Safety and efficacy of Piper longum L. for acute respiratory infections: A systematic review

Abstract

Introduction

Antimicrobial resistance (AMR) is a serious threat to global public health by compromising the effectiveness of infection prevention and treatment strategies. This escalating issue necessitates the exploration of alternative treatments and natural remedies to reduce reliance on antibiotics. Piper longum L. has historically been used in the treatment of respiratory infections in Ayurvedic medicine. This systematic review aims to evaluate the safety and efficacy of Piper longum in managing Acute Respiratory Infections (ARIs).

Methods

Nine databases (PubMed, Embase, Cochrane CENTRAL, CINAHL, AMED, ProQuest, CNKI, and Google Scholar) were systematically searched for randomized controlled trials (RCTs) and non-randomized controlled clinical trials (NRCTs) evaluating Piper longum. The primary outcomes assessed were improvement in acute respiratory infections, ARI symptoms and side effects. A narrative approach was used to synthesize the data. The Cochrane Risk of Bias tool was used to assess study quality, and Rayyan was used to screen eligible studies. Data extraction was performed independently by two reviewers.

Results

Two studies met the inclusion criteria (one RCT and one NRCT). One study reported that Piper longum improved symptoms of acute respiratory infections (ARIs), including frequency of cough bouts, sleep disturbances, sputum production, crepitations, throat infections, wheezing, nasal discharge, and loss of appetite. Side effects associated with Piper longum ranged from minimal (such as chest burning) to none. However, the methodological quality of the included trials was generally poor.

Conclusion

Piper longum may be beneficial and safe for relieving symptoms of ARIs. Nevertheless, these findings should be interpreted with caution due to the poor methodological quality and heterogeneity of the included studies. To better understand the efficacy and safety of Piper longum, well-designed trials with rigorous methodologies and transparent reporting are necessary.