Final answer:
The most frequent causes of chronic cough in nonsmokers without pulmonary disease are postnasal drip syndrome, GERD, and asthma, which typically prompt further investigation and targeted treatments.
Step-by-step explanation:
The most frequent causes of chronic cough in nonsmokers without underlying pulmonary disease are typically attributed to postnasal drip syndrome (also known as upper airway cough syndrome), gastroesophageal reflux disease (GERD), and asthma. These conditions are often considered when a patient presents with a chronic cough and has neither a history of smoking nor evidence of pulmonary disease.
Postnasal drip syndrome is a condition where excess mucus from the nose and sinuses drips down the back of the throat, leading to coughing as an attempt to clear the mucus. Gastroesophageal reflux disease (GERD) can cause stomach acids to flow back into the esophagus, leading to irritation and a chronic cough. Lastly, asthma, even in its less obvious forms, can present with a chronic cough as a primary symptom.
It's important to identify the underlying cause of a chronic cough in order to provide adequate treatment. For example, antihistamines and decongestants may alleviate symptoms caused by postnasal drip, proton pump inhibitors might be prescribed for GERD, and inhalers can be used for asthma management.