Efficacy of Dextromethorphan plus Quinidine Demonstrated for Pseudobulbar Affect

Pseudobulbar affect (PBA), a severe outburst of emotional expression incongruous to a patient's emotional state, can occur in patients with amyotrophic lateral sclerosis (ALS), multiple sclerosis (MS), and several other neurological disorders. PBA occurs in 20% to 50% of patients with ALS and 5% to 10% of those with MS. In this phase III, 12-week, blinded, placebo-controlled, manufacturer-supported study, researchers randomized 326 patients with PBA and either ALS or MS to receive high-dose dextromethorphan/quinidine (30 mg/10 mg), lower-dose dextromethorphan/quinidine (20 mg/10 mg), or placebo twice daily. (Patients with significant electrocardiographic [ECG] abnormalities were excluded.) The primary outcome measure was the change from bas…