The information provided here is meant to give you a general idea about each of the medications listed below. Only the most general side effects are included, so ask your doctor if you need to take any special precautions. Use each of these medications as recommended by your doctor, or according to the instructions provided. If you have further questions about usage or side effects, contact your doctor.

Hormonal Therapy

Hormones are chemical messengers that regulate specific body functions. They are produced by various glands in the body and enter the blood stream, where they travel to other tissues and exert their influence. Hormonal therapy is used in cancer treatment to augment or interfere with the activity of certain hormones that can influence the growth of tumors.

Hormonal therapy is an important adjunct for thyroid cancer. It is delivered in the form of thyroid hormone pills. Hormonal therapy is used both to treat the deficiency of thyroid hormone that occurs after the thyroid gland is removed or destroyed and to prevent or delay remaining bits of thyroid tissue from growing by suppressing thyroid-stimulating hormone (TSH) secreted from the pituitary gland.

There are several types of thyroid hormones which could be used:

  • Levothyroixine
  • Liothyronine—used postoperatively to prepare for radioiodine scan
  • Thyrotropin alfa—a synthetic thryoid stimulating hormone (TSH) used to prepare for scanning or for thyroglobulin blood level measurement

Effectiveness

Giving thyroid hormone seems to decrease the chance that remaining bits of thyroid tissue will grow. No one is sure how long patients should continue to be treated with thyroid hormone, however.

Side Effects and Possible Complications

Since the elderly may have an underlying heart, liver, or kidney disease, these hormone medications should be used with caution in this population.

  • You may notice a skin rash within the first few months of treatment with thyroid hormone.
  • You may lose more hair than usual within the first few months of treatment with thyroid hormone.
  • Levothyroxine or liothyronine may causes symptoms similar to overactive thyroid including rapid heart rate, insomnia, weight loss, sweating, flusing in the face, or diarrhea.
  • Thyrotropin alfa often causes nausea, muscle weakness, or headache.

Post-treatment Care

You’ll need to be monitored regularly and carefully to make sure that you are receiving an appropriate dose of thyroid hormone. Too little hormone will cause hypothyroidism, which has the following symptoms:

  • Weight gain
  • Cold intolerance (you constantly feel chilly when others are comfortable)
  • Dry skin
  • Dry hair
  • Low energy
  • Muscle or joint pains

Too much hormone can cause hyperthyroidism, which has the following symptoms:

  • Weight loss
  • Feeling overheated, sweaty
  • Diarrhea
  • Abdominal cramps
  • Chest pain
  • Nervousness
  • Feeling jittery or “hyper”