Drilldown: Medicines

Bisoprolol (1) · Dextromethorphan / Quinidine (1) · Nebivolol (1)

Bystolic (1) · Nuedexta (1) · Zebeta (1)

None (1) · Beta Blocker (2) · Cardioselective (β1) (1) · Cardioselective (β1) + vasodilator (1)

Highly β1-selective adrenergic antagonist. Greater selectivity than metoprolol or atenolol. (1) · The d-enantiomer is a highly β1-selective antagonist; the l-enantiomer triggers endothelial nitric-oxide–mediated vasodilation. Unique among beta blockers for this NO mechanism. (1) · '"`UNIQ--vote-00001580-QINU`"' First FDA-approved treatment for PBA. The 10 mg quinidine daily dose is far below antiarrhythmic levels but sufficient to nearly fully inhibit CYP2D6, the basis of the combination's pharmacokinetic rationale'"`UNIQ--ref-00001581-QINU`"'. (1)

'"`UNIQ--vote-0000059D-QINU`"' (1) · '"`UNIQ--vote-00000636-QINU`"', '"`UNIQ--vote-00000637-QINU`"', '"`UNIQ--vote-00000638-QINU`"' (1) · '"`UNIQ--vote-00001582-QINU`"' (1)

1 capsule (20/10 mg dextromethorphan/quinidine) PO once daily × 7 days, then 1 capsule BID (1) · 2.5–5 mg daily (HTN); 1.25 mg daily (HFrEF, slow titration) (1) · 5 mg daily (1)

2.5, 5, 10, 20 mg tabs (1) · 20 mg dextromethorphan HBr / 10 mg quinidine sulfate capsules (1) · 5, 10 mg tabs (1)

1 capsule BID (40 mg DXM / 20 mg quinidine per day) (1) · 20 mg/d (1) · 40 mg/d (1)

Oral (3)

None · Hours · 30-60 minutes · 1-2 hours · ~30 min · LDL lowering at 2 weeks, max by 4 weeks · ~1 hour · 15-30 minutes · 15–30 min · 1–2 h · 30–60 min · Antidepressant effect emerges over 1-2 weeks · BP and symptomatic LUTS improvement within 1-2 weeks · BP effect within 1-2 weeks · Clinical improvement within 24-72 hours · Days · Motor improvement over days at therapeutic dose · Over weeks · Postprandial glucose effect within days; HbA1c by 12 weeks · Sleep effect from first dose; antidepressant effect over 1-4 weeks

Other values:

Search

12 hours (1) · 24 h (2)

9–12 h (1) · Dextromethorphan substantially prolonged by quinidine's CYP2D6 inhibition (typical extensive metabolizers see ~10× higher AUC); quinidine ~6-8 hours'"`UNIQ--ref-00001583-QINU`"' (1) · ~10 h (CYP2D6 extensive metabolizers); up to 31 h (poor metabolizers) (1)

Increased substantially via CYP2D6 inhibition'"`UNIQ--ref-00001584-QINU`"' (1) · ~12% (extensive metabolizers); ~96% (poor metabolizers) (1) · ~90% (low first-pass) (1)

Category C (2) · Limited data; quinidine has been used in pregnancy as antiarrhythmic.<sup class="pcp-cn" title="This claim needs a citation.">&#91;[[Pharmacopedia:Citation needed|citation&nbsp;needed]]&#93;</sup> (1)

Rx-only in US (2) · [[USLegal:Prescription only|Rx-only]] in US. Caution with QT-prolonging medicines (quinidine itself is class IA antiarrhythmic, and the dose here, though sub-antiarrhythmic, still contributes to QT)'"`UNIQ--ref-00001585-QINU`"' (1)