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Drug Interactions Results
Drug interactions for the following 2 drug(s):
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levothyroxine
metformin
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Interactions between your selected drugs
levothyroxine ↔ metformin
Applies to: levothyroxine, metformin
MONITOR: The efficacy of oral hypoglycemic agents and insulin may be diminished by certain drugs, including thiazides and other diuretics, corticosteroids, estrogens, progestins, thyroid hormones, human growth hormone, gonadotropin-releasing hormone agonists, phenothiazines, atypical antipsychotics, sympathomimetic amines, protease inhibitors, phenytoin, megestrol, danazol, isoniazid, asparaginase, pegaspargase, diazoxide, temsirolimus, sucralfate oral suspension, as well as pharmacologic dosages of nicotinic acid and adrenocorticotropic agents. These drugs may interfere with blood glucose control because they can cause hyperglycemia, glucose intolerance, new-onset diabetes mellitus, and/or exacerbation of preexisting diabetes.
MANAGEMENT: Close clinical monitoring of glycemic control is recommended if these drugs are coadministered with antidiabetic agents. Likewise, patients should be observed for hypoglycemia when these drugs are withdrawn from their therapeutic regimen. Dose adjustments of the hypoglycemic agent may be required.
I am also on synthroid and metformin, I have been feeling the same as you for a few days. Maybe we both need to call our docs :)
I've been diagnosed with PCOS, and prescribed with Metformin for the same reasons, I feel amazing on it, at first I had a reaction (severe runs) but powered through and it is also what helped me fall pregnant. I am still on it now that I'm pregnant but from my experience, the metformin does not, or rather has not caused exhaustion for me, probably in fact the opposite. I think your doc needs to investigate if the two drugs are counter acting each other. As metformin on it's own certainly hasn't had that effect on me. Hope that helps.
Does thyroid medication cause insulin resistance?
forgot to mention I am on 500 mg 2x a day, and on .25 levothyroxine 1x a day and I weigh 310 pounds, Are these doses correct? My free t4 was .44 (.61-1.12) and now it is .67.