This study will examine how dextromethorphan, a drug that alters reflexes of the larynx (voice box), might change voice symptoms in people with voice disorders due to uncontrolled laryngeal muscle spasms. These include abductor spasmodic dysphonia (breathy voice breaks), adductor spasmodic dysphonia (vowel breaks), muscular tension dysphonia (tight strained voice), and vocal tremor (tremulous voice). Dextromethorphan-one of a group of drugs called NMDA antagonists-has been used for years in over-the-counter cough suppressant medicines. In animal studies, the drug has blocked one of the reflexes in the larynx that may be associated with spasms in the laryngeal muscles. This study will compare the effects of dextromethorphan, lorazepam (a valium-type drug), and a placebo (inactive substance) in patients with the four types of voice disorders described above. Patients with spasmodic dysphonia, muscular tension dysphonia and vocal tremor may be eligible for this study. Individuals who smoke or use tobacco, who have vocal nodules or polyps, or who have a history of airway obstruction may not participate. Candidates will be screened with a medical history and physical examination, a questionnaire, voice recording (repeating sentences into a microphone), and nasolaryngoscopy (examination of the larynx with a tube advanced through the nose). For the nasolaryngoscopy, the inside of the nose is sprayed with a decongestant (to open the nasal passages) and possibly a local anesthetic. A small, flexible tube called a nasolaryngoscope is passed through the nose to look at the larynx during speech and other tasks, such as singing, whistling and prolonged vowels. Participants will be admitted to the NIH Clinical Center for each of three visits, which will last from the afternoon of one day to late afternoon of the following day. At each visit, patients will complete a questionnaire, baseline speech recording, and a test for sedation level. They will take three pills-either dextromethorphan, lorazepam, or placebo-one every 6 hours. Vital signs will be checked every 6 hours and the level of sedation during waking hours will be monitored. One to three hours after taking the third pill, speech recording, questionnaire and test of sedation will be repeated to check for possible voice changes. Patients will be given a different pill at each visit. ...
Age range
18 Years – 80 Years
Sex
ALL
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