EC Pulmonology and Respiratory Medicine

Lung diseases are a significant health burden globally caused by unending exposure of the respiratory system to environmental pollutants, pathogens and other dangerous chemicals. Standard treatments of chronic and progressive lung diseases like asthma, chronic obstructive pulmonary disease (COPD), pulmonary fibrosis, lung cancer, and infectious pulmonary diseases have little success in managing disease progression or in treating these conditions. In this regard, small-molecule therapeutics came to be an important platform of contemporary lung care because of their low molecular weight, strong cellular penetration, and the capability to be administered orally, and low costs of production.

This literature review critically discusses the role of small molecules in the treatment of lung therapy by emphasising their properties, action, therapeutic uses, benefits, and limitations. The major areas of disease, including inflammatory diseases of the lung, fibrotic diseases, malignancies, and respiratory infection, are discussed as key areas of enzyme inhibition and receptor modulation. Bronchodilators, phosphodiesterase inhibitors, tyrosine kinase inhibitors, antifibrotic agents, and antiviral drugs are clinically relevant agents that come into the limelight of the review. Although they have these advantages, some issues persist, including resistance to drugs, off-target toxicity and limitations on delivery. Prior development of artificial intelligence used to discover new drugs, drug delivery systems using nanotechnology, and combination therapy with biologics has a positive future direction. The development of small-molecule therapeutics remains central in the history of the lung as a medicine, and future developments in the product are leading to more customised and targeted respiratory therapy.

 Keywords: Small Molecule Therapeutics; Lung Medicine; Pulmonary Diseases; Drug Discovery; Enzyme Inhibition; Receptor Modulation; Targeted Therapy; Respiratory Pharmacology

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