Clinical trial NCT00829218: Clinical Trial Examining Effects of Monosodium Glutamate (MSG) on Irritable Bowel Syndrome (IBS) and Fibromyalgia (FM)
Official title: A Clinical Trial Examining the Effects of the Food Additive Glutamate on Irritable Bowel Syndrome and Fibromyalgia
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Irritable Bowel Syndrome
Fibromyalgia
Keywords: Irritable Bowel Syndrome
Fibromyalgia
Glutamate
Diet
Food additives
Lead sponsor: Oregon Health and Science University
Sponsor class: OTHER
Collaborators: name: University of Arizona
First posted: 2009-01-26
Enrollment: 60
Sex: ALL
Minimum age (years): 18
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: PREVENTION

Brief summary: Objective: Randomized, double blind, placebo-controlled, crossover, clinical trial to examine the effects of the food additive glutamate (in the form of MSG) on IBS and fibromyalgia.

Setting and Subjects: The Fibromyalgia Research Database at OHSU will be utilized to identify and recruit fibromyalgia patients who also have IBS to OHSU study centers.

Intervention: Approximately 60 male and female subjects aged 18-75 will be placed on a 1-month glutamate-free elimination diet. Those that respond positively to the diet (we are estimating 30-40 subjects), will then be randomized to receive either a citrus drink containing 5 grams of MSG; or placebo (the citrus drink alone)on three consecutive days one week apart.

The investigators are hypothesizing that those who react positively to the elimination diet will have symptom occurrence statistically more frequently when given the glutamate challenge, than when given placebo.


Eligibility criteria: Inclusion Criteria:

* Men and women aged 18-75 who fulfill criteria for Irritable Bowel Syndrome (IBS) and Fibromyalgia (FM)
* They must live in the greater Portland, OR, metro area, have transportation to/from study site, have access to email
* Willing to discontinue medications with bowel altering side effects

Exclusion Criteria:

* Asthma
* Inflammatory bowel disease
* Colon cancer or active endometriosis
* Any major abdominal surgery (excluding caesarean section, tubal ligation, hernia repair, gall bladder removal or appendectomy)
* Female and pregnant
* Currently taking pregabalin, gabapentin, or anti-psychotic medications and are unwilling/ unable to discontinue use
* Suffered from alcohol/substance abuse or psychosis in the last two years.

Primary outcomes:
measure: To evaluate the number of patients who have a positive response to a one month glutamate free diet, as measured by the Perception of Global Impression of Change (PGIC) scores
timeFrame: 4 weeks
measure: To assess whether symptoms return with MSG challenge statistically more frequently than with placebo as measured by symptom scores.
timeFrame: 6 weeks, 7 weeks
Secondary outcomes:
measure: Improvement on Irritable Bowel Syndrome-Quality of Life (IBS-QOL) questionnaire
timeFrame: 4 weeks, 7 weeks
measure: Improvement in day-to-day functioning based on the Revised Fibromyalgia Impact Questionnaire
timeFrame: 4 weeks, 7 weeks
measure: A reduction in pain based on two visual analog scales, one for gut pain, and another for musculo-skeletal pain
timeFrame: 4 weeks, 7 weeks
Other outcomes:
Locations:
city: Portland
country: United States
facility: Oregon Health & Science University
state: Oregon
Study officials:
affiliation: University of Arizona
name: Douglas Taren, PhD
role: STUDY_CHAIR
affiliation: University of Arizona and Oregon Health & Science Univ.
name: Kathleen F Holton, MPH, PhDc
role: PRINCIPAL_INVESTIGATOR
affiliation: Oregon Health and Science University
name: Kimberly D Jones, PhD
role: STUDY_DIRECTOR
References:
citation: Holton KF, Taren DL, Thomson CA, Bennett RM, Jones KD. The effect of dietary glutamate on fibromyalgia and irritable bowel symptoms. Clin Exp Rheumatol. 2012 Nov-Dec;30(6 Suppl 74):10-7. Epub 2012 Dec 14.