QUESTION: I have had to take some type of thyroid medication for the better part of my adult life.
I started with simple thyroid tablets years ago, but as I have had to change doctors over the years, both the type and amount of my medications have also been changed.
When I ask about it, the doctor usually just shrugs his shoulder and tells me "it's too complicated to explain".
I suppose it is too complicated for you too, but I hope you will try for my benefit and lots of your other readers.
ANSWER: It is not all that complicated, but its a bit more difficult without being able to draw a diagram or two.
However, here we go.
The thyroid gland produces two chemicals, thyroxine (T4) and triiodothyronine (T3).
T3 is the biologically active form of thyroid hormone, and T4 acts as a reserve which can be rapidly converted into the active form when needed.
The hypothalamus, located at the base of the brain, monitors the amount of T3 and T4 circulating in the blood and releases a hormone, thyrotropin releasing hormone (TRH), when more thyroid hormone is needed.
TRH acts on the pituitary gland, which in turn produces thyroid stimulating hormone (TSH) which "stimulates" the thyroid gland into thyroid hormone production.
To provide additional hormone to patients who do not produce enough of their own, a variety of preparations made from dried and purified extract of animal thyroids can be used.
Though every effort is made to maintain the exact dosage, the concentration of T3 and T4 in these natural preparations may vary.
However we now have a number of synthetic preparations available in which the active ingredients are well controlled.
It is probably these newer preparations which have been substituted for the extract you were taking formerly.
Since we can also determine the amount of TSH, T3 and T4 circulating in the blood, these tests are used to assure that the right dosage is being taken to restore the body metabolism to normal.
When this achieved the signs of hypothyroidism lethargy and dullness, sparse and dry hair, coarse and scaly thick skin rapidly disappear.
Now, I hope my explanation was not too complicated, but provides the information and help you requested.
The material contained here is "FOR INFORMATION ONLY" and should not replace the counsel and advice of your personal physician.
Promptly consulting your doctor is the best path to a quick and successful resolution of any medical problem.
