May 04, 2011 -- Elderly patients taking levothyroxine for hypothyroidism may be at an increased risk for bone fractures, according to a new report released by the University of Toronto. A study published in the British Medical Journal found that individuals age 70 or older who were currently taking the synthetic form of the thyroid hormone thyroxine were 88 percent more likely to suffer a broken bone over a four-year period, compared to those who had terminated such treatment several years earlier. Levothyroxine is commonly prescribed to replace the hormones of which an underactive thyroid gland produces too little. Though the National Institutes of Health (NIH) lists many possible side effects of such a drug regimen, until now increased fracture risk has not been one of them.
