Methimazole
Sulfur-Containing Imidazole Derivatives
Sold as TAPAZOLE
- Drug class
- Sulfur-Containing Imidazole Derivatives
- Availability
- Prescription only
- Routes
- Oral
- Markets covered
- 2
- Products on record
- 10
- FDA reports (12 mo)
- 634
Overview
Plain-language summary, compiled from the cited regulatory records
Methimazole is a medication belonging to the drug class of sulfur-containing imidazole derivatives [1]. It is approved for use as an antithyroid agent [1].
This medication is available under various brand names. In the past 12 months, there have been 634 adverse event reports associated with methimazole [2]. The most frequently reported adverse events include off-label use, drug ineffectiveness, product use in an unapproved indication, dizziness, and diarrhea [2].
This is not medical advice. Consult a qualified healthcare professional.
Regulatory status by market
| Market | Regulator | Products | Last revision |
|---|---|---|---|
| CA Canada | Health Canada | 6 | December 24, 2025 |
| US United States | FDA | 4 | February 7, 2026 |
CACanada· Health Canada
6 products
Uses
TAPAZOLE® (methimazole tablets) is indicated in adults for: • The medical treatment of hyperthyroidism. Long-term therapy may lead to remission of the disease. • Amelioration of hyperthyroidism in preparation for subtotal thyroidectomy or radioactive iodine therapy.
• Use when thyroidectomy is contraindicated or not advisable. 1 Pediatrics Pediatrics (<18 years): No data are available to Health Canada; therefore, Health Canada has not authorized an indication for pediatric use. 4 Geriatrics).
How to take
USUnited States· FDA
4 products
Uses
INDICATIONS AND USAGE
Methimazole tablets are indicated:
In patients with Graves’ disease with hyperthyroidism or toxic multinodular goiter for whom surgery or radioactive iodine therapy is not an appropriate treatment option. To ameliorate symptoms of hyperthyroidism in preparation for thyroidectomy or radioactive iodine therapy.
How to take
Drug interactions
Known interactions involving Methimazole. Select one for details. This list is informational and not a complete interaction checker.
Interaction data compiled from DDInter (academic, CC-BY). Severity classification only - this is not a complete interaction checker and not medical advice.
Sources & citations
- [1]Health Canada (DPD) · 00015741 · revised December 24, 2025
- [2]FDA DailyMed · 06bb4bcc-5e47-48… · revised February 7, 2026 [PDF]
- [3]OpenFDA adverse-event reports (US), 12 months ending June 4, 2026.
Information on this page is compiled from public regulatory records. Drugvu is not affiliated with any regulator or pharmaceutical manufacturer. This is not medical advice. Always consult a qualified healthcare professional.