Comparative Pharmacology
Head-to-head clinical analysis: LEVOTHYROXINE SODIUM INTRAVENOUS versus LEVOXYL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LEVOTHYROXINE SODIUM INTRAVENOUS versus LEVOXYL.
LEVOTHYROXINE SODIUM vs LEVOXYL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Synthetic T4 hormone that is deiodinated to T3, which binds to thyroid hormone receptors in the nucleus, regulating gene transcription and increasing metabolic rate.
Levothyroxine is a synthetic thyroid hormone (T4) that is deiodinated to triiodothyronine (T3) in peripheral tissues, binding to thyroid hormone receptors in the nucleus and increasing metabolic rate, protein synthesis, and oxygen consumption.
Initial adult dose: 25-50 mcg orally once daily, titrated by 12.5-25 mcg every 6-8 weeks based on TSH. Usual maintenance: 1.6 mcg/kg/day. Route: oral; IV dose is 50% of oral dose.
Initial adult dose: 25-50 mcg orally once daily; titrate by 12.5-25 mcg every 6-8 weeks based on TSH. Maintenance dose: 50-200 mcg orally once daily.
None Documented
None Documented
6-7 days (euthyroid); prolonged in hypothyroidism (9-10 days) and shortened in hyperthyroidism (3-4 days).
6-7 days in euthyroid patients; prolonged in hypothyroidism (9-10 days), shortened in hyperthyroidism (3-4 days); clinical steady-state after 6-8 weeks of consistent dosing.
Renal (approximately 50% as unchanged drug and conjugates); fecal (biliary excretion of conjugates, ~20-30%); minor pulmonary and dermal routes.
Renal (30-50% as unchanged drug and conjugates); fecal (biliary, 20-40% as conjugates); total clearance approximates 1-2 L/day in euthyroid patients.
Category A/B
Category C
Thyroid Hormone
Thyroid Hormone