Hypothyroidism

The symptoms of hypothyroidism usually develop slowly over months or years.  Hypothyroidism causes your metabolic rate to slow down.  You may have a slow pulse and feel tired, sluggish, or weak.  You may want to sleep all of the time.  You may develop high cholesterol.  Your blood pressure may be too high or too low.  In rare severe cases, the heart muscle may weaken, leading to heart failure. 
 
You may feel unusually cold or have cold skin.  You may feel more comfortable in hot weather; however, you may not sweat.  This happens as your body works to conserve heat by redirecting blood away from your skin.  This will also cause you to look pale.  Your skin may develop a yellow color because of a buildup of carotene.  Carotene is normally converted to Vitamin A, but the conversion process is slowed by hypothyroidism. 
 
Your skin may also become dry and flaky.  Skin cracks may develop on your knees and elbows.  Your fingernails may become very brittle and develop lines and grooves.  You may also develop red itchy hives on your skin.
 
Your hair may become thin, coarse, and brittle.  It is common to lose hair, even to the point of balding.  You may also lose your body hair, including hair from your eyebrows, arms, legs, and pubic area. 
 
You may notice some changes in your digestive system because your body has slowed down.  Food may not move through your stomach and intestines as fast as it did before.  This can cause constipation, hard stools, bloating, and heartburn.  Additionally, some people gain weight when their metabolism slows down.
 
Females may experience irregular menstrual periods that are heavier and last longer.  In some women, the ovaries stop producing eggs, which can cause infertility.  You may also overproduce prolactin.  Prolactin is the hormone responsible for milk production.  Your breasts may produce discharge, even if you are not currently breastfeeding.  Too much prolactin can also interfere with menstruation and ovulation. 
 
You may experience muscle aches and cramps.  The pain may be severe enough to wake you up at night.  You may lose your coordination and feel clumsy.  You may feel a “pins and needles” sensation and develop carpal tunnel syndrome. 
 
Hypothyroidism can cause memory problems, poor concentration, and depression.  Depression is a real medical condition that can be treated.  Symptoms of depression include continually feeling sad, irritable, tired, and uninterested in activities that used to be enjoyable.  Other common symptoms of depression include changes in appetite, sleep difficulties, moving the body at a much slower pace, and not being able to remember things or concentrate as easily as before.  Memory problems, poor concentration, and depressive symptoms in older adults can be similar to those of dementia or Alzheimer’s Disease.  It is important for people with cognitive changes to get a thyroid function test. 
 
Your thyroid may enlarge if it is inflamed and especially if you have Hashimoto’s Thyroiditis.  Your vocal cords may be affected by the enlarged thyroid gland.  This can cause your voice to sound hoarse. 
 
Hypothyroidism rarely occurs in infants and children.  If it is treated in the first month of life, the child can grow and develop normally.  If untreated, hypothyroidism can cause brain damage, mental retardation, developmental delays, and slowed physical growth and sexual development.

It is important that you tell your doctor about your symptoms.  Your doctor can begin to diagnose hypothyroidism or subclinical hypothyroidism by reviewing your medical history, conducting a physical examination, and with blood tests.  Subclinical hypothyroidism is hypothyroidism that has not progressed very far and has not yet caused symptoms.  If subclinical hypothyroidism is detected, it can be treated before symptoms develop. 
 
Your doctor can determine if you have hypothyroidism by testing your blood.  The most common blood tests are the Thyroid-stimulating hormone (TSH) assay and the Thyroxine (T4) measurement.  The Thyroid-stimulating hormone (TSH) assay is used to determine if the thyroid gland is functioning properly.  It can identify if an underactive gland is caused by a problem with the pituitary gland, hypothalamus, or a damaged thyroid gland.  The Thyroxine (T4) measurement assesses thyroid functioning by testing how much T4 is in the blood.  If the Thyroid-stimulating hormone (TSH) assay and the Thyroxine (T4) measurement are not normal, an Antithyroid Antibody Test is used to determine the presence of Hashimoto’s Disease.
 
On occasion, a doctor may order a Thyroid Ultrasound or a Thyroid Scan and Radioactive Iodine Uptake (RAIU) Test.  Thyroid scans can detect problems with the thyroid gland.  They can identify how the thyroid gland is functioning and specify areas of overactivity or underactivity.  Further, they can determine if thyroid nodules or cancer are present. 
 
Additional blood tests and medical imaging tests are done to diagnose rare forms of hypothyroidism caused by diseases affecting the hypothalamus or pituitary gland in the brain.  A blood test called the Thyrotropin-Releasing Hormone (TRH) Stimulation Test measures the amount of TRH produced by the hypothalamus.  TRH is the hormone that signals the pituitary gland to produce TSH.  A Computed Tomography (CT) Scan or Magnetic Resonance Imaging (MRI) Scan is used to view the brain structures.  CT scans provide a view in layers, like the slices that make up a loaf of bread.  The MRI scan is very sensitive.  It provides detailed images.  The CT and MRI scans are painless procedures.