Hyperthyroidism is a condition caused by too much
thyroid hormone in the body. It occurs when the
thyroid gland produces more thyroid hormones than is
needed. The thyroid gland produces the thyroid
hormones triiodothryronine (T3) and thryroxine (T4).
T3 is the more active form, while T4 is partially
converted to T3 when released in the blood stream. The
thyroid hormones regulate metabolism throughout the
body. Grave's Disease , which is the most common type
of hyperthyroidism, is associated with enlargement and
dysfunction of the eye sometimes.
Causes
Although the exact cause of hyperthyroidism is
unknown, it is often associated with autoantibodies in
the blood which cause the thyroid to grow and excrete
excess thyroid hormone.
Grave's disease, also known as toxic diffuse goiter
and is the most common form of hyperthyroidism
affecting the entire thyroid gland. Grave's disease is
considered an autoimmune disorder (a condition in
which the body's immune system develops antibodies
against its own thyroid gland cells).
Hyperthyroidism may be caused by overactivity of
solitary or multiple benign nodules within the
thyroid. Individual or multiple nodules within the
thyroid may enlarge and begin producing excess amounts
of thyroid hormone. These nodules produce hormones,
even in the absence of TSH, and as such are not
affected by the normal mechanisms that control thyroid
hormone levels.
Symptoms
The symptoms of hyperthyroidism may include:
- Goiter (enlarged thyroid gland)
- Nervousness
- Anxiety
- Irritability
- Trembling hands
- Fatigue
- Sweating
- Insomnia
- Diarrhea
- Itchy skin
- Heart palpitations
- Heat intolerance
- Sweating
- Muscle Cramps
- Hair loss
- Increased bowel movements
- Decrease in menstrual periods
- Eye irritation
Treatment
The options for treatment, which will lower the amount
of thyroid hormone in your body, are medication,
radiation and surgery. Antithyroid drug therapy blocks
thyroid hormone production and usually has it under
control in several weeks.
Drug therapy includes using two types of drugs to
control the hyperthyroidism. Initially, the doctor will
prescribe either methimazole (Tapazole) or
propylthiouracil (PTU) pills which are antithyroid
agents.
Radiation therapy is an alternative if drug treatment
fails. The patient is given a capsule or a drink of
water containing radioactive iodine. After being
swallowed, the "radioiodine" is rapidly absorbed by the
overactive thyroid cells and over a period of several
weeks, the radioactive iodine damages the cells.
Surgical removal of all or part of the thyroid gland (thyroidectomy),
is usually used to treat very young patients with
Graves’ disease and older patients with diseased
thyroids. It cures the disease 90% of the time. The
risks associated with a thyroidectomy include nerve
damage and low thyroid levels.
