Is hypothyroidism hereditary? If you suspect you may have hypothyroidism, your doctor will want to know your family medical history. Whilst this may infer that hypothyroidism is hereditary, it actually isn’t. The primary cause of this disorder in developed countries is Hashimoto’s disease, which is an autoimmune disease. What science has found is that the characteristics that predispose someone to developing an autoimmune disease in the presence of certain triggers are often genetic ie hereditary. Therefore, if you have a family history of autoimmune diseases you have a greater chance of developing an autoimmune disease like Hashimoto’s than someone who doesn’t have that family history. Autoimmune diseases also like company, so if you have one already you’re also at greater risk of developing another one. People with Hashimoto’s often develop, or already have, rheumatoid arthritis for example.
Some types of thyroid cancers are hereditary as they’re caused by inheritable mutations in certain genes. Medullary thyroid cancer is associated with mutations in the RET gene. Cowden Syndrome and follicular thyroid cancer is linked to mutations in the PTEN gene. People with SDH gene mutations and KLLN epimutations are at greater risk of developing papillary thyroid cancer. Surgery and / or radioactive treatment to remove these cancers often leaves the patient with either no thyroid or impaired thyroid function, leading to hypothyroidism.
Interesting Questions about Thyroid:
How is thyroid disease discovered?
As with any disease, it is important that you watch for the early warning signs. However, only your doctor can tell for sure whether or not you have thyroid disease. He or she can measure the amount of thyroid hormones in your blood, as well as look at the structure and function of your thyroid gland. If a nodule is found, your doctor can test whether or not it is cancerous.
What are the signs and symptoms of thyroid disease?
When your doctor examines you for thyroid disease, he or she should first ask about your symptoms and then check for physical signs. Your doctor will ask questions about your memory, emotions, or menstrual flow, and then check your heart rate, muscles, skin, and thyroid gland.
Which blood tests will my doctor use?
After a physical examination, your doctor may examine certain hormone levels in your blood. The most common tests check the levels of thyroid hormones (T4 and T3) and thyroid stimulating hormone (TSH). Your doctor may also perform a test with an injection of thyrotropin releasing hormone (TRH). If your doctor suspects Hashimoto’s thyroiditis or Graves’ disease, he or she will probably test you for antithyroid antibodies or thyroid stimulating antibodies.
What does the radioactive iodine uptake show?
Iodine is an important building-block for thyroid hormones. Your doctor may give you a small amount of radioactive iodine and then measure the amount absorbed by the thyroid gland. If the thyroid absorbs a lot of this iodine, you may be hyperthyroid. Low iodine uptake may signal hypothyroidism or thyroiditis.
Why is the structure of my thyroid important?
Which tests look at the structure of my thyroid?
- A thyroid image (or scan) shows the size, shape, and function of the gland. It uses a radioactive chemical, usually iodine or technetium, which the thyroid absorbs from the blood. A special camera then creates a picture, showing how much chemical was absorbed by each part of the gland. The test shows the size of the thyroid and tells whether lumps are hot (usually benign) or cold (either benign or malignant). The scan is frequently done at the same time as the radioactive iodine uptake.
- In needle aspiration biopsy, a small needle is inserted into the nodule in an effort to suck out (aspirate) cells. If the nodule is a fluid-filled cyst, the needle often removes some or all of the fluid. If the nodule is solid, several small samples are removed for examination under the microscope. Over 90% of the time, this testing tells the doctor whether the nodule is cancerous or not.
- Ultrasound uses high-pitch sound waves to find out whether a nodule is solid or filled with fluid. About 10% of nodules are fluid-filled cysts, and they are usually not cancerous. Ultrasound may also detect other nodules that are not easily felt by the doctor. The presence of multiple nodules reduces the likelihood of cancer.
When are thyroid hormone pills used?
Thyroid hormone pills provide the body with the right amount of thyroid hormone when the gland is not able to produce enough by itself. The pills are frequently needed after surgery or radioactive iodine therapy.
Thyroid hormone tablets are the standard treatment for hypothyroidism. While symptoms usually get better within a few months, most patients must take the pills for the rest of their lives. This is especially true for hypothyroidism caused by Hashimoto’s thyroiditis or radioactive iodine treatment.
If the entire thyroid gland has been surgically removed, thyroid hormone tablets replace the body’s own source of the hormone. If only a part of the gland has been removed, the pills may keep the remaining gland from working too hard. This decreases the chance that the thyroid gland will grow back.
How much hormone do I need?
The preferred hormone for treatment is levothyroxine (T4). You should use only the brand-name that your doctor prescribes, since generic brands may not be as reliable. Name-brand levothyroxine pills include Synthroid®, Levoxyl®, Levothroid®, Euthyrox®, and Eltroxin®.
Patients sometimes take more pills than they should, trying to speed up the treatment or lose weight. However, this can lead to hyperthyroidism and long term complications, such as osteoporosis. You should take the pills as your doctor prescribes.
At different times in your life, you may need to take different amounts of thyroid hormone. Therefore, you should see your doctor at least once a year to make sure everything is all right.
® Synthroid is a registered trademark of Knoll Pharmaceuticals.
® Levoxyl is a registered trademark of Jones Medical Industries.
® Levothroid is a registered trademark of Forest Pharmaceuticals.
® Euthyrox is a registered trademark of EM Pharma.
® Eltroxin is a registered trademark of Roberts Pharmaceuticals.
Are thyroid hormone pills needed after treatment for hyperthyroidism?
Many patients treated for hyperthyroidism become hypothyroid. They will need to take thyroid hormone pills for the rest of their lives. In addition, they will need to see their doctor at least once a year.
One of the more psychologically unpleasant and frustrating side effects that can occur with either hyperthyroidism or hypothyroidism is hair loss. There is no way to predict which patients will experience hair loss and which will not. Similarly, there is no way to predict who will be severely affected and who will have only minimal hair loss.
Because each person is unique, responses to thyroid disease and treatment will vary. This can be disturbing to patients who have lost a great deal of hair and want to know exactly when this will stop and when their hair will be normal again.
Here are a few facts to remember if you experience hair loss because of hyperthyroidism or hypothyroidism:
- Hair loss from thyroid disease is usually reversible with proper treatment of the thyroid condition.
- Typically hair loss does not immediately stop when the blood work becomes normal. Most people stop losing their hair and begin replacing lost hair a few months after the thyroid hormone levels become normal. In some cases, it can take longer.
- Stress can contribute to hair loss. Because of the nature of thyroid disease, it can have a direct impact on the psychological well-being of patients, particularly on the coping mechanisms that deal with stress. Unfortunately, as patients become more and more concerned about their hair loss, their stress levels increase, making the situation worse.
- It is advisable to take caution when considering chemical treatments of the hair-for example, coloring or permanent waves. If at all possible, avoid such treatments until the hair loss has stopped.
- Cutting the hair shorter, using moisturizing and conditioning hair products, and avoiding back combing are other methods to decrease stress on the hair.
The most important things you can do to minimize further hair loss are to faithfully take prescribed thyroid medications and to be calm and patient.
Have more questions? Need more answers? Check our Full Thyroid FAQ
Sarcoidosis on the thyroid glands can also impair thyroid function, causing hypothyroidism. There is plenty of evidence to suggest that genetic factors play a determining role in a person’s predisposition to develop this disorder too.
There are also various drugs that are used to treat hereditary disorders which can impair thyroid function if taken for long enough.
So Is Hypothyroidism Hereditary?
Clearly some of the conditions that can impair thyroid function, leading to reduced thyroid hormone production, which is hypothyroidism, have an element of genetic inheritance to them. However, hypothyroidism in and of itself is not hereditary.