Is Ashwagandha Safe with Methimazole?
Free · No account · based on published sources including NIH ODS, FDA drug labels, and peer-reviewed literature
Avoid combining Ashwagandha with antithyroid medications. If already using both, inform your endocrinologist. Ashwagandha may counteract the therapeutic effect of methimazole, leading to poor hyperthyroidism control. Thyroid levels should be monitored closely.
Why this interaction occurs
Methimazole works by suppressing thyroid hormone synthesis in hyperthyroid conditions. Ashwagandha stimulates thyroid hormone production, directly antagonizing the pharmacological intent of antithyroid therapy. This combination may result in inadequate disease control in patients with Graves disease or toxic goiter.
Evidence
Evidence level: moderate.
Reported safety data
The FDA’s adverse event reporting system (FAERS) has received 8,031 reports mentioning Methimazole. This reflects reported cases involving the medication in general — not confirmed causation, and not specific to the Methimazole + 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 Ashwagandha interactions → · All Methimazole interactions →
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Educational only — not medical advice.
Always confirm with your doctor or pharmacist.