Dexamethasone and Methimazole interaction
Dexamethasone and Methimazole: both prescribing labels flag this combination with the strongest language, such as a contraindication, a boxed warning, or an instruction to avoid it.
Do not combine without a prescriber's guidance. The label language below is the strongest FDA uses.
What the FDA labels say
From the Dexamethasone (Hemady) label · effective 2026-01-09
When concomitant administration of corticosteroids and levothyroxine is required, administration of corticosteroid should precede the initiation of levothyroxine therapy to avoid adrenal crisis.
In addition, patients with hypopituitarism, primary adrenal insufficiency, or congenital adrenal hyperplasia, altered thyroid function, or pheochromocytoma may be at risk for adverse endocrine events.
Considerations for Use in Patients with Altered Thyroid Function Metabolic clearance of corticosteroids is decreased in hypothyroid patients and increased in hyperthyroid patients.
Changes in thyroid status of the patient may necessitate a dose adjustment of the corticosteroid.
From the Methimazole label · effective 2026-07-06
In some cases, vasculitis resolved/improved with drug discontinuation; however, more severe cases required treatment with additional measures including corticosteroids, immunosuppressant therapy, and plasmapheresis.
Taking more than these two? Interactions stack. Check your whole list at once; it stays in your browser.
Open in the checkerNot medical advice. Interaction Checker quotes FDA label text and NIH fact sheets. Whether an interaction matters for you depends on doses, timing, kidney and liver function, and other conditions. Confirm with a pharmacist or prescriber.