Allergic conditions are caused by an overactive immune system and are usually inherited. If your inheritance is mild you may only experience mild symptoms such as coughing. Family members with asthma, hayfever, atopic dermatitis, hives or drug allergies could suggest that you are susceptible to allergic conditions. This is important if you have persistent nasal dripping, itchy eyes, or lingering cough that remains unexplained. Search thoroughly for any family tendencies toward allergic conditions. Certain cigarette smokers can acquire these symptoms without allergic tendencies. Please see "Neck Cough: General Therapy" and "Neck Cough: Allergic Rhinitis and Hay Fever Therapy".