Drilldown: Medicines

None (1) · Levothyroxine (1) · Thyroid (desiccated) (1)

Armour Thyroid, NP Thyroid, Nature-Throid, WP Thyroid (1) · Rexulti (1) · Synthroid, Levoxyl, Tirosint, Unithroid, Euthyrox (1)

5HT1A activity than aripiprazole (1) · 5HT2A (1) · Atypical antipsychotic (1) · D2/5HT1A partial agonist with stronger α1A (1) · [[:Category:Hormone_replacement|Hormone replacement]] (2) · [[:Category:Thyroid_hormones|Thyroid hormone]] (2)

Partial agonist at D2 and 5HT1A. Antagonist at 5HT2A, α1A, α1B, α2C. More potent 5HT2A antagonism, 5HT1A partial agonism, and α1 antagonism (relative to D2 partial agonism) than aripiprazole, proposed to reduce akathisia and enhance affective/cognitive effects. (1) · Synthetic T4 (thyroxine); peripherally deiodinated to T3 (triiodothyronine), the active hormone. '"`UNIQ--vote-00000031-QINU`"' Narrow therapeutic index; brand-to-generic switches can shift TSH and require re-titration'"`UNIQ--ref-00000032-QINU`"'. (1) · '"`UNIQ--vote-00000016-QINU`"' Brand-to-brand and lot-to-lot variability in T3:T4 ratio is greater than with synthetic levothyroxine, which is why endocrine guidelines prefer the synthetic'"`UNIQ--ref-00000017-QINU`"'. (1)

Schizophrenia (FDA-approved 2015). Adjunctive treatment of major depressive disorder (2015). '''Agitation associated with dementia due to Alzheimer disease''' (FDA-approved May 2023, first agent specifically approved for this problem). Investigational for PTSD (combined with sertraline). (1) · '"`UNIQ--vote-00000018-QINU`"', '"`UNIQ--vote-00000019-QINU`"' (1) · '"`UNIQ--vote-00000033-QINU`"', '"`UNIQ--vote-00000034-QINU`"', '"`UNIQ--vote-00000035-QINU`"' (1)

1.6 mcg/kg/d in young healthy adults; 25-50 mcg/d in elderly or cardiac disease, titrated by TSH at 6-8 weeks (1) · 30 mg PO daily (1/2 grain); titrate by TSH at 6-8 weeks; 60 mg desiccated thyroid is approximately equivalent to 88-100 mcg levothyroxine (1) · Schizophrenia: 1 mg PO daily × 4 days, then 2 mg daily × 3 days, then 4 mg daily. MDD adjunct: 0.5-1 mg daily, increase to 2 mg max. AD agitation: 0.5 mg daily, titrate to 2-3 mg daily. (1)

0.25 mg, 0.5 mg, 1 mg, 2 mg, 3 mg, 4 mg tablets (1) · 15, 30, 60, 90, 120, 180, 240, 300 mg tablets (1/4 to 5 grains; 1 grain = 60 mg) (1) · 25, 50, 75, 88, 100, 112, 125, 137, 150, 175, 200, 300 mcg tablets; oral capsule and IV/IM also available (1)

None · Indication-specific · 40 mg/d · 10 mg/d · 20 mg/d · 80 mg/d · 10 mg/d (adults) · 100 mg/d · 4 g/d · 400 mg/d · 40 mg/d typical; up to 240 mg/d for Zollinger-Ellison · 5 mg/d · 50 mg/d · 600 mg/d · No fixed ceiling; titrate to clinical effect and tolerability with CDC opioid prescribing guidance constraints on morphine-milligram-equivalent (MME) totals · No fixed maximum; titrated to TSH target · TID per eye · Titrated to glucose; no fixed ceiling · Titrated to glucose; no fixed maximum · '''20 mg/day in adults >60 years''' per FDA's 2011-2012 QT-prolongation warning; 40 mg/day in adults ≤60

Other values:

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IV (1) · Oral (3)

TSH normalization 4-8 weeks (1) · TSH normalization 4-8 weeks; symptomatic improvement weeks to months (1) · Weeks for psychosis/depression; AD agitation benefit emerges over weeks (1)

Daily dosing (1) · Steady-state at 4-6 weeks (2)

T4 ~7 days; T3 ~1 day'"`UNIQ--ref-0000001A-QINU`"' (1) · ~7 days (euthyroid); longer in hypothyroidism (~9-10 days), shorter in hyperthyroidism'"`UNIQ--ref-00000036-QINU`"' (1) · ~91 hours (1)

40-80% (oral); reduced by food, calcium, iron, PPIs, fiber; take fasting with water'"`UNIQ--ref-00000037-QINU`"' (1) · Variable; reduced by food, calcium, iron, PPIs'"`UNIQ--ref-0000001B-QINU`"' (1) · ~95% (1)

First-line in pregnancy; dose typically increased 25-30% due to estrogen-driven rise in TBG and fetal demand. Lactation safe at physiologic doses.<sup class="pcp-cn" title="This claim needs a citation.">&#91;[[Pharmacopedia:Citation needed|citation&nbsp;needed]]&#93;</sup> (1) · Limited data; National Pregnancy Registry available (1) · Synthetic levothyroxine is the standard-of-care in pregnancy; desiccated thyroid use in pregnancy is not well studied.'"`UNIQ--ref-0000001C-QINU`"' (1)

Rx (1) · [[USLegal:Prescription only|Rx-only]] in US (2)