Dextromethorphan to Treat Patients with Voice Spasms http://www.clinicaltrials.gov/ct/show/NCT00055549
A clinical study comparing the effects of dextromethorphan, lorazepam, and a placebo of dextromethorphan in individuals with spasmodic dysphonia, muscular tension dysphonia, or vocal tremor. Background and participation details are offered by the National Library of Medicine's ClinicalTrials.gov site.
National Spasmodic Dysphonia Association http://www.dystonia-foundation.org/nsda/
Resources for patients and professionals, including multimedia demonstrations of SD, descriptions of available therapies, information on a financial-assistance program for patients who require Botox, and listings for dystonia specialists, support groups, and upcoming events.