Spinal and Supra-Spinal Pain Mechanisms in Patients With Fibromyalgia

University of Florida

Status and phase: Completed; Phase 2

Conditions: Fibromyalgia; Pain

Treatments: Other: Vehicle Patch; Drug: Capsaicin Patch 8% or 0.1% Capsaicin Cream

Study type: Observational

Funder types: Other

Identifiers

NCT03464292

OCR17639 (Other Identifier)

IRB201800479

Details and patient eligibility

About

Fibromyalgia (FM) patients have increased windup (WU). However, WU of FM patients is only quantitatively but not qualitatively different from healthy controls (HC). Thus WU abnormalities of FM patients could be the result of supra-spinal and not the result of spinal pain mechanisms. The study team will test this hypothesis by sensitizing FM patients with topical capsaicin.

Full description

The study team hypothesizes that at baseline the slopes of sensitivity adjusted WU of FM patients are not statistically different from HC. However, after capsaicin application, the slopes of sensitivity adjusted WU will be significantly different from baseline and greater than those of HC, suggesting central sensitization. This would imply that FM patients are sensitive to heat pain but not sensitized.

Enrollment: 55 patients

Sex: All

Ages: 18 to 65 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• individuals diagnosed with fibromyalgia will have pain of duration > 6 months and meeting the 1990 Research Diagnostic Criteria for FM (ACR).
• healthy, pain-free age matched controls without chronic pain

Exclusion criteria

• Allergy to red chili peppers;
• Pregnant;
• Significant hearing loss;
• Presence of chronic disease (e.g. cancer, cardiovascular disease, liver disease, kidney disease, diabetes, etc.).
• FM patients must be willing to discontinue or hold their FM related medications for at least 5 half-lives.

Trial design

55 participants in 2 patient groups

Vehicle Patch

Description:

Control patch will be the same topical solution but will not contain capsaicin. The patch will applied to the hand for 30 - 60 min. Patients will be instructed to not touch or wash their hands during the course of the study to minimize spreading of the patch to other areas of the body. Subsequently, the patch will be immediately removed.

Treatment:

Other: Vehicle Patch

Capsaicin Patch 8% or 0.1% Capsaicin Cream

Description:

8% capsaicin topical patch or 0.1% capsaicin cream. The patch will applied to the hand for 30 - 60 min. The cream will be applied similarly on a 3 cm2 area of the arm. Patients will be instructed to not touch or wash their hands during the course of the study to minimize spreading of the patch to other areas of the body. Subsequently, the patch will be immediately removed.

Treatment:

Drug: Capsaicin Patch 8% or 0.1% Capsaicin Cream