Guaifenesin remains a controversial treatment for FM with many pros and cons.
Read Kathy Longley on the case for and against in the August,September and October 2001 issues of FaMily magazine. Click here.

Excerpted from "What Your Doctor May Not Tell You About Fibromyalgia", by R. Paul St. Amand MD, and Claudia Marek. All rights reserved.

I will consider changing my medications, my physical therapies, and my exercise routines, but I will not consider going without Guaifenesin, nor will I take anything that might block its effect. It's too important to my well-being. It is not a cure. I must still practice sound nutrition, bodywork, mind work and the other lifestyle modifications important to the FMS&MPS complex patient, but I feel that Guai has made a decided difference in my quality of life, and allowed me to do much more than I could have done otherwise. I want others to know that there are options.

Guaifenesin therapy was developed by Dr. R. Paul St. Amand. It is experimental. We don't know how it works. The one study done on Guaifenesin and FMS was flawed, through no fault of those who ran it (St. Amand R. P. and C. Potter. 1997. "The use of uricosuric agents in fibromyalgia theory, practice and a rebuttal to the Oregon study of Guaifenesin treatment." Clin Bul Myofas Ther 2(4):5-17.). We simply didn't know all the variables at the time the study took place, including the importance of diet for reactive hypoglycemia for the reversal to become evident, and the need for each person to find their specific dosage for the reversal to take place.

What is Guaifenesin and Where Do I Find It?

Guaifenesin is a common over-the-counter expectorant. It has been around for about seventy years, first as guaiacum and then as guaiacolate, and for about twenty years as Guaifenesin. Guaifenesin is not a cure for FMS. It does seems to allow the kidneys to eliminate something harmful that has been stored in the body.

Dr. St. Amand feels that at least part of what is eliminated is phosphates, and I agree. Oxalates may also be part of this package of unwanted stored matter that is released by Guaifenesin. Excess oxalates seem to be responsible for some of the vulvitis and vulvodynia experienced by female FMS patients.

St. Amand found that with Guaifenesin therapy, there was an increased excretion of 60 percent phosphates, 30 percent oxalates and 30 percent calcium. Although you lose excess calcium, none of his patients has exhibited any sign of osteoporosis or calcium loss. Emphysema patients on Guaifenesin often take 2400 mg a day for many years without any side effects.

Guaifenesin is safe and even available in pediatric dosages. It is also sold in as a prescription medication available in 600 mg caplets or capsules. It is important to ensure that there are no other medications mixed in with the Guaifenesin, as there often are in cough and cold formulations.

How Do I Know It's Working?

St. Amand feels that FMS develops in a cyclical process. At first, there are times when we experience symptoms interspersed with periods where we feel ok. Sometimes we are unaware of what is happening at this stage. The periods without symptoms get shorter, the symptomatic episodes become more frequent and the symptoms worsen. This is what St. Amand calls "cycling".He believes that Guai therapy reverses this process.

Your urine and sweat may become dark and smelly as Guai takes effect. I believe that this indicates a release of wastes, excess acids and, I believe, toxins, as well as substances such as quinolinic acid, the nerve toxin produced by the kynurenine pathway of tryptophan metabolism (see Alternative Tryptophan Pathway, Chapter 5, The Fibromyalgia Advocate). This release into the bloodstream is manifested by muscle aches, headaches, and often overwhelming fatigue. This includes physical problems as well as psychological ones, including feeling depressed at times during the cycle. With the release of the wastes into the blood stream, your body can begin to process these unwanted substances, and get rid of them through the urine, faeces, and sweat. Your faeces may become irritating, and you may experience anal itch or soreness. This can be eased by Bag Balm, anesthetic ointment, or cortisone ointment. You may also experience burning on urination, caused by the excess acid (see Fibromyalgia and Myofascial Pain Syndrome: The Survival Manual).

After the initial flush of wastes, you will begin to go through a reverse of the cyclical process. Every once in a while you will have a period where your symptoms ease. You may then begin to experience whole days where you feel well. It is important not to overdo on these days. Your body is in a struggle to regain balance. Don't overtax it.

When you get to the point where there are clusters of good days, the contrast can be remarkable.

Knowing what is happening helps you to deal with the reversal symptoms. The bad days are still bad, but you know why, and you know you are on a path to better health.

Guaifenesin Therapy

Before you begin Guaifenesin therapy, use the body chart found in The Fibromyalgia Advocate map your areas of pain. This will allow you to record any progress. (Alternatively use the symptom diary from - Ed)

The typical regimen is to start with 300 mg twice a day. I have seen some people start gentle Guai therapy on 200 mg a day. It is important to find the dosage that works for you. This varies from patient to patient. If, after one week, no obvious change occurs, increase the dose to 600 mg twice a day for a few weeks. Pay attention to your body. If, after this time, no sign of reversal is evident, try 600 mg three times a day. This is the dosage I am on, and have found effective for me. Each of us is different. The break up of pain areas in spite of an increase in symptoms means the stored waste matter is leaving your body.

Guaifenesin And Diet

There is no "Guaifenesin" or "fibromyalgia" diet. It is important those of you with co-existing reactive hypoglycemia to follow a low carbohydrate diet if you want to feel better during Guaifenesin therapy.

I have found the Zone diet helpful (see "Reactive Hypoglycemia", and "Books and Tapes"). A strict low carbohydrate diet is a must for those who are overweight as well as hypoglycemic.

Salicylate Blocking Effect

The effect of Guaifenesin therapy can be blocked by salicylates. Dr. St. Amand explains what
happens in this way: "All cells have little garages called "receptors." They are each unique for certain chemicals and hormones. To work, any medication must have the ability to enter and park in the garage in order to signal the cell to do a certain job.

Guaifenesin parks in receptors to get the kidney cells to do the work you need done. Unfortunately, salicylates are a much better fit for that garage and the valet will park salicylates in preference to anything else. When Guaifenesin arrives in the parking lot, there are no available garage spaces. Thus no signal is given for our desired effect."

The effects of a Guaifenesin blocking agent may last about 24 hours. Salicylates are found in some medications and topical creams, for example some muscle rub products and sunscreens. It is also present and often hidden in a great array of cosmetics, some ultrasound gels, mouthwashes and herbal preparations. Everyone on Guaifenesin should avoid obvious sources of salicylates such as aspirin and other blatant salicylates (Diflunsal, Methyl salicylate, Trisalicylate), plant extracts (aloe, licorice, pycnogenol, St. John's Wort, ginko, quercetin etc).

Each person seems to have a different sensitivity to the Guai blocking effect of certain salicylates, If you've found your proper dosage and suddenly the cycling stops and your symptoms worsen, check out secondary sources such as camphor, almond oil, coconut oil, lauric acid, etc. I've seen this happen to me and to others, and we've always been able to track down the offending salicylate and eliminate it, with a subsequent return to improvement. These setbacks and subsequent resolutions are yet another indication to me that we are on the right track with Guai.

Only phosphate is known to decrease ATP formation when it accumulates in the mitochondrial matrix. The mitochondria are the body's energy factories, and ours are polluting badly. Low ATP has been found in people with FMS (Park J. H., P. Phothimat, C. T. Oates, M. Hernanz-Schulman and N. J. Olsen. 1998. "Use of P-31 magnetic resonance spectroscopy to detect metabolic abnormalities in muscles of patients with fibromyalgia." Arth Rheum 41(3):406-413; Eisinger, Plantamura and Ayavou 1994). ATP is essential to almost all cellular functions.

Both Dr. St. Amand and I suspect a lowered pH is at least part of the FMS problem. The pH is a measure of the acid/base balance of the body. Low pH indicates acid. Dr. St. Amand used his observational skills and deductive logic to theorize what is happening in our cells. Sherlock Holmes would have been proud.

At 300 mg Guaifenesin twice a day, Dr. St. Amand found that about 20% of his patients reverse--and this reversal is often swift and strong. About 70% patients reverse at 600 mg twice a day. The rest of us need a stronger dosage. Once your symptoms are made distinctly worse by a given dose, that is probably the proper dose for you. Just remember, your body has a limited capacity for clearing out the debris. Give it the time it needs, and be gentle with yourself when you begin Guaifenesin therapy.

If your symptoms have been relieved, it may be time to see if you can do without your other
medications, one at a time. Talk to your doctor about this. Once this has been done, and if your symptoms don't return, you may want to try to drop the Guaifenesin dosage. Do this gradually.

According to Dr. St. Amand, some people cut back a half pill at a time and wait about three months or so before they cut back another half pill. People are reluctant to jeopardize their hard-won health.

You have cut down too far when the symptoms return, so just resume what dosage you were on when you had no symptoms. This is your maintenance dose.

Your doctor may contact Dr. St. Amand at the following:
R. Paul St. Amand, M.D.
4560 Admiralty Way, Suite 355
Marina del Rey, CA 90292

Visit Dr. St. Amand's website.

For the full details on Guaifenesin therapy, plus a lot of information on fibromyalgia, read the book "What Your Doctor May Not Tell You About Fibromyalgia" by R. Paul St. Amand and Claudia Craig Marek.

Other websites that may be useful:


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