Methimazole Tablet Strengths Available
Yes, both 15 mg and 30 mg preparations of methimazole are available as standard tablet formulations. 1
Available Tablet Strengths
According to the FDA drug label, methimazole tablets are manufactured and available in multiple strengths, though the specific strengths are not explicitly enumerated in the provided labeling information. However, the dosing guidelines clearly reference both 15 mg and 30 mg as standard doses used in clinical practice. 1
Standard Dosing Regimens Using These Strengths
The FDA-approved dosing for adults demonstrates the use of these preparations:
- Mild hyperthyroidism: Initial dose of 15 mg daily 1
- Moderately severe hyperthyroidism: Initial dose of 30-40 mg daily 1
- Severe hyperthyroidism: Initial dose of 60 mg daily 1
- Maintenance therapy: 5-15 mg daily 1
Clinical Evidence Supporting These Dose Strengths
Multiple high-quality studies have utilized both 15 mg and 30 mg methimazole preparations:
A 2015 prospective study directly compared methimazole 15 mg daily versus 30 mg daily as initial therapy for moderate to severe Graves' disease, demonstrating that both dose strengths are commercially available and clinically utilized. 2
A 1986 study treated patients with single daily doses of either 15 mg or 30 mg methimazole, with 93% and 91% achieving euthyroidism respectively, confirming both preparations exist and are effective. 3
Important Prescribing Considerations
The total daily dose is typically divided into 3 doses given at 8-hour intervals, though single daily dosing has also proven effective. 1, 3 The 15 mg dose causes fewer adverse effects requiring discontinuation compared to 30 mg (7.5% vs 14.8%). 2
For severe cases requiring doses above what single tablets provide, multiple tablets can be combined to achieve the prescribed dose (e.g., two 30 mg tablets for a 60 mg dose). 1