Our immune system is supposed to fight germs, but in some people, it gets triggered by harmless substances in the air (pollen, molds, microscopic particles from animals, cockroaches, dust mites). Maybe 20% of people have allergies, which can be mild or severe, come-and-go or be permanent. There are many types of Allergies; here we’re talking about Upper Respiratory Allergies (“Rhinitis” means inflammation of the nose (“rhino-“, like in “rhinoceros”) (see Diagram — Upper Respiratory Tract).
Allergic Rhinitis symptoms are similar to the Common Cold: runny nose, or maybe just coughing, if mucus from the nose slides down the throat to the trachea (“post-nasal drip”). We think more of Allergies if there’s lots of sneezing, or watery eyes. We also think of Allergies instead of a Cold if symptoms last a long time, or keep coming back (a cold only lasts 2 weeks; adults only get one a few times a year, children more).
Most over-the-counter medications & home remedies are close to useless (although placebo does always help a bit). Even though this website is about diagnosis, click for Allergy Medicines that work best.
Oftentimes a chronic sore throat or chronic cough will be symptoms of Allergic Rhinitis. Among patients with cough lasting over a month, and a normal chest x-ray, 99% will have one of the following conditions: