Comparative Pharmacology
Head-to-head clinical analysis: AUVELITY versus SYMBYAX.
Peer-Reviewed Evidence
Head-to-head clinical analysis: AUVELITY versus SYMBYAX.
AUVELITY vs SYMBYAX
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
AUVELITY (dextromethorphan HBr and bupropion HCl) is an NMDA receptor antagonist (via dextromethorphan) and a norepinephrine-dopamine reuptake inhibitor (via bupropion). Dextromethorphan also modulates sigma-1 receptor activity.
Symbyax is a combination of olanzapine (an atypical antipsychotic) and fluoxetine (a selective serotonin reuptake inhibitor). Olanzapine antagonizes dopamine D2, serotonin 5-HT2A, and other CNS receptors; fluoxetine inhibits serotonin reuptake. Synergy targets depressive and manic symptoms via dopaminergic and serotonergic modulation.
45 mg orally once daily, given as dextromethorphan hydrobromide 45 mg and bupropion hydrochloride 105 mg combination tablet.
6 mg/25 mg to 12 mg/50 mg orally once daily; maximum 12 mg/50 mg per day.
None Documented
None Documented
Dextromethorphan: 13.5 hours (terminal half-life; prolonged due to CYP2D6 inhibition by bupropion, allowing sustained NMDA antagonism; bupropion: 13.7 hours)
Olanzapine: 21-54 h (mean 30 h in adults; longer in elderly and hepatic impairment). Fluoxetine: 4-6 days (norfluoxetine 4-16 days). Extensive accumulation with chronic dosing; steady-state reached in 2-4 weeks for fluoxetine.
Renal 81% (dextromethorphan and metabolites: 78% as unchanged drug and 3% as dextrorphan conjugates), fecal 9% (dextromethorphan and metabolites), biliary <1%
Olanzapine: ~57% renal (7% unchanged, rest as metabolites; 30% fecal as metabolites from biliary excretion). Fluoxetine: ~60% renal (primarily as metabolites; <10% unchanged) and ~40% fecal (via biliary excretion of metabolites).
Category C
Category C
Antidepressant
Antidepressant/Antipsychotic Combination