Hypothyroidism is the decrease in the production of T3 and T4 hormones by the thyroid, resulting in symptoms such as tiredness, weakness and malaise, dry and rough skin, hair loss or weight gain.
The cause of hypothyroidism can be autoimmune, or occur due to iodine deficiency or changes in the pituitary gland in the brain that produces the hormone TSH, which stimulates the thyroid to produce T3 and T4.
The treatment of hypothyroidism is carried out by an endocrinologist and normally involves the use of medicines, such as levothyroxine, to replace thyroid hormones.
See with Dr. Leonardo Grossi more details about hypothyroidism:
Symptoms of hypothyroidism
The main symptoms of hypothyroidism are:
- Headache, muscles and joints;
- Irregular menstruation;
- Fragile, brittle nails;
- Rough and dry skin;
- Swollen eyelids;
- Hair loss, thinner, dry and dull hair;
- Heartbeat slower than normal;
- Excessive tiredness;
- Difficulty concentrating or poor memory;
- Decreased libido;
- Weight gain without apparent cause.
Furthermore, in some cases the person may experience personality changes, depression and dementia, however these symptoms occur in people who have very low levels of T3 and T4. Know how to identify all the symptoms of hypothyroidism.
In the case of children, hypothyroidism can also interfere with development, so that in adolescence they can have delayed puberty and short stature, for example.
How to know if it is hypothyroidism
To find out if it is hypothyroidism, the endocrinologist evaluates the symptoms presented by the person and the health and family history of hypothyroidism, in addition to carrying out a physical examination by palpating the thyroid.
Furthermore, to confirm the diagnosis of hypothyroidism, the doctor must order blood and imaging tests.
Make an appointment with the nearest endocrinologist to evaluate the possibility of hypothyroidism:
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Tests for hypothyroidism
The main tests to diagnose hypothyroidism are:
- Thyroid hormonessuch as T3 and T4, which are normally decreased;
- TSH dosagewhich is normally increased;
- Thyroid ultrasoundwhen nodules are noted during palpation of the thyroid.
In addition, the doctor may recommend testing for antithyroid antibodies, such as anti-thyroid peroxidase (anti-TPO), or thyroid mapping. See all tests that evaluate the thyroid.
It is also possible for the person to perform a thyroid self-examination to identify any changes, especially nodules.
Types of hypothyroidism
The main types of hypothyroidism are:
1. Primary hypothyroidism
Primary hypothyroidism occurs when the thyroid gland itself is unable to produce adequate amounts of the hormones T3 and T4.
Generally, this type of hypothyroidism is related to iodine deficiency.
2. Secondary or central hypothyroidism
Secondary hypothyroidism, also called central hypothyroidism, happens when the thyroid gland functions normally, but the pituitary gland does not produce enough TSH hormone or the hypothalamus does not produce enough TRH.
The hormone TRH (thyrotropin-releasing hormone) stimulates the pituitary gland to produce TSH (thyroid-stimulating hormone), which stimulates the thyroid gland to produce the thyroid hormones, T3 and T4.
3. Tertiary hypothyroidism
Tertiary hypothyroidism occurs due to a deficiency in the production of the hormone TRH by the pituitary gland, which affects the production of TSH by the pituitary gland.
4. Subclinical hypothyroidism
Subclinical hypothyroidism is characterized by normal levels of T4 and increased TSH, and the person usually presents few or no symptoms of hypothyroidism.
Even when there are no symptoms involved, the doctor may recommend the use of medications because these can help reduce the risk of cardiovascular problems, which can be important for people who are overweight or have high cholesterol or diabetes.
5. Congenital hypothyroidism
Congenital hypothyroidism occurs when the thyroid gland is unable to produce adequate amounts of thyroid hormones, such as T3 and T4, which are present from birth.
If this type of hypothyroidism is not detected in the first week after birth, the child may have neurological changes, with a risk of developing mental retardation. See more about congenital hypothyroidism.
6. Hypothyroidism in pregnancy
Hypothyroidism in pregnancy is generally caused by autoimmune changes, called Hashimoto’s thyroiditis, in which the immune system itself produces antibodies that attack and destroy thyroid cells as if they were foreign to the body.
This type of hypothyroidism must be treated to avoid problems for the woman and the baby.
Read too: Hashimoto’s thyroiditis: what it is, symptoms, causes and treatment
Hypothyroidism can also occur postpartum, a few months after the birth of the baby, on a temporary basis and which also requires careful treatment.
Possible causes
The main causes of hypothyroidism are:
- Iodine deficiency;
- Tireoidite de Hashimoto;
- Radioactive iodine therapy on the thyroid;
- Radiotherapy to the head or neck area, or to the brain;
- Thyroid surgery;
- Tumor in the pituitary or hypothalamus.
Furthermore, the use of medications such as lithium, amiodarone, thalidomide, phenytoin, phenobarbital, carbamazepine, interferon or imatinib, for example, can increase the risk of hypothyroidism.
It is important that the endocrinologist is consulted so that the cause of hypothyroidism can be identified and treatment can be initiated.
How the treatment is carried out
Treatment for hypothyroidism must be carried out under the guidance of an endocrinologist, who may indicate:
1. Use of medications
The use of medications, such as levothyroxine, is recommended by the endocrinologist to replace the hormones that are normally produced by the thyroid gland, thus allowing blood levels to be maintained at normal values. See how to take levothyroxine.
The dose of the medication must be prescribed by the endocrinologist and may vary throughout the treatment according to the levels of T3 and T4 circulating in the blood.
Read too: 6 remedies to treat thyroid disease (and how to use them)
In some cases, your doctor may also recommend the use of iodine supplements.
2. Change in eating habits
Changes in eating habits usually involve the consumption of foods rich in fiber, antioxidants and healthy fats, such as Brazil nuts, oranges and eggs, for example. Check out more details about nutrition for hypothyroidism.
See how nutrition can improve thyroid function in the following video:
Signs of improvement or worsening
Signs of improvement in hypothyroidism appear approximately 2 weeks after starting treatment, with a decrease in tiredness and an improvement in mood. Furthermore, long-term treatment of hypothyroidism also helps control weight and reduce blood cholesterol levels.
Signs of worsening appear when treatment is not carried out correctly or when the dose of Levothyroxine is not adequate, with insomnia, increased appetite, palpitations and tremors, for example.
Possible complications
When hypothyroidism is severe and not treated correctly, it can cause myxedema characterized by fluid retention, encephalopathy, decreased body temperature, seizures, hyponatremia, hypoglycemia, arrhythmias, cardiogenic shock or respiratory failure.
The treatment of myxedema is carried out in hospital on an inpatient basis, as it is a medical emergency that can be life-threatening. See how myxedema is treated.
