A 2025 review undertook a comprehensive evaluation of the efficacy and safety of nebulized lidocaine for managing intractable cough in hospice care settings. The study encompassed a systematic literature search spanning from 1973 to 2023, examining 265 studies and selecting 58 that met rigorous inclusion criteria. The principal findings indicated that nebulized lidocaine, administered in concentrations of 1–4%, provided rapid cough suppression within 15 minutes in 70% of cancer patients, with effects lasting up to four hours. Reported side effects were generally mild and transient, such as oropharyngeal numbness and a bitter taste. However, bronchoconstriction was noted in 25% of asthmatic patients, necessitating bronchodilator intervention. Notably, lidocaine was effective in reducing opioid usage and enhancing patient comfort in 80% of cases. Despite its efficacy, variability in results was observed, particularly in patients with severe chronic obstructive pulmonary disease (COPD), suggesting limited benefits in those with acute respiratory failure. The narrative synthesis revealed differential responses in disease-specific contexts. For instance, while lidocaine was beneficial in mild-to-moderate asthma cases, it posed risks in severe cases due to potential bronchoconstriction. These findings underscore the critical need for personalized treatment approaches based on individual disease severity and patient phenotype. The review also highlighted methodological challenges, such as inconsistent dosing regimens and small sample sizes, impeding robust meta-analysis. Consequently, it advocates for future research focusing on standardized dosing, long-term safety evaluations, and the inclusion of randomized controlled trials to substantiate the therapeutic utility of nebulized lidocaine in diverse hospice populations. Additionally, the authors emphasize the importance of adopting preservative-free lidocaine formulations to mitigate airway irritation risks, particularly in sensitive patients. [1]
An older comprehensive review from 2013 synthesized efficacy and safety data concerning nebulized lidocaine use in intractable cough and asthma.This review incorporated 17 studies, comprising seven investigations on intractable cough, which revealed favorable outcomes at doses ranging from 10 mg to 400 mg. In contrast, the five clinical trials addressing asthma presented inconsistent results regarding the improvement of pulmonary functions and glucocorticoid-sparing effects. Specific attention was given to initial bronchoconstriction in subjects with baseline bronchial hyperreactivity, underscoring the need for cautious interpretation. The analysis, while acknowledging the potential therapeutic role of nebulized lidocaine, highlights significant study limitations, including small sample sizes and methodological inconsistencies. Despite the varied outcomes, nebulized lidocaine may serve as an alternative for patients with intractable cough unresponsive to conventional treatments. The tolerability profile is promising, though instances of bronchoconstriction warrant careful monitoring. The findings propose that while not a first-line therapy, nebulized lidocaine emerges as a viable option under certain clinical scenarios demanding individualized approaches. [2]
A 2023 meta-analysis aimed to assess the superiority of airway nerve blocks (ANBs) versus airway anesthesia without nerve blocks for awake tracheal intubation (ATI), including local anesthesia and local anesthetic nebulization. A total of 14 randomized controlled trials (RCTs) with 658 participants (ANBs group: 328 participants; No-ANBs group: 330) were included. Topical anesthesia included 2% atomized lidocaine, 2% nebulized lidocaine, 4% lidocaine by ultrasonic nebulizer, 4% lidocaine by jet nebulization, or lidocaine spray. The meta-analysis revealed that ANBs resulted in a reduced intubation time compared to no-ANBs (standardized mean difference [SMD] -2.57, 95% confidence interval [CI] −3.59 to −1.56; p <0.00001, I2 = 96%). The pooled analysis indicated that ANBs resulted in a greater absence of reaction to the placement of flexible score and tracheal tube compared to no-ANBs (77.18% versus 6.62%, relative risk [RR] 9.87; 95% CI 4.10 to 23.75, p <0.00001, I2 = 47%). The cough or gag reflex during intubation was also significantly lowered in the ANBs group than in the no-ANBs group (25.29% versus 72%, RR 0.35; 95% CI 0.27 to 0.46; p <0.00001; I2 = 17%). The satisfaction of patients was notably higher in the ANBs group compared to the no-ANBs group (68.22% versus 36.15%, RR 1.88; 95% CI 1.05 to 3.34; p = 0.03; I2 = 78%). Additionally, the overall complications was significantly lower in the ANBs group than in the no-ANBs group (15.50% versus 53.13%, RR 0.29; 95% CI 0.19 to 0.45; p <0.00001; I2 = 9%). The findings suggest that ANBs offer improved airway anesthesia quality for ATI, characterized by a shorter intubation time, enhanced intubation conditions with higher tolerance to the placement of the flexible score and tracheal tube, reduced cough or gag reflex during intubation, higher levels of excellent patient satisfaction, and a decrease in overall complication. [3]
A 2020 meta-analysis sought to identify differences in outcomes with or without nebulized lidocaine when used in bronchoscopy. Seven RCTs (N= 1,366) were included, with doses of nebulized lidocaine ranging from 60 mg to 300 mg (mean total dose 235 mg). Nebulized lidocaine, when compared to no nebulized lidocaine, did not amount to a difference in physician-reported cough score (SMD -0.09; 95% CI -0.7 to 0.51; I^2= 95%; p= 0.76). Subgroup analyses showed that in studies that only used local anesthesia, no nebulized lidocaine showed better cough scores (SMD 0.32; 95% CI 0.12 to 0.51; I^2= 77%; p= 0.001), however this difference was not statistically significant when moderate sedation was used. Additionally, for patient-reported cough scores no difference was seen between nebulized lidocaine and no nebulized lidocaine groups (SMD -0.12; 95% CI -0.82 to 0.59; I^2= 95%; p= 0.75). No differences were seen between groups for operator’s satisfaction score, ease or procedure, patient’s discomfort, and unwillingness to repeat the procedure. The additional nebulized lidocaine groups required higher doses of lidocaine in comparison to the no nebulization group (MD 86.9; 95% CI 34.83 to 138.96; I^2= 100%; p= 0.001). In a subgroup analysis of studies which used moderate sedation, the additional nebulized lidocaine group showed a decrease in midazolam dose and duration of procedure. Of note, this analysis is limited by differing scales used among studies to measure cough and significant heterogeneity between studies. Overall, the authors concluded that the additional administration of nebulized lidocaine did not have a significant effect on cough symptoms. [4]
A 2023 randomized, double-blind, double-dummy, placebo-controlled, 3-way crossover study was conducted to evaluate the efficacy of nebulized lidocaine versus lidocaine throat spray in patients with refractory chronic cough (RCC). This investigation involved 26 participants, predominantly female, with a mean age of 53.5 years. The study's primary outcome focused on cough frequency over a 10-hour period post-treatment, while secondary outcomes included visual analog scale scores for urge-to-cough and cough severity. An exploratory component also examined hourly cough rates up to 5 hours following treatment administration. The findings revealed that lidocaine throat spray significantly reduced cough frequency compared to placebo, with a notable impact within the first hour post-administration (31.7 coughs/h vs. 74.2 coughs/h; P = 0.004). Conversely, nebulized lidocaine did not exhibit a significant difference in cough frequency over the full 10-hour observation period. Both delivery methods, however, led to significant improvements in urge-to-cough and cough severity scores when compared with placebo (P <.05). No serious adverse events were linked to lidocaine use, indicating its safety profile. The results underline the potential of voltage-gated sodium channel inhibitors, specifically lidocaine throat spray, as promising therapeutic interventions for RCC, especially given their efficacy in reducing immediate cough frequency. [5]