High TSH levels in your blood indicate that your thyroid gland is underactive. This is known as hypothyroidism. If you have high TSH levels, you will probably need treatment in order to avoid any potential risks to your health.
TSH stands for thyroid stimulating hormone. It is produced in the rear of the pituitary gland. It stimulates your thyroid gland to produce thyroxine (T4) or triiodothyronine (T3), which are hormones that aid in the stimulation of metabolism.
If your pituitary gland produces TSH to stimulate your thyroid gland and that gland doesn’t respond properly, this excess TSH will be found in your bloodstream. It may be brought on by illness, stress, surgery or an obstruction that is causing your thyroid gland to be sluggish or malfunctioning.
What does a TSH Test Show?
TSH tests are lab tests that analyze the blood to determine your body’s levels of TSH. If you show signs that your thyroid is malfunctioning, your physician may run a test that checks for TSH levels in the blood. If you have a high TSH result, your thyroid may not be performing properly. Low TSH levels signify an overactive thyroid.
During your TSH test, blood will be drawn, to check the levels of hormones from the pituitary gland. Your arm will be sterilized, and then a needle will be used to take blood from your vein to a collection tube. If the blood does not flow easily, the technician may use an elastic band tightened around your arm. This makes it easier for the technician to collect your blood.
After the blood has been drawn, you will need to put pressure on the needle puncture, and then a bandage will stop any residual bleeding. The needle and elastic band do not cause significant pain, although a bruise may sometimes develop at the site of the injection.
When the results of this blood test are read, your physician will check for thyroxine (T4) and triiodothyronine (T3). These are the hormones responsible for controlling your metabolism. Results from the test are usually ready after two or three days from the drawing of blood. If you have high TSH levels, your physician will explain that your thyroid is malfunctioning, and let you know how this issue is treated.
What is the Normal TSH Range?
Your TSH level falls into a range of levels that measure the amount of TSH in your bloodstream. When you know what those levels mean, it will be helpful in your understanding of the problem and the treatment.
- Normal TSH
Adults that have a normal level of TSH in their blood will have results that fall between 0.4 and 4.2mU/L. This will indicate that the thyroid gland is responding properly to signals from the pituitary gland. Your level, along with other side effects and symptoms, will help your physician to figure out if you have a health issue.
- High TSH
Adults with high TSH levels usually have a thyroid that is underactive, also called hypothyroidism. It is often brought on by Hashimoto’s thyroiditis. If you are under treatment for a low thyroid issue already, this may mean that your medication needs to be increased. In rare instances, high TSH levels may be caused by tumors in the pituitary gland causing too much TSH to be produced, but this is very uncommon.
- Low TSH
Low levels of TSH may indicate that your thyroid is overactive. This can be caused by Grave’s disease, a goiter or non-cancerous tumors. The thyroid gland sometimes becomes overactive in the first trimester of a pregnancy, as well.
If you already are under treatment for thyroid problems, your TSH levels may be low if your dose of medication is too high. If there is no problem with the thyroid gland, then your pituitary gland may be producing too little TSH.
What Causes High TSH?
After your physician determines that you have high levels of TSH in your body, s/he will begin to focus in on what precisely is causing problems.
- Thyroid Disorders
Problems with the thyroid gland, like abnormal hormones, an enlarged gland or cancer may cause your thyroid to function sluggishly. Some conditions that cause this problem may be harmless, but others will need a medical intervention to stop unhealthy side effects. If your metabolism is sluggish, for example, this can cause damage throughout your body.
This condition means that your body isn’t producing sufficient hormones to properly manage your body’s metabolism. If you suffer from this problem, you may experience depression, irregular menstrual periods, high cholesterol, hoarseness, fatigue, constipation, an unexplained gain in weight, puffy face, aches in muscles, impaired memory, thinning hair, increased cold sensitivity or dry skin.
Hypothyroidism can be caused by several circumstances, including autoimmune disease, radiation therapy, surgery or psychiatric medication. This condition is generally managed using medication that replaces these hormones artificially.
- Pituitary Tumors
Rarely, high TSH levels may signal an improper functioning of the pituitary gland. Sometimes, that is caused by groups of cells atop the gland. These are not normally tumorous, but they can interfere with your body’s functions. They can lead to side effects that may cause your body danger. If your pituitary gland puts out too much TSH, it may lead to your thyroid gland becoming overactive.