Medicines
Discover all available medicines and treatments
Discover all available medicines and treatments
Brand: Tapazole, Thiamazole, Favistan, Mercazol
Methimazole is an antithyroid medication used to treat hyperthyroidism (overactive thyroid). It belongs to the thionamide class of drugs and works by inhibiting the synthesis of thyroid hormones within the thyroid gland. This helps to reduce the levels of circulating thyroid hormones, bringing them back to a normal range and alleviating symptoms of hyperthyroidism such as rapid heart rate, weight loss, anxiety, and tremors.
Used to treat hyperthyroidism, including Graves' disease.
Severe liver injury, including liver failure and death, has been reported with methimazole. Cholestatic jaundice may occur during the first few months of therapy. Patients should be instructed to report any symptoms of liver injury (e.g., fatigue, weakness, malaise, anorexia, nausea, vomiting, yellowing of the skin or whites of the eyes, dark urine). Methimazole should be discontinued if liver injury occurs.
Outcome:
Increased risk of bleeding
Mechanism:
Methimazole may inhibit the metabolism of warfarin.
Outcome:
Increased risk of hypothyroidism
Mechanism:
Additive effects on thyroid suppression.
Outcome:
May decrease effectiveness of methimazole
Mechanism:
Iodine can counteract the effects of methimazole.
Most likely new formulation: sustained-release formulation (2026, 60% confidence)
Based on current usage trends and clinical trial data, there is a low (5%) likelihood of significant regulatory changes for methimazole in the next 5 years.
Antithyroid Agent
Thionamide