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What is the thyroid used for?

The thyroid gland is an endocrine gland; it produces hormones that pass into blood. T4 (Thyroxine) and in smaller quantities T3. Hormones are essential to the development of children and all adults.THE ages, they are essential for good functioning of all the cells in our body. They control functionsbasic metabolism such as heart rate or blood pressureregulation temperature. To be healthy, Weavons need  that the level of hormones thyroid InThe blood is normal. This is the interest of the thyroid biological test (blood test) which will measure TSH, T4 and T3 (depending on the symptoms).

The production of hormones by the gland is mainly regulated by another hormone: TSH (Thyroid Stimulating Hormone). This is made by the pituitary gland, which is a small gland located at the base of the brain (behind the eye sockets). The pituitary gland has sensors sensitive to the levels of the hormones T3 and T4 in the blood. Overall, if the TSH is normal, it means that there is the right amount of hormones in the blood. We say that we are in Euthyroidism. 

How does the body control production

of hormones by the thyroid gland? 

Hyperthyroidism or Hypothyroidism? 

Hyperthyroidism is when there are too many hormones in the blood (T4 and T3).

The TSH will therefore be collapsed. At the start of hyperthyroidism, there is simply a decrease in TSH. 

Hypothyroidism is when there are not enough hormones T4 and T3 in the blood. TSH is very high. At the onset of hypothyroidism, there will only be a rise in TSH.

What are the possible causes of hyperthyroidism?

Production hormones in excess may arise from a benign tumor of the gland

(functional nodule or also called hot nodule).

Hyperthyroidism can be caused by stimulation of the gland by antibodies produced by our immune system (autoimmune disease), this is Graves' disease.

Rarely, the cause of hyperthyroidism will be excess TSH produced by a pituitary tumor. 

Transient hyperthyroidism accompanies inflammation of the gland (thyroiditis).

Finally, hyperthyroidism can be caused by improper intake of hormones in the form of medications.

What are the possible causes of hypothyroidism?

The most common cause is Hashimoto's disease, the thyroid gland is attacked by antibodies produced by our system.immune system, which will lead to inflammation of the gland. After a period during which hormone production is normal or even high, this production will gradually decrease due to the progressive destruction of the gland. The diagnosis of Hashimoto's thyroiditis is made by measuring anti-TPO antibodies. This disease is very often familial.

Another common cause of hypothyroidism is surgical removal of the entire gland.thyroid or a large part of it. 

Your doctorYou will be prescribed levothyroxine (T4) when the gland's production of hormones is insufficient. The drug levothyroxine replaces the gland's production. It is a reserve hormone (this means that we will store it) that the body will transform into T3 (very active hormone) depending on the body's needs. Once used, T3 is quickly degraded. Levothyroxine is usually very well tolerated and very well absorbed by the body provided it is taken on an empty stomach (this can be both in the morning when you get up and in the evening when you go to bed).

In rare cases it is helpful to take T4 and T3 but this should be decided by a thyroid specialist.

Why should I take hormonal treatment with Levothyroxine (like levothyrox for example)?

Needs of the body in Levothyroxine are different of a personto the other and will depend in particular on weight, age, musculature, the persistence of the production of hormones by the gland, the capacity for absorption of the hormone. through the intestine, taking other medications...

Most often, a dose of between 1.5 and 1.7 micrograms of Levothyroxine per kilogram of weight is required (example: for a person weighing 60 kg, the usual dose varies between 87.5 and 100 micrograms per kilogram of weight). day. 

What dosage of Levothyroxine do I need?

If the dose of medication plug is GOOD adapted (monitoring on the dosage of HRT), the side effects are very unusual. Hypersensitivity reactions (allergy to excipients or to Levothyroxine) have been reported exceptionally. There may be interference with other medications (iron, calcium, antiepileptic medication, estrogen). Finally, some medications will be more active when combined with taking Levothyroxine (certain anticoagulants). Any unusual symptoms while taking Levothyroxine should be reported to your GP.

What are the side effects caused by taking Levothyroxine?

It is very important to have enough hormones thyroid during pregnancy, because these Hormones are essential to the development of the baby and in particular of his brain.

It is therefore imperative to take Levothyroxine if you lack of hormones thyroid and monitor this socket by the dosage of TSH. On the other hand, you should not have too many hormones because this can have negative effects for the mother and the baby. 

I am pregnant, can I  take Levothyroxine?

Levothyroxine in drug form is found in breast milk, as is Levothyroxine produced by the thyroid gland. The important thing is that the treatment is well adapted. 

I am going to breastfeed my baby, can I take Levothyroxine?

In case of significant excess, there are many signs such as fatigue abnormal,  palpitations, digestive disorders, intolerance to heat, mood disorders (emotionality, irritability), sleep disorders, tremors, weight loss. At the beginning of hyperthyroidism, palpitations, sweaty hands and irritability are the most common.

What are the signs of excess thyroid hormones (hyperthyroidism)?
What are the signs of a lack of thyroid hormones (hypothyroidism)?

In the event of a significant and prolonged lack, the signs the most common are: abnormal fatigue, chilliness, weight gain, constipation, difficulty concentrating and thinking and hair loss.

If you still have all or a good part of your thyroid gland the symptoms who will gradually appear are those of hypothyroidism. If you n'have no more thyroid gland after an operation, the consequences of stopping treatment will be more serious and can go as far as coma.

What happens if I stop taking my Levothyroxine?

When treatment is well adapted, there is little variation in needs. Taking another medicine may change the useful dose of Levothyroxine for you. These medicines are mainly iron, calcium, magnesium, anti-gastric acidity products, pill contraceptive, hormonal treatment for menopause.

In the event of pregnancy, hormone needs increase by 50% on average because the fetus depends on the mother's hormones during the first five months.

If heart disease occurs (angina, heart attack, rhythm disturbance), it is sometimes necessary to reduce the dose of Levothyroxine.

When should I change my dose of Levothyroxine?

The dosage of TSH is sufficient to ensure that you are taking the correct dose of Levothyroxine. However, if you exhibit symptoms suggestive of hyperthyroidism or hypothyroidism, it will be necessary to combine the measurement of the free T4 level. TSH and T4 measurements are taken in the morning before taking Levothyroxine. 

What are the blood dosages necessary to monitor treatment with Levothyroxine?
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