Hypothyroidism is a condition that occurs because the thyroid gland does not produce enough thyroid hormone. This can cause many of the body's system to slow down. The two main hormones that the thyroid gland produces are triiodothyronine (T3) and thyroxine (T4). These hormones influence your metabolism, brain development, rate of breathing, nervous system activity, muscle strength, skin dryness, weight, and cholesterol levels. There are many reasons why this disease develops. Recognizing the symptoms and getting an accurate diagnosis will help you and your doctor to find the right plan for treatment.
Initial Symptoms
The American Thyroid Association states that if the thyroid gland is not producing enough hormones, your body will make less heat and less energy, and organs like the brain and bowels move more slowly. You may begin to experience symptoms such as weight gain, feeling sluggish, dry and thinning hair, brittle nails, constipation and an intolerance to cold temperatures. You may become fatigued easily, your reflexes may slow and you can develop problems with your memory.
Additional Symptoms
With hypothyroidism, you may also notice decreased sweating, joint pain, muscle aches, impaired fertility, slower heart rate, heavy or irregular menstrual periods and feelings of depression. This condition can also allow a buildup of cholesterol in the body, increasing your risk of heart disease. In rare cases, your thyroid activity may slow to the point it becomes life threatening. The Hormone Foundation claims, "If you have severe hypothyroidism, a significant injury, infection, or exposure to cold or certain medications may trigger a life-threatening condition called myxedema coma. This condition may cause a patient to lose consciousness and to develop hypothermia, a life-threatening low body temperature."
Thyroid-Stimulating Hormone (TSH) Test
Since the symptoms of this disease can vary and be very general, you will need the right tests to confirm a diagnosis. Your physician will need to take into account a history of your symptoms along with a physical examination and certain tests in order to diagnose hypothyroidism. The most common test used is a blood test called the TSH test. According to the National Endocrine and Metabolic Diseases Information Service, "This test is the most accurate measure of thyroid activity available." When the thyroid gland is underactive, your pituitary gland releases TSH to stimulate the thyroid. When the level of thyroid hormones in the body reaches a normal level, then the pituitary gland reduces its production of TSH. In cases where they thyroid is chronically underactive, you will have high levels of TSH present. In most cases, a TSH blood test reading of above 4.0 mU/L on more then one test indicates hypothyroidism.
T4 Test
Most of the hormone T4 present in the body travels while attached to a protein called thyroxine-binding globulin, and it does not enter the cells. However, about 1 to 2 percent of T4 travels unattached (free T4), and this form can enter the cells. The T4 blood test shows the total T4 level and the levels of both free and attached T4 in the body. The University of Michigan Health Center states, "The normal range for total T4 is 5 to 13.5 micrograms per deciliter." A lower-than-normal level indicates hypothyroidism.
