Drilldown: Medicines

Cetirizine (1) · Flecainide (1) · Levothyroxine (1) · Loratadine (1) · Metoprolol (1) · Montelukast (1) · Moxifloxacin (1) · Thyroid (desiccated) (1)

Armour Thyroid, NP Thyroid, Nature-Throid, WP Thyroid (1) · Avelox (oral/IV brand discontinued US); Vigamox, Moxeza (ophthalmic) (1) · Claritin, Alavert, Tavist ND (1) · Lopressor (tartrate), Toprol XL (succinate) (1) · Singulair (1) · Synthroid, Levoxyl, Tirosint, Unithroid, Euthyrox (1) · Tambocor (US brand discontinued) (1) · Zyrtec, Zyrtec-D (1)

Beta Blocker (1) · Cardioselective (β1) (1) · [[:Category:Antiarrhythmics|Antiarrhythmic (Vaughan-Williams class IC)]] (1) · [[:Category:Antiasthmatic_agents|Antiasthmatic]] (1) · [[:Category:Antibacterials|Antibacterial]] (1) · [[:Category:Antihistamines|Antihistamine]] (2) · [[:Category:Fluoroquinolones|Fluoroquinolone antibiotic]] (1) · [[:Category:H1_receptor_antagonists|Histamine H1 receptor antagonist (second-generation)]] (2) · [[:Category:Hormone_replacement|Hormone replacement]] (2) · [[:Category:Leukotriene_receptor_antagonists|Leukotriene receptor antagonist]] (1) · [[:Category:Thyroid_hormones|Thyroid hormone]] (2)

None (1) · Cardioselective β1-adrenergic antagonist. Selectivity is dose-dependent and partially lost at higher doses. (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) · '"`UNIQ--vote-00000391-QINU`"' Minimal CYP metabolism; mostly renally cleared unchanged. Cetirizine is the active racemate; levocetirizine is the active R-enantiomer marketed separately'"`UNIQ--ref-00000392-QINU`"'. (1) · '"`UNIQ--vote-0000061E-QINU`"' Less reliably anticholinergic than first-generation H1s; minimal antiemetic effect. Desloratadine (Clarinex) is the active enantiomer-of-metabolite version marketed as a Rx alternative. (1) · '"`UNIQ--vote-00000D7A-QINU`"' Substantial QT-interval prolongation — the most QT-prolonging fluoroquinolone — limits use in patients on other QT-prolonging agents or with electrolyte abnormalities'"`UNIQ--ref-00000D7B-QINU`"'. (1) · '"`UNIQ--vote-0000113A-QINU`"' Concomitant β-blocker or CCB is required when used for AF to prevent 1:1 atrial flutter conduction (flecainide can slow atrial rate to a level where AV conduction allows dangerous ventricular rates). CYP2D6 substrate'"`UNIQ--ref-0000113B-QINU`"'. (1)

'"`UNIQ--vote-00000018-QINU`"', '"`UNIQ--vote-00000019-QINU`"' (1) · '"`UNIQ--vote-00000033-QINU`"', '"`UNIQ--vote-00000034-QINU`"', '"`UNIQ--vote-00000035-QINU`"' (1) · '"`UNIQ--vote-0000015B-QINU`"', '"`UNIQ--vote-0000015C-QINU`"', '"`UNIQ--vote-0000015D-QINU`"' (1) · '"`UNIQ--vote-00000393-QINU`"', '"`UNIQ--vote-00000394-QINU`"', '"`UNIQ--vote-00000395-QINU`"' (1) · '"`UNIQ--vote-000004F5-QINU`"', '"`UNIQ--vote-000004F6-QINU`"', '"`UNIQ--vote-000004F7-QINU`"', '"`UNIQ--vote-000004F8-QINU`"', '"`UNIQ--vote-000004F9-QINU`"' (1) · '"`UNIQ--vote-0000061F-QINU`"', '"`UNIQ--vote-00000620-QINU`"' (1) · '"`UNIQ--vote-00000D7C-QINU`"', '"`UNIQ--vote-00000D7D-QINU`"', '"`UNIQ--vote-00000D7E-QINU`"', '"`UNIQ--vote-00000D7F-QINU`"', '"`UNIQ--vote-00000D80-QINU`"', '"`UNIQ--vote-00000D81-QINU`"' (1) · '"`UNIQ--vote-0000113C-QINU`"', '"`UNIQ--vote-0000113D-QINU`"', '"`UNIQ--vote-0000113E-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) · 10 mg PO once daily (1) · 10 mg PO once daily (5 mg in older adults or if sedation occurs) (1) · 10 mg PO once daily in the evening (adults); 4-5 mg in children (1) · 25–50 mg BID (tartrate); 25–100 mg daily (succinate); 12.5 mg daily in HFrEF (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) · 400 mg PO/IV once daily (1) · 50 mg PO BID; titrate to 100-200 mg BID; pill-in-pocket 200-300 mg PO single dose for AF conversion (1)

10 mg tablets; 4 mg, 5 mg chewables; 4 mg granules (1) · 10 mg tablets; 5 mg ODT and chewables; 1 mg/mL oral syrup; combo Claritin-D (with pseudoephedrine, behind-counter) (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) · 400 mg tablets; 400 mg/250 mL IV; 0.5% ophthalmic solution (1) · 5 mg, 10 mg tablets; 5 mg, 10 mg chewables; 1 mg/mL oral syrup; OTC (1) · 50, 100, 150 mg tablets (1) · Tartrate: 25, 50, 100 mg tabs; 1 mg/mL IV. Succinate ER: 25, 50, 100, 200 mg. (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:

Search

IV (3) · Oral (8) · topical ophthalmic (1)

1-3 hours (slower onset than cetirizine; symptom relief somewhat less) (1) · 1–2 h (PO); immediate (IV) (1) · 30-60 minutes (1) · AF conversion within hours of single PO dose (1) · Bronchodilation within 1-2 hours; full controller effect 1-2 weeks (1) · Hours (1) · TSH normalization 4-8 weeks (1) · TSH normalization 4-8 weeks; symptomatic improvement weeks to months (1)

12 hours (1) · 24 hours (4) · 6–12 h (tartrate); 24 h (succinate) (1) · Steady-state at 4-6 weeks (2)

2.7-5.5 hours'"`UNIQ--ref-0000015E-QINU`"' (1) · 3–7 h (1) · 8-10 hours (longer in elderly and renal impairment)'"`UNIQ--ref-00000396-QINU`"' (1) · T4 ~7 days; T3 ~1 day'"`UNIQ--ref-0000001A-QINU`"' (1) · ~12 hours'"`UNIQ--ref-00000D82-QINU`"' (1) · ~14 hours (adults); longer in elderly and renal impairment'"`UNIQ--ref-0000113F-QINU`"' (1) · ~7 days (euthyroid); longer in hypothyroidism (~9-10 days), shorter in hyperthyroidism'"`UNIQ--ref-00000036-QINU`"' (1) · ~8 hours (parent); ~28 hours (desloratadine, the active metabolite, marketed separately as Clarinex)'"`UNIQ--ref-00000621-QINU`"' (1)

40-80% (oral); reduced by food, calcium, iron, PPIs, fiber; take fasting with water'"`UNIQ--ref-00000037-QINU`"' (1) · High (oral); not significantly affected by food'"`UNIQ--ref-00000397-QINU`"' (1) · High (oral; food prolongs absorption modestly)'"`UNIQ--ref-00000622-QINU`"' (1) · Variable; reduced by food, calcium, iron, PPIs'"`UNIQ--ref-0000001B-QINU`"' (1) · ~50% (1) · ~64% (oral; not significantly affected by food)'"`UNIQ--ref-0000015F-QINU`"' (1) · ~90% (oral)'"`UNIQ--ref-00001140-QINU`"' (1) · ~90% (oral; not affected by food but reduced by divalent cations)'"`UNIQ--ref-00000D83-QINU`"' (1)

'''Avoid in pregnancy where alternatives exist''' (animal cartilage toxicity).<sup class="pcp-cn" title="This claim needs a citation.">&#91;[[Pharmacopedia:Citation needed|citation&nbsp;needed]]&#93;</sup> (1) · Category C (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) · Generally considered safe; pregnancy registries do not show increased major malformation risk.<sup class="pcp-cn" title="This claim needs a citation.">&#91;[[Pharmacopedia:Citation needed|citation&nbsp;needed]]&#93;</sup> (1) · Generally considered safe; widely used. Levocetirizine (the R-enantiomer) is an alternative with similar safety.<sup class="pcp-cn" title="This claim needs a citation.">&#91;[[Pharmacopedia:Citation needed|citation&nbsp;needed]]&#93;</sup> (1) · Generally considered safe; widely used. Loratadine and cetirizine are the most-recommended 2nd-gen H1s in pregnancy and lactation.<sup class="pcp-cn" title="This claim needs a citation.">&#91;[[Pharmacopedia:Citation needed|citation&nbsp;needed]]&#93;</sup> (1) · Synthetic levothyroxine is the standard-of-care in pregnancy; desiccated thyroid use in pregnancy is not well studied.'"`UNIQ--ref-0000001C-QINU`"' (1) · Use in fetal SVT (transplacental antiarrhythmic therapy) is established; otherwise weigh against alternatives.<sup class="pcp-cn" title="This claim needs a citation.">&#91;[[Pharmacopedia:Citation needed|citation&nbsp;needed]]&#93;</sup> (1)

OTC in US (2) · Rx-only in US (1) · [[USLegal:Prescription only|Rx-only]] in US (2) · [[USLegal:Prescription only|Rx-only]] in US. '''Contraindicated in structural heart disease''' — CAST trial (1989) showed increased mortality from class IC agents in patients with prior MI; modern use is limited to structurally normal hearts'"`UNIQ--ref-00001141-QINU`"' (1) · [[USLegal:Prescription only|Rx-only]] in US. '''FDA Boxed Warning (2020):''' neuropsychiatric events including agitation, depression, sleep disturbance, and suicidal thoughts; benefit-risk should be reassessed regularly'"`UNIQ--ref-00000160-QINU`"'. (1) · [[USLegal:Prescription only|Rx-only]] in US. Carries the same fluoroquinolone-class '''Boxed Warnings''' as ciprofloxacin/levofloxacin'"`UNIQ--ref-00000D84-QINU`"' (1)