Nuedexta Generic Name & Formulations
Dextromethorphan HBr 20mg, quinidine sulfate 10mg; caps.
Uncompetitive NMDA receptor antagonist and sigma-1 receptor agonist + CYP2D6 inhibitor.
Nuedexta Dosage and Administration
≥18yrs: 1 cap daily for 7 days, then (starting on Day 8) 1 cap every 12hrs. Reevaluate periodically.
<18yrs: not established.
Concomitant quinidine, quinine, or mefloquine. History of quinine, mefloquine, or quinidine-induced thrombocytopenia, hepatitis, bone marrow depression, lupus-like syndrome. During or within 14 days of MAOIs. Prolonged QT interval. Congenital long QT syndrome. History of torsades de pointes. Heart failure. Drugs that prolong QT interval and are CYP2D6 substrates (eg, thioridazine, pimozide). Complete AV block w/o pacemaker, or risk of complete AV block.
Nuedexta Boxed Warnings
Discontinue if quinidine-related thrombocytopenia occurs (continued use may cause fatal hemorrhage); do not restart. Risk of QT prolongation and torsades de pointes (eg, concomitant drugs that prolong QT interval or that are strong or moderate CYP3A4 inhibitors, left ventricular hypertrophy, LVD): do ECG at baseline and 3–4 hours after 1st dose; reevaluate ECG if risk factors for arrhythmia (eg, electrolyte abnormality, bradycardia, family history of QT abnormality) change during treatment. Correct hypokalemia, hypomagnesemia before starting. Discontinue if arrhythmias occur. Myasthenia gravis. History of falls. Consider genotyping for poor metabolizers of CYP2D6. History of drug abuse (monitor). Severe renal or hepatic impairment. Elderly. Pregnancy. Nursing mothers.
See Contraindications. May cause serotonin syndrome with concomitant SSRIs (eg, fluoxetine) or TCAs (eg, clomipramine, imipramine). Accumulation of parent drug and/or failure of metabolite formation may decrease safety and/or efficacy of concomitant CYP2D6 substrates; adjust dose of CYP2D6 substrate or use alternative treatment. Reduce initial dose of concomitant desipramine (max 40mg/day), paroxetine (max 35mg/day). Monitor digoxin; may need to reduce dose. Additive CNS effects with alcohol.
Nuedexta Adverse Reactions
Diarrhea, dizziness, cough, vomiting, asthenia, peripheral edema, UTI, influenza, increased gamma-glutamyltransferase, flatulence; thrombocytopenia, hypersensitivity, anticholinergic effects, hepatitis (discontinue if occurs).
Nuedexta Clinical Trials
Nuedexta Patient Counseling