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There have been reports that some ingredients in cough and cold medicines have been successfully used as a treatment option for fibromyalgia. Is there any evidence that guaifenesin is effective for treating fibromyalgia? Have you ever prescribed it to patients?

A.

What is Guaifenesin?

Guaifenesin is an expectorant and mucus thinner used to help the symptoms of cough. It also has the ability to increase the elimination of phosphates and uric acid by the kidneys.

Paul St. Amand, M.D., an adviser in the study, hypothesized that patients with fibromyalgia have a defect in their body's ability to eliminate phosphates. As a result, the phosphates would combine with calcium in the muscles and cause pain. Taking guaifenesin, he hoped, would eliminate this excess product and relieve patients pain.

• St. Amand's Fibromyalgia Treatment Center

The Theory: Guaifenesin Relieves Fibromyalgia Pain

Initially, patients would feel worse instead of better because of the increase of the calcium/phosphate product in the bloodstream. Yet, when his theory was tested in a placebo-controlled study by Robert M. Bennet, M.D., and Sharon Clark, Ph.D., there was no benefit with the use of guaifenesin compared to placebo. Dr. St. Amand felt that the negative result could be due to the fact that many medications and other products contain salicylates which prevent the elimination of the phosphate.

He still recommends this treatment for fibromyalgia patients. The risks of this therapy are felt to be limited and one can learn which products contain salicylates from an article published by Ruth Winter and is reproduced in Dr. St. Amand's book, What Your Doctor May Not Tell You About Fibromyalgia.

Dr. Scott Zashin's Conclusion

Remember, there are no scientific studies showing benefit with this treatment, and patients may feel worse with this treatment. Still, I do have a few patients who try this therapy, some with success.

_{Answers provided by Scott J. Zashin, M.D., clinical assistant professor at University of Texas Southwestern Medical School, Division of Rheumatology, in Dallas, Texas. Dr. Zashin is also an attending physician at Presbyterian Hospitals of Dallas and Plano. He is a fellow of the American College of Physicians and the American College of Rheumatology and a member of the American Medical Association. Dr. Zashin is author of Arthritis Without Pain - The Miracle Of TNF Blockers. The book is useful for anyone on one of the biologic drugs (Enbrel, Remicade, Humira) or considering the biologic drugs. Read my review of the book.}