Q1: I have an underactive thyroid and have just had a thyroid function test. My doctor tells me that my levels are normal, but I still feel lousy. ANSWER

Q2: Will I get osteoporosis if my TSH level is too low? ANSWER

Q3: When should I take my thyroxine tablets? ANSWER

Q4: What should my TSH and T4 levels be? ANSWER

Q5: I have just started thyroxine replacement therapy and I have palpitations and am feeling tense and 'hyped' up. ANSWER

Frequently Asked Questions at Other Sites:

Q1: I have an underactive thyroid and have just had a thyroid function test. My doctor tells me that my levels are normal, but I still feel lousy.

What your doctor is really saying is that your various thyroid hormone levels are within their so called Reference Ranges. Simply having your hormone levels within the reference range does not of itself mean that you will feel well. It is also important to know which hormones have been tested and where in the Reference Range your readings have fallen. The Reference Range for each hormone also depends on the pathology laboratory which conducts the test. This is because each laboratory's equipment is calibrated differently. You must therefore get a photocopy of your results because the report will show the Reference Range for you.

If you have previously been diagnosed with a thyroid condition, your test should include readings for TSH (Thyroid Stimulating Hormone) and FT4 (Free Thyroxine). We recommend that all diagnosed thyroid patients should also have their FT3 (Free T3 or Free Triiodothyronine) level tested. We find that thyroid patients frequently only have their TSH level tested. This is inadequate for the proper clinical management of thyroid conditions. If this is all you have had tested, you should return to your doctor and insist on a Full Thyroid Function Test including Free T3.

After speaking to many hundreds of thyroid patients, it is our experience that all of those whose FT4 and FT3 levels fell in the lower half of their Reference Ranges felt 'lousy'. It is therefore likely that your FT4 and FT3 levels are in the lower half of the Reference Ranges. If they are, you should approach your doctor to raise your dose. You could use the following argument:

"I know that my hormone levels are within the Reference Range, but they are at the lower end and I am not felling well. I have some room to move within the Reference Range and would like to try a slightly higher dose under your control. I would like to increase my dose by 25mcg (or 50mcg) for a few weeks and have another blood test at the end of the period to see how I am going. Can you please help me feel better?"

If your doctor is hesitant (and in our experience many of them will be) refer them to the following statements by eminent endocrinologists:

Prof Jim Stockigt of Melbourne, in a recent interview with Sigma Pharmaceuticals said, "there are now a couple of rather conclusive double-blind crossover studies against placebo showing symptomatic improvement when people with mild thyroid failure - particularly older women - are treated with thyroxine". When discussing treatment, he also said "The important point here is that when normalising TSH therapeutically, our target (our mean and median) TSH value is around 1mU/L. If we fail to realise this point, a number of individuals will remain under-treated."

Sir Richard Bayliss, wrote in 1995 for the British Thyroid Foundation, "Certainly it is my experience that patients feel at their best when the free thyroxine level is towards the upper end of the reference range or marginally above it and the TSH towards the lower limit of the normal range."

Dr A D Toft, also for the British Thyroid Foundation, wrote, "The correct dose is that which restores good health; in most patients this will be associated with a level of T4 in the blood towards the upper part of the normal range or even slightly high and a TSH level in the blood which is in the lower part of the normal range", adding that, "In a small number of patients well-being will only be achieved if TSH is low but in this circumstance the concentration of T3 in the blood will be unequivocally normal."

Dr M G Prentice, writing an article entitled Thyroid eye disease and its symptoms - an endocrinologist’s view, for the TED Association said: "Very similar symptoms to non-specific but quite severe symptoms sometimes suffered during an acute thyroiditis or acute thyroid eye disease are those suffered by patients who have been thyrotoxic for some time and are then, through treatment, rendered euthyroid with normal thyroid function. It is well recognised by some groups in Scandinavia that these patients may suffer a form of thyroid withdrawal. This can be very uncomfortable for the patient, feeling as though the plug has been pulled, as some of them describe it. They lose all of their energy, everything becomes an enormous effort and they suffer from aches and pains, hot and cold feelings and feel generally unwell and often depressed also. In this group of patients, if I suspect some of their symptoms may be due to this effect, I may raise their thyroxine replacement temporarily to give them free thyroid hormone levels near the upper range of normal and gradually wean them down over a period of a year or two."

Professor Stockigt's interview can be read in full here. Complete copies of the articles written by the other doctors can be obtained by contacting us.

If your doctor does not wish to assist you manage your thyroid condition, you should ask for a referral to an endocrinologist and/or seek another doctor who will work with you.
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Q2: Will I get osteoporosis if my TSH level is too low?

TSH (Thyroid Stimulating Hormone) is a regulatory hormone. It controls the activity of the thyroid gland and does not have a direct impact on the bones. TSH moves in response to the level of thyroxine (T4) in the blood, falling when T4 rises and vice versa. A low level of TSH indicates a high level of T4. The real question is whether a high level of T4 will cause osteoporosis.

There is no doubt that people who have endured elevated levels of T4 and the other thyroid hormone T3 (Triiodothyronine) for extended periods due to hyperthyroidism have suffered reductions in bone density. It is clear therefore that people who have T4 and T3 levels above their reference ranges have a greater risk from osteoporosis. These people will undoubtedly have had TSH levels below the reference range so there would be a correlation between the low TSH and osteoporosis.

People taking replacement thyroxine for hypothyroidism commonly have TSH levels near the lower limit of its reference range and sometimes even below the lower limit without their T4 or T3 levels exceeding their reference ranges. In these circumstances, there is little reported evidence of any risk of osteoporosis. The situation is summed up by Professor AP Weetman in the British Medical Journal 314 (1997) when answering the question as to whether there are any risks to taking thyroxine "Providing thyroid stimulating hormone concentrations are restored to the reference range, the answer is no, and even if too much (thyroxine) is given, the risks of osteoporosis are more theoretical than real." Results presented in June 2000 to the World Congress on Osteoporosis by Dr M Stenstrom of the University of Gothenburg Sweden indicated that there was no significant difference in Bone Mineral Density in 768 women taking thyroxine when compared to a control group.

This issue is related to the topic discussed in Question 1 because osteoporosis is frequently used as the reason for not increasing the thyroxine dose to a level which relieves symptoms. You have a high probability of suffering continuing hypothyroid symptoms (possibly severe) if T4 and T3 levels are at the lower end of the reference range. Your probability of suffering osteoporosis if T4 and T3 levels are at the upper end of the reference range is unproven and if there is a risk, it would appear to be small.
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Q3: When should I take my thyroxine tablets?

Sigma Pharmaceuticals, the makers of Oroxine and Eutroxsig, recommend that the tablets be taken by themselves first thing in the morning on an empty stomach. This ensures that there are no interactions with drugs you might be taking. It also ensures that the absorption of the thyroxine is not influenced by whatever you might have eaten. You get a consistent experience each day.
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Q4: What should my TSH and T4 levels be?

The reference ranges for the various thyroid related hormones are unfortunately not fixed. They vary from laboratory to laboratory and depend on the specific test used and the calibration of the analytic equipment. You should therefore always get a photocopy of your test results as these will show the reference ranges for each hormone tested.

The table at the right shows some indicative reference ranges for the three most important hormones. You should ensure that you have all three hormones tested. Testing TSH alone is not sufficient for the clinical management of thyroid conditions, but this is all that pathology laboratories will test for unless specifically requested to do the other tests.

Keep copies of your test results and record on the report how you felt when you went for the test. This will allow you to refer back to your results to see what the appropriate T4 and T3 levels are for you to feel well. We also have a form on our download page which allows you to keep a record.

You should also read Question 1.
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Q5: I have just started thyroxine therapy and am feeling hyped up?

A small percentage of people starting out on thyroxine experience this problem. They experience the hyperthyroid type symptoms of palpitations, agitation, tension and general feelings of being 'hyped' up. The problem seems to be that their bodies have adapted to being hypothyroid and their tissues and organs react strongly to the newly increased thyroid hormone levels in their blood. For some people, the effect lasts for a couple of days and then goes away, but for others, it persists.

If the problem persists, the only answer to the problem is to take things more slowly. You will need to take a smaller dose to get you started and you will probably need to increase your dose more slowly as you move to your final stabilised dose. You sholdn't do this by yourself. If the problem persists, you should tell your doctor and discuss the slower approach.

You can also obtain information on thyroxine HERE.
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