danger to the participant's health or well-being (e.g., hypertension, diabetes mellitus, or epilepsy). . A compromised skin barrier (e.g., skin disease, allergy) that would interfere with the conduct of the EA procedure and assessments of the study. . An implant such as a pacemaker, defibrillator, or electronic medical equipment. . Pregnancy, or planning for pregnancy.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 30 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: sham EA group<br>Minimal needling at ST36 and GB34 (n=10) | Device: acupuncture<br>* Minimal needling at ST36 and GB34<br>* Other names: shallow needling;|
| Experimental: true EA group<br>EA at ST36 and GB34 (n=10) | Device: electroacupuncture<br>* Group 2 (n=10) EA at ST36 and GB34;intensity (2 mA), pulse width (1 ms), frequency (2 Hz)<br>|
| Active Comparator: EA+antihistamine(low dose) group<br>EA at ST36 and GB34 plus low-dose chlorpheniramine( Dexchlorpheniramine maleate 2mg/tab, 1 tab; n=10) | Device: electroacupuncture<br>* Group 2 (n=10) EA at ST36 and GB34;intensity (2 mA), pulse width (1 ms), frequency (2 Hz)<br>Drug: antihistamine(low dose) chlorpheniramine (Dexchlorpheniramine maleate)<br>* Group 3 (n=10) EA at ST36 and GB34 plus chlorpheniramine (Dexchlorpheniramine maleate 2mg/tab, 1 tab);intensity (2 mA), pulse width (1 ms), frequency (2 Hz)<br>* Other names: chlorpheniramine (Dexchlorpheniramine maleate 2mg/tab, 1 tab);|
| Active Comparator: EA+antihistamine(high dose) group<br>EA at ST36 and GB34 plus high-dose chlorpheniramine (Dexchlorpheniramine maleate 2mg/tab, 2 tabs; n=10) | Device: electroacupuncture<br>* Group 2 (n=10) EA at ST36 and GB34;intensity (2 mA), pulse width (1 ms), frequency (2 Hz)<br>Drug: antihistamine(high dose) chlorpheniramine (Dexchlorpheniramine maleate)<br>* Group 4 (n=10) EA at ST36 and GB34 plus chlorpheniramine (Dexchlorpheniramine maleate2mg/tab, 2 tabs);intensity (2 mA), pulse width (1 ms), frequency (2 Hz)<br>* Other names: chlorpheniramine (Dexchlorpheniramine maleate2mg/tab, 2 tabs);|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| pain threshold in each group:the current intensity of Transcutaneous electrical stimulation (TCES) | Transcutaneous electrical stimulation (TCES) is used as a method of inducing pain in the study. The procedure is to attach two electrode patches on the inside of the upper arm of the subject and then connect the electric stimulator. The current intensity will gradually increase from 0 mA, and each time increase 0.5amps until the subject feels pain in the visual analogy. Transcutaneous electrical stimulation (TCES) will be stopped at the visual analog scale of 5 (that means the moderate pain). The current intensity will be compared within and between each group. | baseline and 10min after treatment | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Electroacupuncture (EA), Antihistamine, Pain