Published online by Cambridge University Press: 07 November 2014
Patients with involuntary emotional expression disorder (IEED) have impaired social and occupational functioning and there is currently no Food and Drug Administration-approved treatment. Treatment options include tricyclic antidepressants (TCAs), selective serotonin reuptake inhibitors (SSRIs), dopaminergic agents, and a combination of dextromethorphan and quinidine. Studies of monaminergic agents have typically been small and executed in single-center settings. Assessment measures generally show significant symptomatic improvements, including a reduction in the number of laughing or crying episodes and improvements in patients' clinical condition. The tolerability profiles of these agents are well defined, and include dizziness, tachycardia, and QTc prolongation (TCAs), and sleep and sexual disturbances (SSRIs). The combination of dextromethorphan and quinidine has also been assessed in two large multicenter studies in patients with amyotrophic lateral sclerosis and multiple sclerosis. Compared with placebo and either agent alone, there were significant improvements in symptoms, quality of life, and relationships. The most common side effects were dizziness and nausea, and potential drug interactions with quinidine should also be considered. Choice of treatment should be evidence-based, taking into account both efficacy and tolerability.