A stuffy nose that just won't go away is more likely to be allergies than a stubborn cold.

More than 54 percent of all Americans are allergic to dust mites, ragweed, rye, or other allergens, a recent study reports. Untreated allergies could increase your risk of asthma, eczema, or chronic sinusitis. If you have chronic nasal symptoms, see your healthcare provider for testing and advice.

In addition to increasing the risk of asthma, eczema, and chronic sinusitis, untreated allergies might also interfere with sleep, causing a sleep debt. Common allergens include detritus from dust mites and cockroaches, pollens from grass or trees, dander from cats or dogs, and spores from mold. The first step in treating allergies is limiting exposure to allergy triggers. Depending on a person's condition, allergies may be treated with over-the-counter antihistamines, nasal sprays, and eyedrops. If allergies are severe or do not respond to over-the-counter treatments, a healthcare provider may recommend prescription medication or other treatments, such as immunotherapy. Immunotherapy involves skin testing of common allergens and undergoing a series of injections, usually over several months or years, to reduce sensitivity to allergens.