2. Non-productive cough
Similar to how sneezing is triggered, cough is also common in patients why a respiratory allergy. But different than infections, allergic cough is often non-productive, which means that no sputum or secretion is produced, and when it is, chances are it will not be thick and green but transparent or white and more fluid. This is because, in some cases, allergies trigger production of mucus, but since it is not infected by anything else, it does not become purulent, greenish or foul-smelling.