This is a letter from the leading endocrinologist at the Tampere University Hospital to all public medical practitioners in the Pirkanmaa health care district. I’ve heard that this has happened in other districts as well. Please share. And please comment!
How to deal with therapeutic problems in hypothyroidism, and patients who have used T3 medication
The number of remissions to the Tampere University Hospital concerning therapeutic problems in hypothyreosis and especially the use of T3 have soared. We ask the remitting physician to note the following, when assessing the need for a remission to special medical care.
1. Is the patient hypothyroid? When, by whom, and on what grounds has the diagnosis been given, or the care initiated?
Hypothyreosis is diagnosed or ruled out by measuring S-TSH and S-T4V (free T4). If the results indicate a mild, subclinical hypothyreosis, it’s advisable to repeat the S-TSH after 1-3 months, and at the same time measure the S-TPO antibodies. If they are positive, the subclinical hypothyreosis may be treated. Thyroxin® can be tested in subclinical hypothyreosis if TSH is repeatedly higher than 4 mU/L. In people over 70 years of age, subclinical hypothyroidism should not generally be treated. Hypothyreosis should be treated, if S-TSH is ≥ 10 mU/L. For pregnant women and women who plan to get pregnant, thyroxine treatment should be started, if TSH ≥ 2,5 mU/L.
Functional medicine practitioners offer reverse T3, rT3 tests from abroad for a high price. This is not needed in clinical practice, because rT3 is an inactive thyroid metabolite.
2. The patient doesn’t feel better on Thyroxin® test therapy
According to the recommendations for care of subclinical hypothyroidism (TSH > 4 mU/L and free T4 is normal), a test treatment on thyroxine is done for 3 months, and after that a check, whether the symptoms have disappeared, is done. It’s fairly common, albeit not according to recommendations, that a test therapy is done at low values in euthyreosis (TSH and free T4 within range but low). If the symptoms continue during the test, or symptoms of thyrotoxicosis show up (palpitations, sweating, irritability, muscle weakness), the test should be terminated. Other reasons and solutions should be looked for to the original symptom, which is most often fatigue, weight gain or ”brain fog”. The most common causes are problems related to control of life, like stress, too much work, sleeplessness, lack of exercise, problems with eating schedules, overweight). Factors like sleep apnea, depression, hypercalcemia, diabetes, anaemia, vitamin B12 deficiency and electrolytic imbalances should also be checked.
3. The patient has had treatment for ”Wilson’s syndrome”
Functional medicine practitioners issue T3-medications for reasons that aren’t based on medical scientific evidence. The sole use of synthetic triiodothyronine (T3, trade names Liothyronin® and Thybon®) leads to thyrotoxicosis. Because the half life of T3 is short (around 24 hours), the problem with T3 treatment is the huge diurnal variation in T3 concentration. Typically the patient is in thyrotoxicosis for 3-4 hours after taking the T3 preparation. Thyrotoxicosis makes the patient tired, and causes arrythmia, irritability and sweating. In the morning, before the morning medications, the TSH, free T4 and free T3 values are typically low. Especially for pregnant women, or women who plan to get pregnant, T3 therapy is connected to the risk for the fetus to be hypothyroid and mentally retarded, because T3 does not surely penetrate the placenta, and the fetus is depending on the mother’s thyroxine during the development of the brains. Any T3 administration without medical grounds shall be terminated. There’s no need to gradually lower the dose. Pregnant women can be administered 25 – 50 µg of Thyroxin® to protect them from short term hypothyreosis. Because the T3 preparations work for a short time only, the patient’s own HPT axis will recover quickly. The thyroid function tests should be done after a month, and are usually normal. Then the original symptoms should be assessed, the reason that the patient visited a functional medicine practitioner in the first place.
4. The patient is hypothyroid because of autoimmune thyroiditis, thyroid surgery, or RI treatment, but is dissatisfied with the thyroxine replacement therapy
The recommended care for hypothyroidism is Thyroxin® monotherapy. Levothyroxine has a long half life (around one week), and stable T3 levels are obtained in the tissues through deiodination. Thyroxin® is taken once daily. Iron and calcium tablets should not be taken simultaneously with Thyroxin®, because these preparations lessen the uptake of Thyroxin®. Acid blockers and estrogen preparations raise the need for thyroxine. Most patients feel well on T4, as long as the dose is correct. The dose is correct, when the patient feels well, TSH is around 1 mU/L, and free T4 is in the reference range. Some patients feel best mentally, when free T4 is in the upper range and TSH is low. Free T3 must not rise above the reference range in this case. The most suitable levels can be individually assessed by measuring the thyroid function tests 6 weeks after raising the dose. Senior patients’ TSH should be in the upper part of the range. Subclinical hyperthyreosis makes the patients prone to osteomalasia and heart and blood vessel morbidity.
5. NDT (trade names Armour Thyroid and Thyroid) should not be used for the treatment of hypothyreosis
Synthetic combination therapy T4 + T3 may be tested on patients, who have a proven diagnosis of hypothyroidism, and who have not benefitted from correct doses of T4. Other possible reasons for fatigue must first be ruled out. In such situations a three month test therapy on T4 + T3 should be done by an internist or an endocrinologist, who is knowledgeable in thyroid illnesses. Combination therapy is not recommended for pregnant women and people with arrythmias. The risk in combination therapy is thyrotoxicosis caused by a too large dose. This can be seen as low TSH.
2012 European Thyroid Association Guidelines: The Use of L-T4 + L-T3 in the Treatment of Hypothyroidism. Wiersinga WM, Duntas L, Fadeyev V, Nygaard B, Vanderpump MPJ. European Thyroid Journal 2012: 1:55–71.
2012 Clinical Practice Guidelines for Hypothyroidism in Adults: Co-sponsored by American Association of Clinical Endocrinologists and the American Thyroid Association. Garber JR, Cobin RH, Gharib H, Hennessey JV, Klein I, Mechanick JI, Pessah-Pollack R, Singer PA, Woeber KA. Endocrine Practice 2012. Thyroid 2012: 22.
2013 ETA Guideline: Management of Subclinical Hypothyroidism. Pearce S, Brabant G, Duntas L, Monzani F, Peeters R, Razvi S, Wemeau JS. Eur Thyroid J 2013;2:215–228
Kilpirauhasen vajaatoiminnan yhdistelmähoito (Combination therapy of hypothyroidism, in Finnish). Niskanen L. Suomen Lääkärilehti 2013; 13/14.