BACKGROUND: Pulmonary disease such as asthma is a psychosomatic disorder vulnerable to exacerbations precipitated by psychological factors. A case is described in which a patient thought to have treatment-refractory asthma was discovered to have a conversion reaction, specifically paradoxical vocal cord dysfunction (PVCD), characterized by abnormal vocal cord adduction during inspiration. DATA SOURCES: Reports of PVCD were located using a MEDLINE search and review of bibliographies. MEDLINE (English language only) was searched from 1966 through December 1998 using the terms functional asthma, functional upper airway obstruction, laryngeal diseases, Munchausen's stridor, paradoxical vocal cord dysfunction, psychogenic stridor, respiratory stridor, vocal cord dysfunction, and vocal cord paralysis. A total of 170 cases of PVCD were reviewed. STUDY FINDINGS: PVCD appears to be significantly more common among females. PVCD spans all age groups, including pediatric, adolescent, and adult patients. PVCD was most often misdiagnosed as asthma or upper airway disease. Because patients present with atypical and/or refractory symptoms, several diagnostic tests are employed to evaluate patients with PVCD; laryngoscopy is the most common. Direct visualization of abnormal vocal cord movement is the most definitive means of establishing the diagnosis of PVCD. A number of psychiatric disturbances are related to PVCD, including conversion and anxiety disorders. PVCD is associated with severe psychosocial stress and difficulties with modulation of intense emotional states. CONCLUSIONS: Psychogenic respiratory distress produced by PVCD can be easily misdiagnosed as severe or refractory asthma or other pulmonary disease states. Recognition of PVCD is important to avoid unnecessary medications and invasive treatments. Primary care physicians can detect cases of PVCD by attending to clinical symptoms, implementing appropriate laboratory investigations, and examining the psychological covariates of the disorder. Psychotherapy and speech therapy are effective in treating most cases of PVCD.