NEWWEEK – A drug called levothyroxine, the second-most-commonly prescribed medication among older U.S. adults, has been linked to a higher risk of bone loss in a new study.
Levothyroxine is prescribed to treat hypothyroidism—an under-active thyroid—in approximately 23 million Americans, or 7 percent of the U.S. population, under various brand names, including Synthroid.
But scientists have found that the drug may put older adults at risk of losing bone mass, a risk factor for the bone disease osteoporosis.
Dr. Shadpour Demehri, co-senior author of the study and a professor of radiology at Johns Hopkins University, said in a statement:
“Our study suggests that even when following current guidelines, levothyroxine use appears to be associated with greater bone loss in older adults.”
Hypothyroidism is a common condition whereby the thyroid gland does not produce enough of the hormone thyroxine, leading to fatigue, weight gain, hair loss and other symptoms.
While hypothyroidism can lead to serious and potentially fatal complications without treatment, it is possible to have too much thyroid hormone: a condition called hyperthyroidism, which can lead to heart palpitations, high blood pressure, shakiness, anxiety, weight loss and an increased risk of bone fractures.
Lead author Dr. Elena Ghotbi, a postdoctoral research fellow at Johns Hopkins School of Medicine said:
“Data indicates that a significant proportion of thyroid hormone prescriptions may be given to older adults without hypothyroidism, raising concerns about subsequent relative excess of thyroid hormone even when treatment is targeted to reference range goals” …
