Final answer:
The major risks associated with prescribing levothyroxine include an increased risk of heart disease, breast and colon cancer, osteoporosis, macular degeneration, and psychological conditions such as depression and possibly dementia due to overdose or inappropriate prescribing.
Step-by-step explanation:
Levothyroxine is a synthetic form of thyroid hormone prescribed for the treatment of hypothyroidism. While it is essential for patients with thyroid hormone deficiency, there are major risks associated with its use. Overdose or inappropriate prescribing can lead to hyperthyroidism-like symptoms since levothyroxine essentially increases the levels of thyroid hormone in the body.
Possible severe side effects of excessive levothyroxine include heart disease, such as an increased risk of stroke or heart attack, due to the elevated metabolic rate placing additional strain on the heart. Osteoporosis is another risk, particularly in postmenopausal women, as too much thyroid hormone can interfere with bone regeneration and density. Some studies have also suggested a potential link between excessive thyroid hormone and an increased risk of breast cancer and colon cancer. Other concerns may include macular degeneration, impacting vision, and psychological conditions such as depression and possibly dementia.