Is Iodine Safe with Armour Thyroid?
Free · No account · based on published sources including NIH ODS, FDA drug labels, and peer-reviewed literature
Avoid high-dose iodine supplements (>500 mcg/day) while taking Armour Thyroid unless directed by your physician. Discuss any kelp, seaweed, or iodine-containing supplements with your provider.
Why this interaction occurs
Excess iodine can paradoxically inhibit thyroid hormone synthesis (Wolff-Chaikoff effect) or trigger thyrotoxicosis in susceptible individuals. In patients on desiccated thyroid, iodine excess can interfere with the predictable dosing and therapeutic stability of the medication.
Evidence
Evidence level: moderate.
Reported safety data
The FDA’s adverse event reporting system (FAERS) has received 159,660 reports mentioning Armour Thyroid. This reflects reported cases involving the medication in general — not confirmed causation, and not specific to the Armour Thyroid + supplement combination on this page.
FAERS reports are voluntary and cannot prove that a drug caused an event. Do not use report counts to assess the safety of this specific drug-supplement pair.
Frequently asked questions
Related interactions
All Iodine interactions → · All Armour Thyroid interactions →
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Educational only — not medical advice.
Always confirm with your doctor or pharmacist.