Definition

Hypothyroidism is a medical condition characterized by an underactive thyroid gland, which fails to produce sufficient amounts of thyroid hormones. The thyroid hormones play a critical role in regulating the body’s metabolism, growth, development, and functioning of various organs and systems.

Causes

Hypothyroidism can commonly occur due to:

  • Autoimmune diseases, such as Hashimoto’s thyroiditis, where the body’s immune system attacks the thyroid gland.
  • Iodine deficiency, as the thyroid gland needs iodine to produce thyroid hormones.
  • Thyroid surgery or radiation therapy, which may damage or remove the thyroid gland.
  • Certain medications, including lithium and amiodarone, which can affect thyroid function.
  • Genetic disorders or congenital conditions affecting the thyroid gland.

Symptoms

The signs and symptoms of hypothyroidism may vary widely, but commonly include:

  • Fatigue and weakness
  • Weight gain or difficulty losing weight
  • Depression and mood swings
  • Dry and coarse skin
  • Constipation
  • Muscle aches and stiffness
  • Increased sensitivity to cold
  • Brittle hair and nails
  • Irregular menstrual cycles

Diagnosis

A diagnosis of hypothyroidism is typically made by evaluating the patient’s symptoms, conducting a physical examination, and performing the following laboratory tests:

  • Thyroid-stimulating hormone (TSH) blood test to measure the levels of TSH, which is produced by the pituitary gland to stimulate the thyroid gland in response to low hormone levels.
  • Thyroid hormone (T4) blood test to determine the levels of the primary thyroid hormone.
  • Additional tests, such as thyroid antibodies or imaging scans, may be ordered to identify the underlying cause in certain cases.

Treatment

The treatment of hypothyroidism involves hormone replacement therapy, typically through oral administration of synthetic thyroid hormones such as levothyroxine. The dosage is adjusted based on the individual’s specific needs, aiming to restore normal thyroid hormone levels and alleviate symptoms. Regular monitoring and follow-up are necessary to ensure optimal hormone levels and adjust medication as needed. In cases where hypothyroidism is caused by underlying conditions, additional treatments may be required.