Hashimoto’s disease

If the thyroid doesn’t make enough hormones, it has a negative effect on a number of body functions. This is reflected in the wide range of symptoms.

Many people feel generally weak, and often tired and cold too. There can be visible changes in the body. For example, the person’s neck can swell because the inflammation sometimes results in an enlarged thyroid (known as a “goiter”). Later, the thyroid can also shrink a lot. Their skin may become dry or swollen too, making their face look somewhat puffy. Some people put on weight.

Hoarseness, constipation, a slow heart rate, menstrual (period) problems and erection problems can also occur. Other possible symptoms of an underactive thyroid include mental health problems such as a low mood or lethargy.

The thyroid inflammation that occurs in Hashimoto’s disease is caused by an autoimmune reaction: The person's immune system attacks their own thyroid tissue, resulting in chronic inflammation. In some cases, this leads to more and more thyroid tissue being lost and replaced by connective tissue.

It is not clear why the immune system makes this mistake. Genetic factors probably play a role: Experts assume that people with certain genes can develop these problems if too much iodine gets into their body. This might happen if they have to be injected with an iodine-containing contrast medium for a CT scan, for example. In day-to-day life, the iodine concentrations in our diets aren't high enough to cause these problems.

Hashimoto's disease affects an estimated 4 out of 1,000 women and 1 out of 1,000 men. It is the most common cause of an underactive thyroid in Germany and other countries. Most of those affected get it between the ages of 30 and 50. But it can occur in children and older people too.

People with Hashimoto’s disease often still have normal levels of thyroid hormones in their blood to start with, even though cells in the thyroid gland are dying. This is because the rest of the thyroid tissue can produce more hormones. But the tissue that’s still working properly needs to grow in order to keep the hormone levels normal. As a result, the thyroid is often bigger than normal at the beginning of the disease (this swelling is called a “goiter”).

At some point, only very little of the thyroid tissue remains and the body can't keep up. and the body can’t produce enough thyroid hormones any more. Then not enough thyroid hormones are produced. This leads to symptoms that are typical of an underactive thyroid.

In rare cases, people with Hashimoto’s disease have an overactive thyroid for a short time at the beginning of the illness. The symptoms include a rapid heartbeat, agitation and increased sweating. This is because hormones stored in the thyroid tissue are suddenly released into the body when the tissue dies.

If your doctor thinks you might have a thyroid problem like Hashimoto's disease, they will ask about your symptoms and examine the thyroid by feeling your neck. And they will often do an ultrasound scan of your thyroid.

The only way to know for sure whether you have a hormone disorder is by doing blood tests. The tests measure the levels of various thyroid hormones in your blood. These include the thyroid hormones themselves and the thyroid-stimulating hormone (TSH). TSH is produced in the pituitary gland in the brain. It controls the function of the thyroid gland.

These blood tests alone are not enough to detect hypothyroidism. Another test can help to find out whether the cause is Hashimoto's disease. It can detect certain antibodies to the thyroid tissue. Your body makes these antibodies due to an abnormal reaction of the immune system and they can be detected in the blood of most people who have Hashimoto's disease.

Because Hashimoto’s disease can occur in combination with other autoimmune diseases, further examinations are sometimes needed – for instance, to test for gluten intolerance (celiac disease) or diabetes.

When Hashimoto’s disease leads to an underactive thyroid, it’s important to get treatment. If it’s left untreated, complications such as cardiovascular (heart and blood vessel) disease can arise over the long term. Seizures, difficulty concentrating, memory problems, confusion and even comas are also possible but extremely rare.

It is not possible to treat the factors that caused the Hashimoto’s disease to develop. But if the inflammation results in an underactive thyroid, you can make up for the lack of T4 thyroid hormone (also known as “thyroxine”) by taking medication called levothyroxine or L-thyroxine. This medication is transformed into a thyroid hormone inside the body to keep the hormone levels within the normal range. The symptoms then usually go away completely. But it takes about two to three months for the hormone levels to return to normal.

Taken at the right dose, side effects are very rare. The dose is determined based on the person’s exact hormone levels, their body weight and other factors. If the dose is too high, it can cause agitation. So the hormone levels are checked regularly during the first few weeks of treatment. If necessary, the dose is changed. After that, the hormone levels usually only have to be checked once a year.

Sometimes treatment is also recommended for Hashimoto’s disease if antibodies are detected in the blood. This is known as “subclinical hypothyroidism.” In these cases, the thyroid gland still manages to make enough hormones, but only because the pituitary gland stimulates it to make more. The treatment is offered in order to prevent symptoms developing.

When people are ill or need medical advice, they usually go to see their family doctor first. Information about health care in Germany can help you to navigate the German health care system and find a suitable doctor. You can use this list of questions to prepare for your appointment.