Researchers have found how environmental irritants, such as air pollution and cigarette smoke, trigger coughing.
In a study conducted by experts from Imperial College London and the University of Hull, it was found that irritants activate receptor proteins called TRPA1 on the surface of nerve endings in the lungs.
Subsequently, sensory nerves trigger a cough reflex.
The researchers insisted that blocking TRPA1 receptors could treat coughing.
Professor Maria Belvisi, co-author of the study from the National Heart and Lung Institute at Imperial College London, said: "For some people, chronic coughing can be annoying and uncomfortable, but for others it can be distressing and can have a severe impact on their quality of life.
"Many people say that certain things in the air can make them cough and we are very excited that we have shown, for the first time, exactly what is probably happening inside the lungs."
The researchers observed the sensory nerves from mice and guinea pigs as part of the study.
They also noted a number of irritants, including a key compound in cigarette smoke (acrolein) and a chemical called cinnamaldehyde.
But when they blocked the receptors, the substances no longer activated the nerves.
Maria concluded: "Now that we think we have cracked the mechanism, we can start investigating whether we can stop people from coughing excessively by blocking the receptor protein that triggers it."
The study was published in the American Journal of Respiratory and Critical Care Medicine.