Methimazole: Difference between revisions
(Text replacement - "OR" to "'''OR'''") |
ClaireLewis (talk | contribs) |
||
(One intermediate revision by one other user not shown) | |||
Line 1: | Line 1: | ||
==Administration== | ==Administration== | ||
*Type: Antithyroid | *Type: Antithyroid | ||
*Dosage Forms: | *Dosage Forms: Tablet; 5mg, 10mg | ||
*Routes of Administration: Oral | *Routes of Administration: Oral | ||
*Common Trade Names: Tapazole | *Common Trade Names: Tapazole | ||
Line 54: | Line 54: | ||
<references/> | <references/> | ||
[[Category:Pharmacology]] | [[Category:Pharmacology]] | ||
[[Category:Endocrinology]] |
Latest revision as of 23:15, 22 September 2019
Administration
- Type: Antithyroid
- Dosage Forms: Tablet; 5mg, 10mg
- Routes of Administration: Oral
- Common Trade Names: Tapazole
Adult Dosing
- Thyroid storm: 60 to 80 mg PO daily
- Amiodorone-induced thyrotoxicosis: 40mg PO daily until patient is euthyroid (usually 3-6mo)
- Iodine-induced thyrotoxicosis: 20-40mg PO once
- Hyperthyroidism
- Initial: 10-20mg/day (mild), 30-40mg/day (moderate), 60mg/day (severe) in 1-3 doses
- Maintenance: 5-15mg/day
- 2nd-3rd trimester pregnancy: Use lowest dose needed to keep maternal total T3/T4 slightly above normal range for pregnancy, TSH suppressed, and free T4 at or slightly above upper limit of normal for nonpregnant women
Pediatric Dosing
- Hyperthyroidism:
- Initial: 0.2-0.5 mg/kg PO daily OR 0.4mg/kg PO daily in 3 divided doses
- Maintenance: 50% of initial dose
Special Populations
- Pregnancy Rating: D - see pregnancy dosing
- Lactation risk: Infant risk cannot be ruled out
- Renal dosing: no adjustment
- Hepatic dosing: no adjustment
Contraindications
- Allergy to class/drug
Adverse Reactions
Serious
- Agranulocytosis, aplastic anemia
- Vasculitis
- Pancreatitis
- Hepatotoxicity
Common
- Rash
Pharmacology
- Half-life: 2-28h
- Metabolism: Hepatic
- Excretion: Renal
Mechanism of Action
- Inhibits thyroperoxidase, thus blocking synthesis of thyroid hormones