Objective: To summarize the efficacy and safety data for use of nebulized lidocaine in intractable cough and asthma.
Data sources: A literature search was conducted using PubMed (through November 2012), International Pharmaceutical Abstracts (1970-December 2012), and Cochrane Library (up to 2012) with the search terms nebulization, nebulized or nebulised; administration, inhalation; cough; asthma; and lidocaine. Results were limited to human studies published in the English language. Referenced citations from relevant publications were also reviewed.
Study selection and data extraction: All articles identified from the data sources were reviewed for inclusion. Clinical trials and descriptive studies that discussed use of nebulized lidocaine for treatment of intractable cough and asthma were included in the review.
Data synthesis: Seventeen studies were identified for review. Seven studies (6 descriptive studies and 1 clinical trial) evaluating the use of nebulized lidocaine in intractable cough reported efficacy in doses ranging from 10 mg to 400 mg. Five clinical trials in asthma showed conflicting results regarding improvement in pulmonary function and glucocorticoid-sparing effects. General improvements in pulmonary function as well as the initial bronchoconstriction induced by nebulized lidocaine in subjects with baseline bronchial hyperreactivity were investigated in 5 studies. Overall, the available evidence does not appear to preclude the use of lidocaine as a treatment option for intractable cough after failure of traditional cough suppressants. Data on its use for short-term glucocorticoid-sparing effects in asthma are conflicting. Study limitations, including design, small sample size, and inconsistencies in method and adjunctive therapies, should be considered. Nebulized lidocaine is well tolerated; however, reports of initial bronchoconstriction have occurred.
Conclusions: Although nebulized lidocaine is not first-line therapy in intractable cough and asthma, it may provide an alternative treatment option in patients who cannot tolerate or are unresponsive to other treatments. Appropriate monitoring precautions should be used to ensure patient safety.