Avoiding the "Tyranny of the Test"
Finding Your Optimal Dose of Thyroid Medicine
By Richard Shames MD, with Karilee Halo Shames PhD, RN, HNC
First of all, 75 or 100 mcg. of thyroxine are a modest dosage for most adults. A well-known professor of endocrinology is convinced that a good "rule of thumb" eventual dose for most of his patients is one microgram per pound of body weight. For instance, a woman who weighs 137 pounds might do well with 137 mcg. of thyroxine (a few brands other than Synthroid are available in pills at this exact dose). A man who weighs 175 pounds might do well with the 175 mcg. pill. Before acquiescing to your doctor's test-result edict of final dose, you might want to ask for a short clinical trial of the medical center professor's protocol of "one mcg per pound of body weight". Keep in mind that the rule of thumb dosage is only a general initial guide, and that it might not apply well in cases of obesity.
If your doctor says "no, I realize you would like more medicine, but I don't think that is wise considering your test results," then you might want to look at your tests very carefully. Most likely your doctor is talking about the level of TSH (thyroid stimulating hormone). Many physicians are wrongly seeking to have their patients arrive at a TSH level that is in the mid-normal range. In actuality, the mid-normal range is a great target goal for most blood test results. However, it is not generally the most sensible goal of therapy for thyroid patients taking thyroid pills. Instead, for most thyroid sufferers, the goal of therapy should be to achieve a TSH near the low end of the normal range. Let us explain why.
The "normal" range of the TSH test generally runs from 0. 4 – 5.2. When I consult with people who call me from different parts of the country, I suggest to them a therapeutic target range of 0.3 – 0.5. This is at the low end of the test's normal range, not the mid-normal. The reason I do this is that most people who are suffering from low thyroid are ill because of antibodies from the immune system wrongly attacking the thyroid gland, and thereby compromising its function.
This immune attack is often lessened when the thyroid gland is stimulated as little as possible by TSH. Recall that TSH means "thyroid STIMULATING hormone". Rather, the person generally does better when her body runs on thyroid hormone pills, allowing the gland to be in a mostly unstimulated, resting state. The gland thereby receives a well-deserved vacation, in order to heal and repair the immune system damage that caused the illness in the first place.
Sometimes, both patients and doctors are concerned about this maneuver -- called "TSH suppression" -- where the TSH level is suppressed to just at or just below the lower end of the normal range. They evidently feel that giving the thyroid gland a healing vacation will cause harm or result in the gland being irreversibly turned off. After working in this way for a great many years, consulting for with numerous university specialists, and combing the relevant medical literature, I am totally convinced that thyroid glands are not at all injured by this maneuver.
If you haven't yet begun to feel as well as you would like, then you get to look at this TSH issue very carefully. If the dose of thyroxine you are currently taking (Synthroid, Levoxyl, Unithroid, Levothroid, L-thyroxine, Levothyroxine) has not resulted in a TSH that is down to the lower end of the normal range, then you may not be taking enough medicine. Neither I - nor any other doctor - can promise you that simply taking an amount of thyroxine to reach a TSH of 0.3, or 0.4, or 0.5 will give you full and lasting resolution of your thyroid difficulties. But I can tell you this – it is the next thing to try on your journey to full recovery. You may well be getting short-changed due to an under-informed or overly cautious medical provider.
Just last week I provided phone advice follow up appointments for four or five people from different parts of the county with this exact TSH issue. It is evidently quite common. I had advised them each, in earlier telephone consultations, to tell their practitioners that medical center endocrinologists commonly aim for a TSH of 0.2 before saying "That's enough thyroxine. More will not be a good idea". They know that insisting on a TSH well within the normal range often condemns patients to less than full recovery of function and enjoyment of life. All of the patients I spoke with in follow-up were pleased to report an improvement. The additional increase in their thyroxine dose resulted in a lower TSH level and also resulted in less symptoms.
One patient, who lives in St. Louis, had previously said his general practitioner was concerned about the possible adverse effect of thyroxine on the heart. When I asked the patient if the doctor had now found anything about heart function that was amiss, he said, "no, she did not." She had reported to the patient that the pulse, blood pressure, heart sounds, and cholesterol levels were actually all improved on the higher level of thyroxine that resulted in the lowered level of TSH. Nevertheless, she was still concerned about possible heart side effects. I was able to put both the patient and his doctor at ease with a quick call to the doctor. I reassured her that without any symptoms on the part of the patient or clinical signs able to be spotted by the doctor, the likelihood of adverse cardiac problems due to a lowered TSH was negligible. Only those people with a known history of heart arrhythmia, mainly atrial fibrillation, need to be so concerned.
Another phone consult patient was from Chicago. There, a doctor had told her that he did not want her TSH to go below 1.0 because he was concerned about osteoporosis from too much thyroxine.
First of all, as we detailed in our book Thyroid Power, this possible adverse effect of thyroxine is not really an issue unless the TSH is suppressed to a level that is below 0.1. (The laboratory results of a TSH that is clearly too low are often shown on lab reports as "less than 0.1", or 0.06, or "less than 0.01"). There is a world of difference between a TSH going below 1.0, which is quite okay to try, and going below 0.1, which should be discouraged.
Secondly, this factor is more of an issue in people who have osteoporosis in their family lineage, or who are already showing signs of osteoporosis themselves. Keep in mind, however, that many people who are being treated for low thyroid have early signs of osteoporosis BECAUSE OF UNTREATED OR LESS THAN FULLY-TREATED HYPOTHYROISISM. These two conditions are known to cause osteoporosis, worldwide they likely have in the past caused much more loss of bone density than has over-treatment with thyroid hormone. Appropriate doses of thyroid medication are not harmful to the bones of hypothyroid individuals.
The benefits of a full dose of thyroxine are enormous. A full dose could possibly lead to a full recovery. Many people are being prescribed less than a full dose, and are told to be satisfied with it. If you are going to take thyroxine, and just thyroxine alone, at least take an optimal amount of it. The actual proper amount of medicine varies tremendously from patient to patient. Also, keep in mind that taking thyroxine alone is not always your optimal choice.
You deserve to live the fullest life possible. Knowledge is power. We wish you full recovery and empowerment on your thyroid journey! Next article we will expand upon the topic of how to obtain additional benefit in symptom relief by simply switching brands (such as replacing Synthroid with Levoxyl). Stay tuned!
Richard Shames MD is a Harvard and University of Pennsylvania educated General Practitioner with over 30 years of experience. He is presently practicing in Boca Raton, Florida and Mill Valley/San Rafael, CA. He & Karilee Shames PhD, RN, co-authored the new HarperCollins book THYROID POWER: 10 STEPS TO TOTAL HEALTH. He is available for second opinion consultations all over the country via their website www.ThyroidPower.com. (Contact Anne at 561-353-2524 to schedule a consultation.)
All information is intended for your general knowledge only and is not a substitute for medical advice or treatment for specific medical conditions. You should seek prompt medical care for any specific health issues and consult your physician or health practitioner before starting a new treatment program. Please see our full disclaimer.