What is the differential diagnosis of a chronic dry cough?

Gastroesophageal Reflux Disease (GERD): This is a common cause of chronic dry cough, especially if the cough is worse at night or after eating. The stomach acid can irritate the throat and lungs, leading to a persistent cough.

Asthma: A chronic respiratory condition that can cause dry cough, especially at night or with exercise. The cough may be accompanied by wheezing or shortness of breath.
Chronic Obstructive Pulmonary Disease (COPD): A progressive lung disease that can cause a chronic dry cough, often accompanied by shortness of breath and wheezing.
Allergic Rhinitis: An allergic reaction to airborne particles such as pollen, dust, or mold, which can cause a dry cough, sneezing, and runny nose.
Postnasal Drip: Mucus from the nose can drip down the back of the throat, causing a dry cough, especially at night.

Lung Cancer: Although less common, lung cancer can cause a chronic dry cough, especially if it is accompanied by weight loss, fatigue, or coughing up blood.
Tuberculosis (TB): A bacterial infection that can cause a chronic dry cough, often accompanied by fever, night sweats, and weight loss.
Pneumonia: A bacterial or viral infection that can cause a dry cough, especially if it is accompanied by fever, chills, and shortness of breath.
Pulmonary Embolism: A blood clot in the lungs that can cause a sudden onset of dry cough, often accompanied by chest pain and shortness of breath.

Sarcoidosis: A rare autoimmune disease that can cause a dry cough, often accompanied by fatigue, weight loss, and skin rashes.
Interstitial Lung Disease: A group of rare lung diseases that can cause a dry cough, often accompanied by shortness of breath and fatigue.
Eosinophilic Pneumonia: A rare lung disease caused by an allergic reaction, which can cause a dry cough, often accompanied by fever and shortness of breath.
Cystic Fibrosis: A rare genetic disorder that can cause a dry cough, often accompanied by recurrent lung infections and malnutrition.