September 3, 1999
Thyroid
Question from Metairie, Louisiana, USA:
My Type 1 18 year old (diabetic for 3 years) was recently diagnosed with hypothyroidism. He is now taking Synthroid [a brand of thyroid hormone]. Before the thyroid problem was diagnosed, he was using R and N, and was well controlled. After starting thyroid therapy, his blood sugars became high immediately after meals and low before the next meal. We have adjusted by substituting 1H for 1R before meals and he seems okay. Will increasing doses of Synthroid cause increasing highs after meals? Why didn’t after meal highs occur when his thyroid was normal?
Answer:
Occasionally insulin requirements increase after starting Synthroid to correct hypothyroidism, though I’m not aware of a specific increase after meals. Is it possible that his appetite has also increased so that his meals are bigger? Also, if he only has had diabetes for 3 years, it is possible that his pancreas is still failing. In any case, the most important thing to do is to adjust the insulin dose according to the blood sugars, which you are doing.
TGL
