Evaluation of Cough Medication Use Patterns in Ambulatory Care Settings in the United States: 2003-2018

Efficacy and safety of Tanreqing injection for cough caused by acute trachea-bronchitis disease: A systematic review and meta-analysis of randomized controlled trials

ETHNOPHARMACOLOGICAL RELEVANCE

Tanreqing injection (TRQI) is an intravenous herbal preparation derived from 5 types of traditional Chinese medicines including Scutellariae Radix, Lonicerae Japonicae Flos, Forsythiae Fructus, bear bile powder and goral horn, incorporating baicalin, chlorogenic acid, ursodeoxycholic acid, and goose deoxycholic acid and other compounds known for anti-inflammatory properties, is widely used in China to treat cough caused by acute trachea-bronchitis disease (ATB).

AIM OF THE STUDY

To investigate the clinical efficacy and safety of Tanreqing injection (TRQI) with and without Western medicine (WM) for cough caused by acute trachea-bronchitis (ATB).

MATERIALS AND METHODS

We systematically searched eight databases, including CENTRAL, Embase, PubMed, Science Direct, Wiley, China National Knowledge Infrastructure, Chinese Biomedical Literature Database and WanFang, from inception to August 2023 for randomized clinical trials (RCTs) on TRQI for cough caused by ATB. The critical outcomes of interest were time to symptom disappearance, including time for cough symptom to disappear and time to improve cough and sputum production. Important outcomes included symptom disappearance rate, adverse events (AEs) and lung function. We carried out random-effects meta-analysis using Review Manager 5.4 and assessed the certainty of evidence utilizing the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

A total of 2872 citations were identified by our search, of which 26 eligible RCTs enrolled 2731 participants. Low to moderate certainty evidence showed that when compared with WM, TRQI plus WM treatment was associated with a favorable effect on the time for cough symptom to disappear (MD -2.21 d, 95% CI -2.64 to -1.78), time to improve cough and sputum production (MD -0.68 d, 95% CI -0.83 to -0.53), symptom disappearance rate (RR 1.37, 95% CI 1.20 to 1.55), forced vital capacity, and forced expiratory volume in 1 s (MD 0.38 L, 95% CI 0.26 to 0.50; MD 2.92%, 95% CI 1.29 to 4.56, respectively). In terms of AEs, there was no association between TRQI plus WM and WM (RR 0.55, 95% CI 0.14 to 2.21; low-certainty evidence). Very low certainty evidence showed that TRQI alone was associated with reduced time to improve cough and sputum (MD -0.14 d, 95% CI -0.26 to -0.02) and increased symptom disappearance rate (RR 1.89, 95% CI 1.24 to 2.88; low certainty evidence) compared to WM.

CONCLUSIONS

The overall efficacy of TRQI or WM for ATB cough is better than that of WM, and TRQI also effectively improve symptoms in patients with similar adverse events. However, due to the lack of methodological rigor of included studies, the present findings should be interpreted with caution. We advocate better high-quality and convincing clinical studies to be performed to prove the effectiveness and safety of TRQIs.

Benzonatate Safety and Effectiveness: A Systematic Review of the Literature

OBJECTIVE

To review the available literature regarding the treatment effects and efficacy of benzonatate needed to better inform patients, providers, and regulators evaluating its role in modern medical therapies.

DATA SOURCES

Comprehensive literature searches were conducted in PubMed, Embase (Elsevier), Cochrane Library, and Scopus for original research articles evaluating the effectiveness, tolerability, and safety profile of benzonatate from January 1956 through August 2022.

STUDY SELECTION AND DATA EXTRACTION

The identified studies were screened for relevance and then assessed for inclusion through a full-text review, data extraction, and quality assessment by multiple reviewers using the online software Covidence.

DATA SYNTHESIS

The selection process resulted in 37 articles consisting of 21 cohort studies, 5 experimental studies, and 11 case studies and series. Initial clinical studies exploring potential therapeutic benefits collected data from very small populations and limited clinical settings. Safety is primarily assessed in terms of toxicity due to overdose or inappropriate use. Quality assessment raised concerns for high degrees of biases primarily related to the limited sample size, data collection, generalizability, and study design.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This review reveals substantial limitations within existing evidence pertaining to the safety and clinical effectiveness of benzonatate and thus, a need for large observational studies or randomized trials to better characterize its role and value in modern medical practice.

CONCLUSIONS

Rising safety concerns should bring closer scrutiny upon the prescription of benzonatate whose approval is founded upon evidence that would not stand up to current regulatory review.

Patterns of Cough Medication Prescribing among Patients with Chronic Cough in Florida: 2012-2021

Among patients with chronic cough (CC) in the 2012-2021 statewide OneFlorida Clinical Research Consortium database, we examined trends in cough medication (CM) prescribing prevalence over time in repeated cross-sectional analyses and identified distinct CM utilization trajectories using group-based trajectory modeling (GBTM) in a retrospective cohort study. Among eligible adults (≥18 years) without cancer/benign respiratory tumor diagnoses, we identified CC patients and non-CC patients with any cough-related diagnosis. In the GBTM analysis, we calculated the number of monthly prescriptions for any CMs (excluding gabapentinoids) during the 12 months from the first qualifying cough event to identify distinct utilization trajectories. From 2012 to 2021, benzonatate (9.6% to 26.1%), dextromethorphan (5.2% to 8.6%), and gabapentinoid (5.3% to 14.4%) use increased among CC patients, while opioid antitussive use increased from 2012 to 2015 and decreased thereafter (8.4% in 2012, 14.7% in 2015, 6.7% in 2021; all p < 0.001). Of 15,566 CC patients and 655,250 non-CC patients identified in the GBTM analysis, CC patients had substantial burdens of respiratory/non-respiratory comorbidities and healthcare service and concomitant medication use compared to non-CC patients. Among CC patients, GBTM identified three distinct CM utilization trajectories: (1) no CM use (n = 11,222; 72.1%); (2) declining CM use (n = 4105; 26.4%); and (3) chronic CM use (n = 239; 1.5%). CC patients in Florida had limited CM use with increasing trends in use of benzonatate, dextromethorphan, and gabapentinoids and a decreasing trend in opioid antitussive use. CC patients, particularly with chronic prescription CM use, experienced substantial disease burden.

Benzonatate Exposure Trends and Adverse Events

BACKGROUND AND OBJECTIVES

Adverse events (AE), including death, occur in children with benzonatate use. This study aims to understand recent trends in benzonatate exposure and clinical consequences in pediatric patients.

METHODS

This retrospective analysis of data from IQVIA pharmacy drug dispensing, National Poison Data System, National Electronic Injury Surveillance System-Cooperative Adverse Drug Event Surveillance Project, FDA Adverse Event Reporting System, and the medical literature evaluated exposure trends and medication-related AEs with benzonatate. Trends for comparator narcotic and nonnarcotic antitussive medications were analyzed where possible for context.

RESULTS

During the study period, pediatric benzonatate prescription utilization increased but remained low compared with pediatric utilization of dextromethorphan-containing prescription antitussive medications. Among the 4689 pediatric benzonatate exposure cases reported to US poison control centers from 2010 to 2018, 3727 cases (80%) were for single-substance exposures. Of these, 3590 cases (77%) were unintentional exposures and most involved children 0 to 5 years old (2718 cases, 83%). Cases involving intentional benzonatate exposure increased among children 10 to 16 years old with a more pronounced increase for multiple-substance exposures. Most benzonatate cases involving misuse or abuse were for children 10 to 16 years old (59 cases, 61%). The proportion of cases with serious adverse effects was low. There were few cases annually of serious AEs with benzonatate in children.

CONCLUSIONS

There were rising patterns of unintentional ingestion of benzonatate in children 0 to 5 years old and intentional benzonatate ingestion in children 10 to 16 years old. Rational prescribing and improved provider and caregiver awareness of benzonatate toxic effects may reduce risks associated with benzonatate exposure.