Indian Long Pepper (Piper longum) has a longstanding history of use in traditional Ayurvedic and Unani medicine for the treatment of respiratory conditions, including lung congestion. The fruit is considered an important component in classical formulations such as Trikatu (a blend of black pepper, long pepper, and ginger) that are used to manage cough, asthma, bronchitis, and other pulmonary disorders. According to traditional texts, Indian Long Pepper is believed to possess expectorant and bronchodilatory properties, which help clear mucus from the respiratory tract and alleviate congestion.

The evidence supporting these uses is mainly based on centuries of empirical practice and descriptions in traditional medical literature. Some preclinical studies have reported that extracts of Piper longum exhibit anti-inflammatory, immunomodulatory, and mild bronchodilatory effects in laboratory models, which could theoretically contribute to reducing lung congestion. However, robust clinical trials in humans are lacking, and the body of scientific evidence remains insufficient to fully validate these effects.

In summary, Indian Long Pepper is primarily justified for use in lung congestion by traditional medical systems, with some preliminary pharmacological data suggesting potential mechanisms. Nonetheless, high-quality clinical evidence is limited, so the use is best regarded as tradition-based.