Dextromethorphan

Novel (glutamate NMDA antagonist, serotonin reuptake inhibition)

  • Bipolar Depression4
  • Treatment resistant depression2
  • Pseudobulbar affect (as Neudexta with quinidine)
  • Agitation in dementia (as Neudexta with quinidine)2
  • Misuse potential but not controlled

Features

, , , ,
Handout

Dosing

Dextromethorphan 15-30 mg bid as monotherapy in bipolar depression, or augmented with bupropion 200-300 mg/day in unipolar

Can also use liquid OTC (dextromethorphan ER 30mg/5mL take 7.5ml bid) but prefer prescription tabs (less abuse potential).

Management

Works on own or as a quinidine-combination (Neudexta) for bipolar depression and TRD. Higher dose of dextramethorphan (30 mg bid) may also work. Quinidine prolongs the half-life of dextromethorphan, but should only be used in 10 mg dose (which is available in Neudexta or through compounding pharmacies).

EMR Text

Depression

Dextromethorphan use based on controlled trials in Major Depressive Disorder and FDA approval for this condition as a combination therapy with bupropion (Maji S et al, Psychiatry Res. 2024;342:116257).

Dextromethorphan side effects reviewed with patient.

Bipolar Depression

Dextromethorphan use based on controlled trials in bipolar depression (Chen SL et al, Eur Neuropsychopharmacol. 2014;24(11):1753-1759).

Dextromethorphan side effects reviewed with patient.

Agitation in Dementia

Dextromethorphan use based on controlled trials in agitation in dementia (Cummings JL et al, JAMA. 2015;314(12):1242-1254).

Dextromethorphan side effects reviewed with patient.

Search Treatments
Scroll to Top