Hypothyroidism Signs Symptoms Causes Treatment Medication

Are you feeling sudden tiredness these days without any apparent reason, experiencing dryness of skin and frequent constipation? All these could be early indications of underactive thyroid gland.

Underactive thyroid, also called hypothyroidism is a common disorder which is prevalent in India. In hypothyroidism women or older people tend to suffer more than men. Understanding this serious condition in detail would help in its effective management.

What is Hypothyroidism?

Hypothyroidism is an under active thyroid. It is a disorder in which the thyroid gland does not produce enough thyroid hormones.
In this condition, human body lacks the optimum level of the thyroid hormones triiodothyronine (T3) and thyroxine (T4). These hormones regulate the vital body functions like Metabolic, heart rate, body weight, body temperature, LDL-bad cholesterol levels, etc. A normal human body should have these hormones in an equilibrium state. Appropriate balance of T3 and T4 hormones is regulated by both the pituitary gland and hypothalamus, in coordination.

The major role of the thyroid gland is to produce the two hormones T3 and T4, which requires many resources, reactions and events. When any of the requirements are not met with, the gland fails to produce adequate quantity of hormones. When the production of thyroid hormones fall below the body's normal need, certain signs and symptoms are exhibited, and this Cancer condition is called hypothyroidism. hypothyroidism is a more frequent dysfunction disorder of thyroid.

Hypothyroidism is of two types viz. primary and secondary hypothyroidism. Primary hypothyroidism is caused due to disorders of the thyroid gland. Secondary hypothyroidism is caused by disorders of the hypothalamus and pituitary gland, thereby leading to decreased secretion of thyroid stimulating hormone (TSH). Thyroid Stimulating Hormone (TSH)is the hormone responsible for stimulating production of thyroid hormones by the thyroid gland. Major causes of secondary hypothyroidism are the pituitary adenomas, radiotherapy and surgery.

What causes hypothyroidism
Hypothyroidism is generally more common in people who are already suffering from autoimmune disorders. One of the possible causes is presence of high fat cell deposition in the body, which produces leptin that leads to increased production of TSH. Elevated TSH levels in the blood indicate less amount of the thyroid hormones because of poor working of the thyroid gland.

Some of the common causes of hypothyroidism are explained below:
1. Hashimoto's thyroiditis This is an autoimmune disorder of the thyroid gland. It is the most common cause of underactive thyroid. In this condition, the thyroid cells are identified as foreign by the body and thus are under constant attack by the immune system. Autoimmune thyroiditis can begin suddenly or it can develop slowly over years with higher incidence occurring in women of childbearing age.
2. Thyroidectomy or radiation therapy Radiation is used for the treatment of overactive thyroid or thyroid cancer. Thyroidectomy is a surgical procedure used to remove some part or all of the gland. Goiter, which is a condition of enlargement of the thyroid gland can be treated by thyroidectomy. Thyroidectomy slows down or inhibits the production of thyroid hormones. The after-effects of radiation therapy on thyroid hormones might develop gradually without apparent signs and symptoms until several years.
3. Severe lodine Deficiency lodine deficiency is the most common cause of primary hypothyroidism. The trace element iodine is required by the body for making thyroid hormones. The iodide taken up by the thyroid gland eventually oxidizes to iodine with the help of enzymes thyroid peroxidase. The iodine further goes through a series of reactions within the thyroid gland for the production of thyroxine (T4) and triiodothyronine (T3).
4. Central hypothyroidism Central hypothyroidism is caused due to insufficient thyroid gland stimulation by thyroid stimulating hormone (TSH), occurring from pituitary gland or hypothalamus dysfunction. Both these glands produce hormones that influence thyroid hormone production and also play a part in the central nervous system.

The most common cause of hypothyroidism is known to be chronic autoimmune thyroiditis (Hashimoto's thyroiditis), which is characterised by inflammation and damage to the thyroid tissue. This causes thyroid to either partly or completely fail to synthesise the required quantities of thyroid hormones. The secondary causes of hypothyroidism include:
Surgical removal of the thyroid gland either for hyperthyroidism or thyroid cancer
A deficiency in dietary iodine consumption
Congenital thyroid absence, failure or defect .

Signs and symptoms of Hypothyroidism
The nature and severity of the symptoms of thyroid disorders vary from person to person. They are also dependent on the amount of decrease in thyroid hormones and the duration of time it has been present. For most patients, the symptoms are mild and can often be confused with other problems such as the natural aging process, menopause and stress. This is why, many patients remain undiagnosed and untreated for years. The symptoms may include a few or many of the following:
Fatigue, muscle swelling or cramps
Tingling in the fingers
Loss of equilibrium
Weight gain
Dry skin and cold intolerance
Yellow skin
Constipation
Depression
Goiter (enlarged thyroid causing a lump in the neck)
Decreased concentration
Infertility or miscarriages
Myxedema fluid infiltration of tissues causing puffiness (mainly on face) .

When does hypothyroidism get confirmed?

When the patient has majority of the symptoms and also presents with an increased levels of TSH with decreased levels of FT3 and Free Thyroxine Ft4. This is true in 98% of the cases of hypothyroidism, though in some cases, the same may not be met with fully.

Treatment for hypothyroidism
Since hypothyroid patients are deficient in thyroid hormones, they are treated with chemically synthesised hormones. Synthetic supplements of the hormone, T4 also called as thyroxine, is given to hypothyroid patients, which is available on prescription in medical stores. Thyroxine hormone tablet is known to be safe and people take it for decades without any documented side effects .

Its effectiveness may be decreased due to the patient's age or by interactions with other drugs. Therefore, it is essential that the physician be informed about any other medications the patient may be taking. The dosage required depends on the magnitude of the deficiency, weight and age of the patient (% age loss of thyroid activity).

The physician aims to bring the elevated TSH levels within the normal range by varying the dosage, using blood tests results as a guide. Once blood tests confirm that the patient is on the correct dose of medication, follow-ups of hormone levels can be done once in six months initially and then annually.

How long should thyroxine supplementation be continued?
Thyroxine supplement is basically thyroid hormone synthesised and packed in convenient doses of 25, 50 and 100 mg. In majority of the cases, thyroid hormone supplementation is for life. In some cases, mild hypothyroid symptoms may resolve and the patient might be withdrawn from the dose. A hypothyroid individual may need any where from 25 mg to 200 mg depending on severity of the condition

Thyroid function tests are then carried out and if thyronormalcy is indicated, the medication may be frozen, reduced or withdrawn completely.

Leading a normal life Once the patient is put on appropriate medication after hypothyroidism is diagnosed, the patient no more has thyroid hormone deficiency and hence all the associated problems should reduce substantially. The patient should be regular in taking the recommended medicines in the correct dosage and frequency. Intake in excess of the recommended dosage can also cause discomfort.

Did You Know the fact?
Many thyroid patients are prescribed tonics and high calorie diets when the clinician is not able to diagnose the thyroid problem.

What is Secondary hypothyroidism?
Secondary hypothyroidism is not a thyroid disorder, but a pituitary gland disorder. TSH is responsible in stimulating cells of the thyroid gland to produce its hormones. When the pituitary fails to synthesise the desired quantity of TSH there is a simultaneous deficiency of thyroid hormones in the body. Such patients will have all the signs and symptoms of hypothyroidism, but will not have an elevated TSH level and hence, may not be diagnosed in time. In management, through thyroxine, the blood tests should be carefully interpreted.