Effects of Low Dose Naltrexone in Fibromyalgia

Not Applicable

Completed

Conditions: Fibromyalgia
Persian Gulf Syndrome

Interventions: Drug: Low Dose Naltrexone
Drug: Placebo - sugar pill

Registration Number: NCT00568555

Lead Sponsor: Stanford University

Brief Summary: Low Dose Naltrexone (LDN) has been reported anecdotally to reduce the symptoms of Fibromyalgia, a Chronic Multisystem Illness. The drug may work by regulating natural pain-reducing systems. In this study, we will administer both LDN and placebo to a small group of individuals with Fibromyalgia and Gulf War Syndrome, both Chronic Multisymptom Illnesses, to assess the drug's efficacy in treating the condition.

Detailed Description: This study will be a placebo-controlled, double-blind, cross-over drug tria. Patients with Primary Fibromyalgia or Gulf War Syndrome will be recruited from the Stanford University Pain Management Center and the surrounding community. Participation in the study will cover 22 weeks. Participants will attend a laboratory session 12 times for progress checkups, and will complete daily measures of symptoms.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 53

Inclusion Criteria

Currently suffering from moderate to severe Fibromyalgia or symptoms of Gulf War Syndrome Age 18-65. Not taking any opioid analgesic Not pregnant or planning to become pregnant.

Exclusion Criteria

Any known allergy to naltrexone or naloxone. Actual or planned pregnancy.

Study & Design

Study Type: INTERVENTIONAL

Study Design: CROSSOVER

Arm && Interventions

Group	Intervention	Description
Low Dose Naltrexone first	Low Dose Naltrexone	LDN first, then placebo.
Placebo - sugar pill first	Low Dose Naltrexone	Placebo first, then LDN.
Placebo - sugar pill first	Placebo - sugar pill	Placebo first, then LDN.
Low Dose Naltrexone first	Placebo - sugar pill	LDN first, then placebo.

Primary Outcome Measures

Name	Time	Method
Percent Change in Pain Scores Between Baseline to End of Placebo Treatment and Between Baseline to End of LDN Treatment.	Baseline to end of placebo (2 weeks + 4 weeks) and baseline to end of LDN (2 weeks + 12 weeks)	Visual Analogue Scale for pain, 0 to 100, where 0=no pain and 100=worst pain imaginable. Baseline pain calculated averaging daily pain scores over the 2 week baseline period. Placebo and LDN pain scores calculated by averaging daily pain scores during the final 3 days of each condition. Values were converted to percent change in pain: \[(baseline pain - end point pain)/baseline pain\] x 100.

Secondary Outcome Measures

Name	Time	Method
Percent Change in Fatigue Scores Between Baseline to End of Placebo Treatment and Between Baseline to End of LDN Treatment.	Baseline to end of placebo (2 weeks + 4 weeks) and baseline to end of LDN (2 weeks + 12 weeks)	Visual Analogue Scale for fatigue, 0 to 100, where 0 = "no fatigue at all" and 100 = "severe fatigue". Baseline fatigue calculated averaging daily scores over the 2 week baseline period. Placebo and LDN fatigue scores calculated by averaging daily scores during the final 3 days of each condition. Values were converted to percent change in fatigue: \[(baseline fatigue - end point fatigue)/baseline fatigue\] x 100.
Percent Change in Heat Pain Sensitivity Between Baseline and End of Placebo Treatment and Between Baseline to End of LDN Treatment.	Baseline to end of placebo (2 weeks + 4 weeks) and baseline to end of LDN (2 weeks + 12 weeks)	A thermode is placed on the palm, and temperature is increased until the first sensation of pain. That temperature is recorded in Degrees Celsius . The procedure is repeated 3 times and results are averaged into a single temperature recording.
Percent Change in Sleep Quality Scores Between Baseline to End of Placebo Treatment and Between Baseline to End of LDN Treatment.	Baseline to end of placebo (2 weeks + 4 weeks) and baseline to end of LDN (2 weeks + 12 weeks)	Visual Analogue Scale for sleep quality, 0 to 100, where 0 = "did not sleep well at all" and 100 = "slept extremely well". Baseline sleep quality calculated by averaging daily scores over the 2 week baseline period. Placebo and LDN sleep quality scores calculated by averaging daily scores during the final 3 days of each condition. Values were converted to percent change in sleep quality: \[(baseline sleep - end point sleep)/baseline sleep\] x 100.
Percent Change in Pressure Pain Threshold Between Baseline and End of Placebo Treatment and Between Baseline to End of LDN Treatment.	Baseline to end of placebo (2 weeks + 4 weeks) and baseline to end of LDN (2 weeks + 12 weeks)	An algometer is used to apply pressure to 18 points across the body. Pressure is applied until the first sensation of pain in indicated. This pressure is recorded (as kg/cm2) and averaged for all 18 points to provide an overall score.