Loading...
About 7% of Americans have active levothyroxine prescriptions. To shed light on patterns of levothyroxine use, researchers analyzed laboratory test and claims data for 111,000 U.S. adults who filled new prescriptions for levothyroxine between 2008 and 2018 and in whom thyroid-stimulating hormone (TSH) was measured within 3 months before levothyroxine initiation.
The mean TSH level at which levothyroxine was initiated was about 5.5 mIU/L throughout the study period. Overall, 8% of levothyroxine prescriptions were for people with overt hypothyroidism (elevated TSH and low free or total thyroxine levels), 61% were for people with subclinical hypothyroidism (elevated TSH but normal thyroxine levels), and 31% were for people with normal thyroid f…