My mother is suffering from dry cough from almost 10 years. doctors says it is an ellergy. plz help her. her age is 50 years.?

Cough: Differential diagnosis would include, allergy, also asthma variant cough could present as dry cough. If a patient is on certain meds like vasotec (enalapril) ( belongs to class of meds known as ace inhibitors ) it can cause dry cough in 8-10% patients. Acid reflux is other common reason. Some of the test which may help are : allergy panel blood test, pulmonary function test, ct chest, see pulmonary md &ent md.