In the latest study, researchers at McGill University in Montreal found that Metformin, a commonly used drug to treat type-2 diabetes, increases the risk of low thyroid-stimulating hormone level in patients with underactive thyroids. In this study, 74,300 patients were given either Metformin or sulfonylurea, over a 25-year study period. In patients with treated hypothyroidism, Metformin monotherapy was linked with 55% increased risk of low TSH levels as compared to the use of sulfonuylurea. Via Science World Report. Posted September 26, 2014.

Use of Metformin Tied to Risk of Low Thyroid Hormone Levels