1 interaction was found for the drugs you selected.
LEVOTHYROXINE in Synthroid
may interact with CALCIUM CARBONATE in Calcium Carbonate Tablets
Calcium carbonate may decrease the absorption of levothyroxine by the body. Potentially, less levothyroxine could be available for the body to use. Levothyroxine could be less effective and the results of tests that measure thyroid function may be altered. If calcium carbonate must be used for long periods of time while levothyroxine is taken, blood levels of levothyroxine may need to be monitored closely to make sure that they stay within therapeutic ranges.
You may want to ask your healthcare provider about this potential interaction if you think you are having problems.
This interaction is poorly documented and is considered moderate in severity.
(Note: Not all drug interactions are known or reported in the literature, and new drug interactions are continually being reported. This information is provided only for your education and for you to discuss with your personal healthcare provider.)