Introduction to the Endocrine System
The glands of the body are classified into two groups:
- Exocrine glands. The glands that release secretion through ducts. Sweat glands are classical examples.
- Endocrine glands. The glands pour secretion (hormones) directly into the blood as they are devoid of ducts. They are also known as ductless glands.
The endocrine system regulates and coordinates working of various organ systems. Endocrine system normally transmits their message with the aid of secretions known as hormones, which reach the target organ through arterial and lymphatic system.
Pituitary gland (see the diagram) is considered to be the master endocrine gland of the human body. It is responsible for controlling the functions of other endocrine glands. Functions of endocrinal glands of the human body are summarised below:
Incidence of thyroid diseases
Thyroid diseases are common throughout the world. In India, there is a significant rise in patients diagnosed with thyroid diseases. According to a data collected from various studies and surveys on thyroid disease, it has been estimated that about 42 million people in India suffer from thyroid diseases.
Disorders of the thyroid glands
- The thyroid gland is situated beneath the larynx and is the largest endocrine gland of the body (for position of the thyroid gland, see the diagram).
- The main role of thyroid is to control metabolism of the entire body. Thyroid produces two hormones thyroxine and calcitonin.
- Thyroxine is responsible for metabolism and thus influences the internal body temperature. If thyroxine is secreted in excess amount, it leads to exophthalamic goiter (hyperthyroidism). If it is secreted in low amounts the condition is myxoedema (hypothyroidism).
- It has important influence on the kidney and deficiency leads to decreased urinary output.
- Calcitonin is responsible for regulating calcium levels in the body. Disturbed function can lead to osteoporosis.
Synonym: Underactive thyroid disease.
- Disorder of the hypothalamus,
- Hashimoto’s thyroiditis,
- Medications like lithium (antidepressant),
- Pituitary gland damage or disorder
- Radiation therapy to the neck area,
- Radioactive iodine treatment,
- Thyroid surgery,
- Too little iodine in the diet.
- Primary hypothyroidism is generally caused by a dysfunction of the thyroid gland largely at itself.
- Secondary hypothyroidism occurs when any another diseases obstructs the thyroid gland ability to produce hormones in a coherent fashion.
Risk for Hypothyroidism
- Age (growing older)
- Autoimmune disorders (type 1 diabetes, multiple sclerosis, rheumatoid arthritis, celiac disease, Addison’s disease, pernicious anaemia, or vitiligo)
- Bipolar disorder
- Down syndrome
- Prematurely greying of the hairs
- Race (being white or Asian)
- Turner syndrome
Signs and Symptoms
- Changes in the menstrual cycle
- Dry hair and hair loss
- Dry skin
- Greater sensitivity to cold
- Slow heart rate
- Swelling of the thyroid gland (goiter)
- Unexplained weight gain or difficulty losing weight
- Carpal tunnel syndrome
- Cold hands and feet
- Extreme sleepiness
- Hoarse cry
- Little or no growth
- Low muscle tone (floppy infant)
- Persistent jaundice (yellowing of the skin and whites of the eyes)
- Poor feeding habits
- Puffy face
- Stomach bloating
- Swollen tongue
- Hypothyroidism is diagnosed by doing thyroid profile test.
- Thyroid-stimulating hormone (TSH) T4 (thyroxine) are determined in the laboratory.
- Lower-than-normal T4 levels usually confirm hypothyroidism. However, increased TSH levels may be seen in some patients while having normal T4 levels. This is known as subclinical hypothyroidism and is believed to be an early stage of the hypothyroidism.
If a patient is diagnosed hypothyroidism, the physician prescribes a synthetic thyroid hormone T4. Eltroxin and thyronorm are famous brands prescribed by the doctors.
Complications of Hypothyroidism
- Heart problems
- Joint pain
Synonym: Overactive thyroid disease.
- Benign tumours of the thyroid or pituitary gland,
- Excess iodine (iodine is needed to make T4 and T3),
- Graves’ disease (antibodies stimulate the thyroid to secrete too much hormone),
- Inflammation of the thyroid gland (thyroiditis causes T4 and T3 to leak out of the gland),
- Taking large amounts of tetraiodothyronine (through dietary supplements or medication).
- Tumours of the ovaries or testes
Signs and Symptoms
- Breast development in men,
- Difficulty in concentrating,
- Difficulty sleeping,
- Elevated blood pressure,
- Eyes may appear quite prominent (exophthalmos),
- Feel hungry,
- Feel restless,
- Hair loss,
- Hand tremors,
- Heat intolerance,
- Increased bowel movements,
- Irregular heartbeat,
- Irregular menstrual cycles,
- Itching ,
- Nausea and vomiting,
- Rapid heart rates,
- Sweat a lot,
- Weight loss.
- Computed Tomography Scan or Magnetic Resonance Imaging
- Lipid gram,
- Thyroid profile test,
- Thyroid scan,
- If a patient is diagnosed hypothyroidism, the physician prescribes antithyroid medications and radioactive iodine.
- Antithyroid medications inhibit the synthesis of thyroid hormone.
- Radioactive iodine effectively destroys the thyroid producing cells. Methimazole and neomercazole are typical drugs used in hyperthyroidism.
- Kanchnara is the drug of choice in treating goitre.
- Kanchnar Guggulu, two tablets, twice a day, along with decoction of the bark of the drug, six teaspoonfuls (30 ml), is recommended in the treatment of the disease. It is supplemented with Kachnar tvak Quatha.
- Guggul is an ideal drug in dealing with hyperthyroidism.
- Helps to Treat Thyroidism
- Treats Goitre
- Corrects Hormonal Imbalance
- Treats PolyCystic Ovarian Syndrome or Disease
- Corrects Anovulation, Amenorrhoea
- Treats Endometriosis and Fibroids
- Enhances Female Reproductive Health
- Promotes weight loss
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